/*
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
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/*
*
*
*
*
*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
*/
package java.util.concurrent;
import java.io.
ObjectStreamField;
import java.io.
Serializable;
import java.lang.reflect.
ParameterizedType;
import java.lang.reflect.
Type;
import java.util.
AbstractMap;
import java.util.
Arrays;
import java.util.
Collection;
import java.util.
Comparator;
import java.util.
Enumeration;
import java.util.
HashMap;
import java.util.
Hashtable;
import java.util.
Iterator;
import java.util.
Map;
import java.util.
NoSuchElementException;
import java.util.
Set;
import java.util.
Spliterator;
import java.util.concurrent.
ConcurrentMap;
import java.util.concurrent.
ForkJoinPool;
import java.util.concurrent.atomic.
AtomicReference;
import java.util.concurrent.locks.
LockSupport;
import java.util.concurrent.locks.
ReentrantLock;
import java.util.function.
BiConsumer;
import java.util.function.
BiFunction;
import java.util.function.
BinaryOperator;
import java.util.function.
Consumer;
import java.util.function.
DoubleBinaryOperator;
import java.util.function.
Function;
import java.util.function.
IntBinaryOperator;
import java.util.function.
LongBinaryOperator;
import java.util.function.
ToDoubleBiFunction;
import java.util.function.
ToDoubleFunction;
import java.util.function.
ToIntBiFunction;
import java.util.function.
ToIntFunction;
import java.util.function.
ToLongBiFunction;
import java.util.function.
ToLongFunction;
import java.util.stream.
Stream;
/**
* A hash table supporting full concurrency of retrievals and
* high expected concurrency for updates. This class obeys the
* same functional specification as {@link java.util.Hashtable}, and
* includes versions of methods corresponding to each method of
* {@code Hashtable}. However, even though all operations are
* thread-safe, retrieval operations do <em>not</em> entail locking,
* and there is <em>not</em> any support for locking the entire table
* in a way that prevents all access. This class is fully
* interoperable with {@code Hashtable} in programs that rely on its
* thread safety but not on its synchronization details.
*
* <p>Retrieval operations (including {@code get}) generally do not
* block, so may overlap with update operations (including {@code put}
* and {@code remove}). Retrievals reflect the results of the most
* recently <em>completed</em> update operations holding upon their
* onset. (More formally, an update operation for a given key bears a
* <em>happens-before</em> relation with any (non-null) retrieval for
* that key reporting the updated value.) For aggregate operations
* such as {@code putAll} and {@code clear}, concurrent retrievals may
* reflect insertion or removal of only some entries. Similarly,
* Iterators, Spliterators and Enumerations return elements reflecting the
* state of the hash table at some point at or since the creation of the
* iterator/enumeration. They do <em>not</em> throw {@link
* java.util.ConcurrentModificationException ConcurrentModificationException}.
* However, iterators are designed to be used by only one thread at a time.
* Bear in mind that the results of aggregate status methods including
* {@code size}, {@code isEmpty}, and {@code containsValue} are typically
* useful only when a map is not undergoing concurrent updates in other threads.
* Otherwise the results of these methods reflect transient states
* that may be adequate for monitoring or estimation purposes, but not
* for program control.
*
* <p>The table is dynamically expanded when there are too many
* collisions (i.e., keys that have distinct hash codes but fall into
* the same slot modulo the table size), with the expected average
* effect of maintaining roughly two bins per mapping (corresponding
* to a 0.75 load factor threshold for resizing). There may be much
* variance around this average as mappings are added and removed, but
* overall, this maintains a commonly accepted time/space tradeoff for
* hash tables. However, resizing this or any other kind of hash
* table may be a relatively slow operation. When possible, it is a
* good idea to provide a size estimate as an optional {@code
* initialCapacity} constructor argument. An additional optional
* {@code loadFactor} constructor argument provides a further means of
* customizing initial table capacity by specifying the table density
* to be used in calculating the amount of space to allocate for the
* given number of elements. Also, for compatibility with previous
* versions of this class, constructors may optionally specify an
* expected {@code concurrencyLevel} as an additional hint for
* internal sizing. Note that using many keys with exactly the same
* {@code hashCode()} is a sure way to slow down performance of any
* hash table. To ameliorate impact, when keys are {@link Comparable},
* this class may use comparison order among keys to help break ties.
*
* <p>A {@link Set} projection of a ConcurrentHashMap may be created
* (using {@link #newKeySet()} or {@link #newKeySet(int)}), or viewed
* (using {@link #keySet(Object)} when only keys are of interest, and the
* mapped values are (perhaps transiently) not used or all take the
* same mapping value.
*
* <p>A ConcurrentHashMap can be used as scalable frequency map (a
* form of histogram or multiset) by using {@link
* java.util.concurrent.atomic.LongAdder} values and initializing via
* {@link #computeIfAbsent computeIfAbsent}. For example, to add a count
* to a {@code ConcurrentHashMap<String,LongAdder> freqs}, you can use
* {@code freqs.computeIfAbsent(k -> new LongAdder()).increment();}
*
* <p>This class and its views and iterators implement all of the
* <em>optional</em> methods of the {@link Map} and {@link Iterator}
* interfaces.
*
* <p>Like {@link Hashtable} but unlike {@link HashMap}, this class
* does <em>not</em> allow {@code null} to be used as a key or value.
*
* <p>ConcurrentHashMaps support a set of sequential and parallel bulk
* operations that, unlike most {@link Stream} methods, are designed
* to be safely, and often sensibly, applied even with maps that are
* being concurrently updated by other threads; for example, when
* computing a snapshot summary of the values in a shared registry.
* There are three kinds of operation, each with four forms, accepting
* functions with Keys, Values, Entries, and (Key, Value) arguments
* and/or return values. Because the elements of a ConcurrentHashMap
* are not ordered in any particular way, and may be processed in
* different orders in different parallel executions, the correctness
* of supplied functions should not depend on any ordering, or on any
* other objects or values that may transiently change while
* computation is in progress; and except for forEach actions, should
* ideally be side-effect-free. Bulk operations on {@link java.util.Map.Entry}
* objects do not support method {@code setValue}.
*
* <ul>
* <li> forEach: Perform a given action on each element.
* A variant form applies a given transformation on each element
* before performing the action.</li>
*
* <li> search: Return the first available non-null result of
* applying a given function on each element; skipping further
* search when a result is found.</li>
*
* <li> reduce: Accumulate each element. The supplied reduction
* function cannot rely on ordering (more formally, it should be
* both associative and commutative). There are five variants:
*
* <ul>
*
* <li> Plain reductions. (There is not a form of this method for
* (key, value) function arguments since there is no corresponding
* return type.)</li>
*
* <li> Mapped reductions that accumulate the results of a given
* function applied to each element.</li>
*
* <li> Reductions to scalar doubles, longs, and ints, using a
* given basis value.</li>
*
* </ul>
* </li>
* </ul>
*
* <p>These bulk operations accept a {@code parallelismThreshold}
* argument. Methods proceed sequentially if the current map size is
* estimated to be less than the given threshold. Using a value of
* {@code Long.MAX_VALUE} suppresses all parallelism. Using a value
* of {@code 1} results in maximal parallelism by partitioning into
* enough subtasks to fully utilize the {@link
* ForkJoinPool#commonPool()} that is used for all parallel
* computations. Normally, you would initially choose one of these
* extreme values, and then measure performance of using in-between
* values that trade off overhead versus throughput.
*
* <p>The concurrency properties of bulk operations follow
* from those of ConcurrentHashMap: Any non-null result returned
* from {@code get(key)} and related access methods bears a
* happens-before relation with the associated insertion or
* update. The result of any bulk operation reflects the
* composition of these per-element relations (but is not
* necessarily atomic with respect to the map as a whole unless it
* is somehow known to be quiescent). Conversely, because keys
* and values in the map are never null, null serves as a reliable
* atomic indicator of the current lack of any result. To
* maintain this property, null serves as an implicit basis for
* all non-scalar reduction operations. For the double, long, and
* int versions, the basis should be one that, when combined with
* any other value, returns that other value (more formally, it
* should be the identity element for the reduction). Most common
* reductions have these properties; for example, computing a sum
* with basis 0 or a minimum with basis MAX_VALUE.
*
* <p>Search and transformation functions provided as arguments
* should similarly return null to indicate the lack of any result
* (in which case it is not used). In the case of mapped
* reductions, this also enables transformations to serve as
* filters, returning null (or, in the case of primitive
* specializations, the identity basis) if the element should not
* be combined. You can create compound transformations and
* filterings by composing them yourself under this "null means
* there is nothing there now" rule before using them in search or
* reduce operations.
*
* <p>Methods accepting and/or returning Entry arguments maintain
* key-value associations. They may be useful for example when
* finding the key for the greatest value. Note that "plain" Entry
* arguments can be supplied using {@code new
* AbstractMap.SimpleEntry(k,v)}.
*
* <p>Bulk operations may complete abruptly, throwing an
* exception encountered in the application of a supplied
* function. Bear in mind when handling such exceptions that other
* concurrently executing functions could also have thrown
* exceptions, or would have done so if the first exception had
* not occurred.
*
* <p>Speedups for parallel compared to sequential forms are common
* but not guaranteed. Parallel operations involving brief functions
* on small maps may execute more slowly than sequential forms if the
* underlying work to parallelize the computation is more expensive
* than the computation itself. Similarly, parallelization may not
* lead to much actual parallelism if all processors are busy
* performing unrelated tasks.
*
* <p>All arguments to all task methods must be non-null.
*
* <p>This class is a member of the
* <a href="{@docRoot}/../technotes/guides/collections/index.html">
* Java Collections Framework</a>.
*
* @since 1.5
* @author Doug Lea
* @param <K> the type of keys maintained by this map
* @param <V> the type of mapped values
*/
public class
ConcurrentHashMap<K,V> extends
AbstractMap<K,V>
implements
ConcurrentMap<K,V>,
Serializable {
private static final long
serialVersionUID = 7249069246763182397L;
/*
* Overview:
*
* The primary design goal of this hash table is to maintain
* concurrent readability (typically method get(), but also
* iterators and related methods) while minimizing update
* contention. Secondary goals are to keep space consumption about
* the same or better than java.util.HashMap, and to support high
* initial insertion rates on an empty table by many threads.
*
* This map usually acts as a binned (bucketed) hash table. Each
* key-value mapping is held in a Node. Most nodes are instances
* of the basic Node class with hash, key, value, and next
* fields. However, various subclasses exist: TreeNodes are
* arranged in balanced trees, not lists. TreeBins hold the roots
* of sets of TreeNodes. ForwardingNodes are placed at the heads
* of bins during resizing. ReservationNodes are used as
* placeholders while establishing values in computeIfAbsent and
* related methods. The types TreeBin, ForwardingNode, and
* ReservationNode do not hold normal user keys, values, or
* hashes, and are readily distinguishable during search etc
* because they have negative hash fields and null key and value
* fields. (These special nodes are either uncommon or transient,
* so the impact of carrying around some unused fields is
* insignificant.)
*
* The table is lazily initialized to a power-of-two size upon the
* first insertion. Each bin in the table normally contains a
* list of Nodes (most often, the list has only zero or one Node).
* Table accesses require volatile/atomic reads, writes, and
* CASes. Because there is no other way to arrange this without
* adding further indirections, we use intrinsics
* (sun.misc.Unsafe) operations.
*
* We use the top (sign) bit of Node hash fields for control
* purposes -- it is available anyway because of addressing
* constraints. Nodes with negative hash fields are specially
* handled or ignored in map methods.
*
* Insertion (via put or its variants) of the first node in an
* empty bin is performed by just CASing it to the bin. This is
* by far the most common case for put operations under most
* key/hash distributions. Other update operations (insert,
* delete, and replace) require locks. We do not want to waste
* the space required to associate a distinct lock object with
* each bin, so instead use the first node of a bin list itself as
* a lock. Locking support for these locks relies on builtin
* "synchronized" monitors.
*
* Using the first node of a list as a lock does not by itself
* suffice though: When a node is locked, any update must first
* validate that it is still the first node after locking it, and
* retry if not. Because new nodes are always appended to lists,
* once a node is first in a bin, it remains first until deleted
* or the bin becomes invalidated (upon resizing).
*
* The main disadvantage of per-bin locks is that other update
* operations on other nodes in a bin list protected by the same
* lock can stall, for example when user equals() or mapping
* functions take a long time. However, statistically, under
* random hash codes, this is not a common problem. Ideally, the
* frequency of nodes in bins follows a Poisson distribution
* (http://en.wikipedia.org/wiki/Poisson_distribution) with a
* parameter of about 0.5 on average, given the resizing threshold
* of 0.75, although with a large variance because of resizing
* granularity. Ignoring variance, the expected occurrences of
* list size k are (exp(-0.5) * pow(0.5, k) / factorial(k)). The
* first values are:
*
* 0: 0.60653066
* 1: 0.30326533
* 2: 0.07581633
* 3: 0.01263606
* 4: 0.00157952
* 5: 0.00015795
* 6: 0.00001316
* 7: 0.00000094
* 8: 0.00000006
* more: less than 1 in ten million
*
* Lock contention probability for two threads accessing distinct
* elements is roughly 1 / (8 * #elements) under random hashes.
*
* Actual hash code distributions encountered in practice
* sometimes deviate significantly from uniform randomness. This
* includes the case when N > (1<<30), so some keys MUST collide.
* Similarly for dumb or hostile usages in which multiple keys are
* designed to have identical hash codes or ones that differs only
* in masked-out high bits. So we use a secondary strategy that
* applies when the number of nodes in a bin exceeds a
* threshold. These TreeBins use a balanced tree to hold nodes (a
* specialized form of red-black trees), bounding search time to
* O(log N). Each search step in a TreeBin is at least twice as
* slow as in a regular list, but given that N cannot exceed
* (1<<64) (before running out of addresses) this bounds search
* steps, lock hold times, etc, to reasonable constants (roughly
* 100 nodes inspected per operation worst case) so long as keys
* are Comparable (which is very common -- String, Long, etc).
* TreeBin nodes (TreeNodes) also maintain the same "next"
* traversal pointers as regular nodes, so can be traversed in
* iterators in the same way.
*
* The table is resized when occupancy exceeds a percentage
* threshold (nominally, 0.75, but see below). Any thread
* noticing an overfull bin may assist in resizing after the
* initiating thread allocates and sets up the replacement array.
* However, rather than stalling, these other threads may proceed
* with insertions etc. The use of TreeBins shields us from the
* worst case effects of overfilling while resizes are in
* progress. Resizing proceeds by transferring bins, one by one,
* from the table to the next table. However, threads claim small
* blocks of indices to transfer (via field transferIndex) before
* doing so, reducing contention. A generation stamp in field
* sizeCtl ensures that resizings do not overlap. Because we are
* using power-of-two expansion, the elements from each bin must
* either stay at same index, or move with a power of two
* offset. We eliminate unnecessary node creation by catching
* cases where old nodes can be reused because their next fields
* won't change. On average, only about one-sixth of them need
* cloning when a table doubles. The nodes they replace will be
* garbage collectable as soon as they are no longer referenced by
* any reader thread that may be in the midst of concurrently
* traversing table. Upon transfer, the old table bin contains
* only a special forwarding node (with hash field "MOVED") that
* contains the next table as its key. On encountering a
* forwarding node, access and update operations restart, using
* the new table.
*
* Each bin transfer requires its bin lock, which can stall
* waiting for locks while resizing. However, because other
* threads can join in and help resize rather than contend for
* locks, average aggregate waits become shorter as resizing
* progresses. The transfer operation must also ensure that all
* accessible bins in both the old and new table are usable by any
* traversal. This is arranged in part by proceeding from the
* last bin (table.length - 1) up towards the first. Upon seeing
* a forwarding node, traversals (see class Traverser) arrange to
* move to the new table without revisiting nodes. To ensure that
* no intervening nodes are skipped even when moved out of order,
* a stack (see class TableStack) is created on first encounter of
* a forwarding node during a traversal, to maintain its place if
* later processing the current table. The need for these
* save/restore mechanics is relatively rare, but when one
* forwarding node is encountered, typically many more will be.
* So Traversers use a simple caching scheme to avoid creating so
* many new TableStack nodes. (Thanks to Peter Levart for
* suggesting use of a stack here.)
*
* The traversal scheme also applies to partial traversals of
* ranges of bins (via an alternate Traverser constructor)
* to support partitioned aggregate operations. Also, read-only
* operations give up if ever forwarded to a null table, which
* provides support for shutdown-style clearing, which is also not
* currently implemented.
*
* Lazy table initialization minimizes footprint until first use,
* and also avoids resizings when the first operation is from a
* putAll, constructor with map argument, or deserialization.
* These cases attempt to override the initial capacity settings,
* but harmlessly fail to take effect in cases of races.
*
* The element count is maintained using a specialization of
* LongAdder. We need to incorporate a specialization rather than
* just use a LongAdder in order to access implicit
* contention-sensing that leads to creation of multiple
* CounterCells. The counter mechanics avoid contention on
* updates but can encounter cache thrashing if read too
* frequently during concurrent access. To avoid reading so often,
* resizing under contention is attempted only upon adding to a
* bin already holding two or more nodes. Under uniform hash
* distributions, the probability of this occurring at threshold
* is around 13%, meaning that only about 1 in 8 puts check
* threshold (and after resizing, many fewer do so).
*
* TreeBins use a special form of comparison for search and
* related operations (which is the main reason we cannot use
* existing collections such as TreeMaps). TreeBins contain
* Comparable elements, but may contain others, as well as
* elements that are Comparable but not necessarily Comparable for
* the same T, so we cannot invoke compareTo among them. To handle
* this, the tree is ordered primarily by hash value, then by
* Comparable.compareTo order if applicable. On lookup at a node,
* if elements are not comparable or compare as 0 then both left
* and right children may need to be searched in the case of tied
* hash values. (This corresponds to the full list search that
* would be necessary if all elements were non-Comparable and had
* tied hashes.) On insertion, to keep a total ordering (or as
* close as is required here) across rebalancings, we compare
* classes and identityHashCodes as tie-breakers. The red-black
* balancing code is updated from pre-jdk-collections
* (http://gee.cs.oswego.edu/dl/classes/collections/RBCell.java)
* based in turn on Cormen, Leiserson, and Rivest "Introduction to
* Algorithms" (CLR).
*
* TreeBins also require an additional locking mechanism. While
* list traversal is always possible by readers even during
* updates, tree traversal is not, mainly because of tree-rotations
* that may change the root node and/or its linkages. TreeBins
* include a simple read-write lock mechanism parasitic on the
* main bin-synchronization strategy: Structural adjustments
* associated with an insertion or removal are already bin-locked
* (and so cannot conflict with other writers) but must wait for
* ongoing readers to finish. Since there can be only one such
* waiter, we use a simple scheme using a single "waiter" field to
* block writers. However, readers need never block. If the root
* lock is held, they proceed along the slow traversal path (via
* next-pointers) until the lock becomes available or the list is
* exhausted, whichever comes first. These cases are not fast, but
* maximize aggregate expected throughput.
*
* Maintaining API and serialization compatibility with previous
* versions of this class introduces several oddities. Mainly: We
* leave untouched but unused constructor arguments refering to
* concurrencyLevel. We accept a loadFactor constructor argument,
* but apply it only to initial table capacity (which is the only
* time that we can guarantee to honor it.) We also declare an
* unused "Segment" class that is instantiated in minimal form
* only when serializing.
*
* Also, solely for compatibility with previous versions of this
* class, it extends AbstractMap, even though all of its methods
* are overridden, so it is just useless baggage.
*
* This file is organized to make things a little easier to follow
* while reading than they might otherwise: First the main static
* declarations and utilities, then fields, then main public
* methods (with a few factorings of multiple public methods into
* internal ones), then sizing methods, trees, traversers, and
* bulk operations.
*/
/* ---------------- Constants -------------- */
/**
* The largest possible table capacity. This value must be
* exactly 1<<30 to stay within Java array allocation and indexing
* bounds for power of two table sizes, and is further required
* because the top two bits of 32bit hash fields are used for
* control purposes.
*/
private static final int
MAXIMUM_CAPACITY = 1 << 30;
/**
* The default initial table capacity. Must be a power of 2
* (i.e., at least 1) and at most MAXIMUM_CAPACITY.
*/
private static final int
DEFAULT_CAPACITY = 16;
/**
* The largest possible (non-power of two) array size.
* Needed by toArray and related methods.
*/
static final int
MAX_ARRAY_SIZE =
Integer.
MAX_VALUE - 8;
/**
* The default concurrency level for this table. Unused but
* defined for compatibility with previous versions of this class.
*/
private static final int
DEFAULT_CONCURRENCY_LEVEL = 16;
/**
* The load factor for this table. Overrides of this value in
* constructors affect only the initial table capacity. The
* actual floating point value isn't normally used -- it is
* simpler to use expressions such as {@code n - (n >>> 2)} for
* the associated resizing threshold.
*/
private static final float
LOAD_FACTOR = 0.75f;
/**
* The bin count threshold for using a tree rather than list for a
* bin. Bins are converted to trees when adding an element to a
* bin with at least this many nodes. The value must be greater
* than 2, and should be at least 8 to mesh with assumptions in
* tree removal about conversion back to plain bins upon
* shrinkage.
*/
static final int
TREEIFY_THRESHOLD = 8;
/**
* The bin count threshold for untreeifying a (split) bin during a
* resize operation. Should be less than TREEIFY_THRESHOLD, and at
* most 6 to mesh with shrinkage detection under removal.
*/
static final int
UNTREEIFY_THRESHOLD = 6;
/**
* The smallest table capacity for which bins may be treeified.
* (Otherwise the table is resized if too many nodes in a bin.)
* The value should be at least 4 * TREEIFY_THRESHOLD to avoid
* conflicts between resizing and treeification thresholds.
*/
static final int
MIN_TREEIFY_CAPACITY = 64;
/**
* Minimum number of rebinnings per transfer step. Ranges are
* subdivided to allow multiple resizer threads. This value
* serves as a lower bound to avoid resizers encountering
* excessive memory contention. The value should be at least
* DEFAULT_CAPACITY.
*/
private static final int
MIN_TRANSFER_STRIDE = 16;
/**
* The number of bits used for generation stamp in sizeCtl.
* Must be at least 6 for 32bit arrays.
*/
private static int
RESIZE_STAMP_BITS = 16;
/**
* The maximum number of threads that can help resize.
* Must fit in 32 - RESIZE_STAMP_BITS bits.
*/
private static final int
MAX_RESIZERS = (1 << (32 -
RESIZE_STAMP_BITS)) - 1;
/**
* The bit shift for recording size stamp in sizeCtl.
*/
private static final int
RESIZE_STAMP_SHIFT = 32 -
RESIZE_STAMP_BITS;
/*
* Encodings for Node hash fields. See above for explanation.
*/
static final int
MOVED = -1; // hash for forwarding nodes
static final int
TREEBIN = -2; // hash for roots of trees
static final int
RESERVED = -3; // hash for transient reservations
static final int
HASH_BITS = 0x7fffffff; // usable bits of normal node hash
/** Number of CPUS, to place bounds on some sizings */
static final int
NCPU =
Runtime.
getRuntime().
availableProcessors();
/** For serialization compatibility. */
private static final
ObjectStreamField[]
serialPersistentFields = {
new
ObjectStreamField("segments",
Segment[].class),
new
ObjectStreamField("segmentMask",
Integer.
TYPE),
new
ObjectStreamField("segmentShift",
Integer.
TYPE)
};
/* ---------------- Nodes -------------- */
/**
* Key-value entry. This class is never exported out as a
* user-mutable Map.Entry (i.e., one supporting setValue; see
* MapEntry below), but can be used for read-only traversals used
* in bulk tasks. Subclasses of Node with a negative hash field
* are special, and contain null keys and values (but are never
* exported). Otherwise, keys and vals are never null.
*/
static class
Node<K,V> implements
Map.
Entry<K,V> {
final int
hash;
final K
key;
volatile V
val;
volatile
Node<K,V>
next;
Node(int
hash, K
key, V
val,
Node<K,V>
next) {
this.
hash =
hash;
this.
key =
key;
this.
val =
val;
this.
next =
next;
}
public final K
getKey() { return
key; }
public final V
getValue() { return
val; }
public final int
hashCode() { return
key.
hashCode() ^
val.
hashCode(); }
public final
String toString(){ return
key + "=" +
val; }
public final V
setValue(V
value) {
throw new
UnsupportedOperationException();
}
public final boolean
equals(
Object o) {
Object k,
v,
u;
Map.
Entry<?,?>
e;
return ((
o instanceof
Map.
Entry) &&
(
k = (
e = (
Map.
Entry<?,?>)
o).
getKey()) != null &&
(
v =
e.
getValue()) != null &&
(
k ==
key ||
k.
equals(
key)) &&
(
v == (
u =
val) ||
v.
equals(
u)));
}
/**
* Virtualized support for map.get(); overridden in subclasses.
*/
Node<K,V>
find(int
h,
Object k) {
Node<K,V>
e = this;
if (
k != null) {
do {
K
ek;
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
k || (
ek != null &&
k.
equals(
ek))))
return
e;
} while ((
e =
e.
next) != null);
}
return null;
}
}
/* ---------------- Static utilities -------------- */
/**
* Spreads (XORs) higher bits of hash to lower and also forces top
* bit to 0. Because the table uses power-of-two masking, sets of
* hashes that vary only in bits above the current mask will
* always collide. (Among known examples are sets of Float keys
* holding consecutive whole numbers in small tables.) So we
* apply a transform that spreads the impact of higher bits
* downward. There is a tradeoff between speed, utility, and
* quality of bit-spreading. Because many common sets of hashes
* are already reasonably distributed (so don't benefit from
* spreading), and because we use trees to handle large sets of
* collisions in bins, we just XOR some shifted bits in the
* cheapest possible way to reduce systematic lossage, as well as
* to incorporate impact of the highest bits that would otherwise
* never be used in index calculations because of table bounds.
*/
static final int
spread(int
h) {
return (
h ^ (
h >>> 16)) &
HASH_BITS;
}
/**
* Returns a power of two table size for the given desired capacity.
* See Hackers Delight, sec 3.2
*/
private static final int
tableSizeFor(int
c) {
int
n =
c - 1;
n |=
n >>> 1;
n |=
n >>> 2;
n |=
n >>> 4;
n |=
n >>> 8;
n |=
n >>> 16;
return (
n < 0) ? 1 : (
n >=
MAXIMUM_CAPACITY) ?
MAXIMUM_CAPACITY :
n + 1;
}
/**
* Returns x's Class if it is of the form "class C implements
* Comparable<C>", else null.
*/
static
Class<?>
comparableClassFor(
Object x) {
if (
x instanceof
Comparable) {
Class<?>
c;
Type[]
ts,
as;
Type t;
ParameterizedType p;
if ((
c =
x.
getClass()) ==
String.class) // bypass checks
return
c;
if ((
ts =
c.
getGenericInterfaces()) != null) {
for (int
i = 0;
i <
ts.length; ++
i) {
if (((
t =
ts[
i]) instanceof
ParameterizedType) &&
((
p = (
ParameterizedType)
t).
getRawType() ==
Comparable.class) &&
(
as =
p.
getActualTypeArguments()) != null &&
as.length == 1 &&
as[0] ==
c) // type arg is c
return
c;
}
}
}
return null;
}
/**
* Returns k.compareTo(x) if x matches kc (k's screened comparable
* class), else 0.
*/
@
SuppressWarnings({"rawtypes","unchecked"}) // for cast to Comparable
static int
compareComparables(
Class<?>
kc,
Object k,
Object x) {
return (
x == null ||
x.
getClass() !=
kc ? 0 :
((
Comparable)
k).
compareTo(
x));
}
/* ---------------- Table element access -------------- */
/*
* Volatile access methods are used for table elements as well as
* elements of in-progress next table while resizing. All uses of
* the tab arguments must be null checked by callers. All callers
* also paranoically precheck that tab's length is not zero (or an
* equivalent check), thus ensuring that any index argument taking
* the form of a hash value anded with (length - 1) is a valid
* index. Note that, to be correct wrt arbitrary concurrency
* errors by users, these checks must operate on local variables,
* which accounts for some odd-looking inline assignments below.
* Note that calls to setTabAt always occur within locked regions,
* and so in principle require only release ordering, not
* full volatile semantics, but are currently coded as volatile
* writes to be conservative.
*/
@
SuppressWarnings("unchecked")
static final <K,V>
Node<K,V>
tabAt(
Node<K,V>[]
tab, int
i) {
return (
Node<K,V>)
U.
getObjectVolatile(
tab, ((long)
i <<
ASHIFT) +
ABASE);
}
static final <K,V> boolean
casTabAt(
Node<K,V>[]
tab, int
i,
Node<K,V>
c,
Node<K,V>
v) {
return
U.
compareAndSwapObject(
tab, ((long)
i <<
ASHIFT) +
ABASE,
c,
v);
}
static final <K,V> void
setTabAt(
Node<K,V>[]
tab, int
i,
Node<K,V>
v) {
U.
putObjectVolatile(
tab, ((long)
i <<
ASHIFT) +
ABASE,
v);
}
/* ---------------- Fields -------------- */
/**
* The array of bins. Lazily initialized upon first insertion.
* Size is always a power of two. Accessed directly by iterators.
*/
transient volatile
Node<K,V>[]
table;
/**
* The next table to use; non-null only while resizing.
*/
private transient volatile
Node<K,V>[]
nextTable;
/**
* Base counter value, used mainly when there is no contention,
* but also as a fallback during table initialization
* races. Updated via CAS.
*/
private transient volatile long
baseCount;
/**
* Table initialization and resizing control. When negative, the
* table is being initialized or resized: -1 for initialization,
* else -(1 + the number of active resizing threads). Otherwise,
* when table is null, holds the initial table size to use upon
* creation, or 0 for default. After initialization, holds the
* next element count value upon which to resize the table.
*/
private transient volatile int
sizeCtl;
/**
* The next table index (plus one) to split while resizing.
*/
private transient volatile int
transferIndex;
/**
* Spinlock (locked via CAS) used when resizing and/or creating CounterCells.
*/
private transient volatile int
cellsBusy;
/**
* Table of counter cells. When non-null, size is a power of 2.
*/
private transient volatile
CounterCell[]
counterCells;
// views
private transient
KeySetView<K,V>
keySet;
private transient
ValuesView<K,V>
values;
private transient
EntrySetView<K,V>
entrySet;
/* ---------------- Public operations -------------- */
/**
* Creates a new, empty map with the default initial table size (16).
*/
public
ConcurrentHashMap() {
}
/**
* Creates a new, empty map with an initial table size
* accommodating the specified number of elements without the need
* to dynamically resize.
*
* @param initialCapacity The implementation performs internal
* sizing to accommodate this many elements.
* @throws IllegalArgumentException if the initial capacity of
* elements is negative
*/
public
ConcurrentHashMap(int
initialCapacity) {
if (
initialCapacity < 0)
throw new
IllegalArgumentException();
int
cap = ((
initialCapacity >= (
MAXIMUM_CAPACITY >>> 1)) ?
MAXIMUM_CAPACITY :
tableSizeFor(
initialCapacity + (
initialCapacity >>> 1) + 1));
this.
sizeCtl =
cap;
}
/**
* Creates a new map with the same mappings as the given map.
*
* @param m the map
*/
public
ConcurrentHashMap(
Map<? extends K, ? extends V>
m) {
this.
sizeCtl =
DEFAULT_CAPACITY;
putAll(
m);
}
/**
* Creates a new, empty map with an initial table size based on
* the given number of elements ({@code initialCapacity}) and
* initial table density ({@code loadFactor}).
*
* @param initialCapacity the initial capacity. The implementation
* performs internal sizing to accommodate this many elements,
* given the specified load factor.
* @param loadFactor the load factor (table density) for
* establishing the initial table size
* @throws IllegalArgumentException if the initial capacity of
* elements is negative or the load factor is nonpositive
*
* @since 1.6
*/
public
ConcurrentHashMap(int
initialCapacity, float
loadFactor) {
this(
initialCapacity,
loadFactor, 1);
}
/**
* Creates a new, empty map with an initial table size based on
* the given number of elements ({@code initialCapacity}), table
* density ({@code loadFactor}), and number of concurrently
* updating threads ({@code concurrencyLevel}).
*
* @param initialCapacity the initial capacity. The implementation
* performs internal sizing to accommodate this many elements,
* given the specified load factor.
* @param loadFactor the load factor (table density) for
* establishing the initial table size
* @param concurrencyLevel the estimated number of concurrently
* updating threads. The implementation may use this value as
* a sizing hint.
* @throws IllegalArgumentException if the initial capacity is
* negative or the load factor or concurrencyLevel are
* nonpositive
*/
public
ConcurrentHashMap(int
initialCapacity,
float
loadFactor, int
concurrencyLevel) {
if (!(
loadFactor > 0.0f) ||
initialCapacity < 0 ||
concurrencyLevel <= 0)
throw new
IllegalArgumentException();
if (
initialCapacity <
concurrencyLevel) // Use at least as many bins
initialCapacity =
concurrencyLevel; // as estimated threads
long
size = (long)(1.0 + (long)
initialCapacity /
loadFactor);
int
cap = (
size >= (long)
MAXIMUM_CAPACITY) ?
MAXIMUM_CAPACITY :
tableSizeFor((int)
size);
this.
sizeCtl =
cap;
}
// Original (since JDK1.2) Map methods
/**
* {@inheritDoc}
*/
public int
size() {
long
n =
sumCount();
return ((
n < 0L) ? 0 :
(
n > (long)
Integer.
MAX_VALUE) ?
Integer.
MAX_VALUE :
(int)
n);
}
/**
* {@inheritDoc}
*/
public boolean
isEmpty() {
return
sumCount() <= 0L; // ignore transient negative values
}
/**
* Returns the value to which the specified key is mapped,
* or {@code null} if this map contains no mapping for the key.
*
* <p>More formally, if this map contains a mapping from a key
* {@code k} to a value {@code v} such that {@code key.equals(k)},
* then this method returns {@code v}; otherwise it returns
* {@code null}. (There can be at most one such mapping.)
*
* @throws NullPointerException if the specified key is null
*/
public V
get(
Object key) {
Node<K,V>[]
tab;
Node<K,V>
e,
p; int
n,
eh; K
ek;
int
h =
spread(
key.
hashCode());
if ((
tab =
table) != null && (
n =
tab.length) > 0 &&
(
e =
tabAt(
tab, (
n - 1) &
h)) != null) {
if ((
eh =
e.
hash) ==
h) {
if ((
ek =
e.
key) ==
key || (
ek != null &&
key.
equals(
ek)))
return
e.
val;
}
else if (
eh < 0)
return (
p =
e.
find(
h,
key)) != null ?
p.
val : null;
while ((
e =
e.
next) != null) {
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
key || (
ek != null &&
key.
equals(
ek))))
return
e.
val;
}
}
return null;
}
/**
* Tests if the specified object is a key in this table.
*
* @param key possible key
* @return {@code true} if and only if the specified object
* is a key in this table, as determined by the
* {@code equals} method; {@code false} otherwise
* @throws NullPointerException if the specified key is null
*/
public boolean
containsKey(
Object key) {
return
get(
key) != null;
}
/**
* Returns {@code true} if this map maps one or more keys to the
* specified value. Note: This method may require a full traversal
* of the map, and is much slower than method {@code containsKey}.
*
* @param value value whose presence in this map is to be tested
* @return {@code true} if this map maps one or more keys to the
* specified value
* @throws NullPointerException if the specified value is null
*/
public boolean
containsValue(
Object value) {
if (
value == null)
throw new
NullPointerException();
Node<K,V>[]
t;
if ((
t =
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; ) {
V
v;
if ((
v =
p.
val) ==
value || (
v != null &&
value.
equals(
v)))
return true;
}
}
return false;
}
/**
* Maps the specified key to the specified value in this table.
* Neither the key nor the value can be null.
*
* <p>The value can be retrieved by calling the {@code get} method
* with a key that is equal to the original key.
*
* @param key key with which the specified value is to be associated
* @param value value to be associated with the specified key
* @return the previous value associated with {@code key}, or
* {@code null} if there was no mapping for {@code key}
* @throws NullPointerException if the specified key or value is null
*/
public V
put(K
key, V
value) {
return
putVal(
key,
value, false);
}
/** Implementation for put and putIfAbsent */
final V
putVal(K
key, V
value, boolean
onlyIfAbsent) {
if (
key == null ||
value == null) throw new
NullPointerException();
int
hash =
spread(
key.
hashCode());
int
binCount = 0;
for (
Node<K,V>[]
tab =
table;;) {
Node<K,V>
f; int
n,
i,
fh;
if (
tab == null || (
n =
tab.length) == 0)
tab =
initTable();
else if ((
f =
tabAt(
tab,
i = (
n - 1) &
hash)) == null) {
if (
casTabAt(
tab,
i, null,
new
Node<K,V>(
hash,
key,
value, null)))
break; // no lock when adding to empty bin
}
else if ((
fh =
f.
hash) ==
MOVED)
tab =
helpTransfer(
tab,
f);
else {
V
oldVal = null;
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
if (
fh >= 0) {
binCount = 1;
for (
Node<K,V>
e =
f;; ++
binCount) {
K
ek;
if (
e.
hash ==
hash &&
((
ek =
e.
key) ==
key ||
(
ek != null &&
key.
equals(
ek)))) {
oldVal =
e.
val;
if (!
onlyIfAbsent)
e.
val =
value;
break;
}
Node<K,V>
pred =
e;
if ((
e =
e.
next) == null) {
pred.
next = new
Node<K,V>(
hash,
key,
value, null);
break;
}
}
}
else if (
f instanceof
TreeBin) {
Node<K,V>
p;
binCount = 2;
if ((
p = ((
TreeBin<K,V>)
f).
putTreeVal(
hash,
key,
value)) != null) {
oldVal =
p.
val;
if (!
onlyIfAbsent)
p.
val =
value;
}
}
}
}
if (
binCount != 0) {
if (
binCount >=
TREEIFY_THRESHOLD)
treeifyBin(
tab,
i);
if (
oldVal != null)
return
oldVal;
break;
}
}
}
addCount(1L,
binCount);
return null;
}
/**
* Copies all of the mappings from the specified map to this one.
* These mappings replace any mappings that this map had for any of the
* keys currently in the specified map.
*
* @param m mappings to be stored in this map
*/
public void
putAll(
Map<? extends K, ? extends V>
m) {
tryPresize(
m.
size());
for (
Map.
Entry<? extends K, ? extends V>
e :
m.
entrySet())
putVal(
e.
getKey(),
e.
getValue(), false);
}
/**
* Removes the key (and its corresponding value) from this map.
* This method does nothing if the key is not in the map.
*
* @param key the key that needs to be removed
* @return the previous value associated with {@code key}, or
* {@code null} if there was no mapping for {@code key}
* @throws NullPointerException if the specified key is null
*/
public V
remove(
Object key) {
return
replaceNode(
key, null, null);
}
/**
* Implementation for the four public remove/replace methods:
* Replaces node value with v, conditional upon match of cv if
* non-null. If resulting value is null, delete.
*/
final V
replaceNode(
Object key, V
value,
Object cv) {
int
hash =
spread(
key.
hashCode());
for (
Node<K,V>[]
tab =
table;;) {
Node<K,V>
f; int
n,
i,
fh;
if (
tab == null || (
n =
tab.length) == 0 ||
(
f =
tabAt(
tab,
i = (
n - 1) &
hash)) == null)
break;
else if ((
fh =
f.
hash) ==
MOVED)
tab =
helpTransfer(
tab,
f);
else {
V
oldVal = null;
boolean
validated = false;
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
if (
fh >= 0) {
validated = true;
for (
Node<K,V>
e =
f,
pred = null;;) {
K
ek;
if (
e.
hash ==
hash &&
((
ek =
e.
key) ==
key ||
(
ek != null &&
key.
equals(
ek)))) {
V
ev =
e.
val;
if (
cv == null ||
cv ==
ev ||
(
ev != null &&
cv.
equals(
ev))) {
oldVal =
ev;
if (
value != null)
e.
val =
value;
else if (
pred != null)
pred.
next =
e.
next;
else
setTabAt(
tab,
i,
e.
next);
}
break;
}
pred =
e;
if ((
e =
e.
next) == null)
break;
}
}
else if (
f instanceof
TreeBin) {
validated = true;
TreeBin<K,V>
t = (
TreeBin<K,V>)
f;
TreeNode<K,V>
r,
p;
if ((
r =
t.
root) != null &&
(
p =
r.
findTreeNode(
hash,
key, null)) != null) {
V
pv =
p.
val;
if (
cv == null ||
cv ==
pv ||
(
pv != null &&
cv.
equals(
pv))) {
oldVal =
pv;
if (
value != null)
p.
val =
value;
else if (
t.
removeTreeNode(
p))
setTabAt(
tab,
i,
untreeify(
t.
first));
}
}
}
}
}
if (
validated) {
if (
oldVal != null) {
if (
value == null)
addCount(-1L, -1);
return
oldVal;
}
break;
}
}
}
return null;
}
/**
* Removes all of the mappings from this map.
*/
public void
clear() {
long
delta = 0L; // negative number of deletions
int
i = 0;
Node<K,V>[]
tab =
table;
while (
tab != null &&
i <
tab.length) {
int
fh;
Node<K,V>
f =
tabAt(
tab,
i);
if (
f == null)
++
i;
else if ((
fh =
f.
hash) ==
MOVED) {
tab =
helpTransfer(
tab,
f);
i = 0; // restart
}
else {
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
Node<K,V>
p = (
fh >= 0 ?
f :
(
f instanceof
TreeBin) ?
((
TreeBin<K,V>)
f).
first : null);
while (
p != null) {
--
delta;
p =
p.
next;
}
setTabAt(
tab,
i++, null);
}
}
}
}
if (
delta != 0L)
addCount(
delta, -1);
}
/**
* Returns a {@link Set} view of the keys contained in this map.
* The set is backed by the map, so changes to the map are
* reflected in the set, and vice-versa. The set supports element
* removal, which removes the corresponding mapping from this map,
* via the {@code Iterator.remove}, {@code Set.remove},
* {@code removeAll}, {@code retainAll}, and {@code clear}
* operations. It does not support the {@code add} or
* {@code addAll} operations.
*
* <p>The view's iterators and spliterators are
* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
*
* <p>The view's {@code spliterator} reports {@link Spliterator#CONCURRENT},
* {@link Spliterator#DISTINCT}, and {@link Spliterator#NONNULL}.
*
* @return the set view
*/
public
KeySetView<K,V>
keySet() {
KeySetView<K,V>
ks;
return (
ks =
keySet) != null ?
ks : (
keySet = new
KeySetView<K,V>(this, null));
}
/**
* Returns a {@link Collection} view of the values contained in this map.
* The collection is backed by the map, so changes to the map are
* reflected in the collection, and vice-versa. The collection
* supports element removal, which removes the corresponding
* mapping from this map, via the {@code Iterator.remove},
* {@code Collection.remove}, {@code removeAll},
* {@code retainAll}, and {@code clear} operations. It does not
* support the {@code add} or {@code addAll} operations.
*
* <p>The view's iterators and spliterators are
* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
*
* <p>The view's {@code spliterator} reports {@link Spliterator#CONCURRENT}
* and {@link Spliterator#NONNULL}.
*
* @return the collection view
*/
public
Collection<V>
values() {
ValuesView<K,V>
vs;
return (
vs =
values) != null ?
vs : (
values = new
ValuesView<K,V>(this));
}
/**
* Returns a {@link Set} view of the mappings contained in this map.
* The set is backed by the map, so changes to the map are
* reflected in the set, and vice-versa. The set supports element
* removal, which removes the corresponding mapping from the map,
* via the {@code Iterator.remove}, {@code Set.remove},
* {@code removeAll}, {@code retainAll}, and {@code clear}
* operations.
*
* <p>The view's iterators and spliterators are
* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
*
* <p>The view's {@code spliterator} reports {@link Spliterator#CONCURRENT},
* {@link Spliterator#DISTINCT}, and {@link Spliterator#NONNULL}.
*
* @return the set view
*/
public
Set<
Map.
Entry<K,V>>
entrySet() {
EntrySetView<K,V>
es;
return (
es =
entrySet) != null ?
es : (
entrySet = new
EntrySetView<K,V>(this));
}
/**
* Returns the hash code value for this {@link Map}, i.e.,
* the sum of, for each key-value pair in the map,
* {@code key.hashCode() ^ value.hashCode()}.
*
* @return the hash code value for this map
*/
public int
hashCode() {
int
h = 0;
Node<K,V>[]
t;
if ((
t =
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; )
h +=
p.
key.
hashCode() ^
p.
val.
hashCode();
}
return
h;
}
/**
* Returns a string representation of this map. The string
* representation consists of a list of key-value mappings (in no
* particular order) enclosed in braces ("{@code {}}"). Adjacent
* mappings are separated by the characters {@code ", "} (comma
* and space). Each key-value mapping is rendered as the key
* followed by an equals sign ("{@code =}") followed by the
* associated value.
*
* @return a string representation of this map
*/
public
String toString() {
Node<K,V>[]
t;
int
f = (
t =
table) == null ? 0 :
t.length;
Traverser<K,V>
it = new
Traverser<K,V>(
t,
f, 0,
f);
StringBuilder sb = new
StringBuilder();
sb.
append('{');
Node<K,V>
p;
if ((
p =
it.
advance()) != null) {
for (;;) {
K
k =
p.
key;
V
v =
p.
val;
sb.
append(
k == this ? "(this Map)" :
k);
sb.
append('=');
sb.
append(
v == this ? "(this Map)" :
v);
if ((
p =
it.
advance()) == null)
break;
sb.
append(',').
append(' ');
}
}
return
sb.
append('}').
toString();
}
/**
* Compares the specified object with this map for equality.
* Returns {@code true} if the given object is a map with the same
* mappings as this map. This operation may return misleading
* results if either map is concurrently modified during execution
* of this method.
*
* @param o object to be compared for equality with this map
* @return {@code true} if the specified object is equal to this map
*/
public boolean
equals(
Object o) {
if (
o != this) {
if (!(
o instanceof
Map))
return false;
Map<?,?>
m = (
Map<?,?>)
o;
Node<K,V>[]
t;
int
f = (
t =
table) == null ? 0 :
t.length;
Traverser<K,V>
it = new
Traverser<K,V>(
t,
f, 0,
f);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; ) {
V
val =
p.
val;
Object v =
m.
get(
p.
key);
if (
v == null || (
v !=
val && !
v.
equals(
val)))
return false;
}
for (
Map.
Entry<?,?>
e :
m.
entrySet()) {
Object mk,
mv,
v;
if ((
mk =
e.
getKey()) == null ||
(
mv =
e.
getValue()) == null ||
(
v =
get(
mk)) == null ||
(
mv !=
v && !
mv.
equals(
v)))
return false;
}
}
return true;
}
/**
* Stripped-down version of helper class used in previous version,
* declared for the sake of serialization compatibility
*/
static class
Segment<K,V> extends
ReentrantLock implements
Serializable {
private static final long
serialVersionUID = 2249069246763182397L;
final float
loadFactor;
Segment(float
lf) { this.
loadFactor =
lf; }
}
/**
* Saves the state of the {@code ConcurrentHashMap} instance to a
* stream (i.e., serializes it).
* @param s the stream
* @throws java.io.IOException if an I/O error occurs
* @serialData
* the key (Object) and value (Object)
* for each key-value mapping, followed by a null pair.
* The key-value mappings are emitted in no particular order.
*/
private void
writeObject(java.io.
ObjectOutputStream s)
throws java.io.
IOException {
// For serialization compatibility
// Emulate segment calculation from previous version of this class
int
sshift = 0;
int
ssize = 1;
while (
ssize <
DEFAULT_CONCURRENCY_LEVEL) {
++
sshift;
ssize <<= 1;
}
int
segmentShift = 32 -
sshift;
int
segmentMask =
ssize - 1;
@
SuppressWarnings("unchecked")
Segment<K,V>[]
segments = (
Segment<K,V>[])
new
Segment<?,?>[
DEFAULT_CONCURRENCY_LEVEL];
for (int
i = 0;
i <
segments.length; ++
i)
segments[
i] = new
Segment<K,V>(
LOAD_FACTOR);
s.
putFields().
put("segments",
segments);
s.
putFields().
put("segmentShift",
segmentShift);
s.
putFields().
put("segmentMask",
segmentMask);
s.
writeFields();
Node<K,V>[]
t;
if ((
t =
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; ) {
s.
writeObject(
p.
key);
s.
writeObject(
p.
val);
}
}
s.
writeObject(null);
s.
writeObject(null);
segments = null; // throw away
}
/**
* Reconstitutes the instance from a stream (that is, deserializes it).
* @param s the stream
* @throws ClassNotFoundException if the class of a serialized object
* could not be found
* @throws java.io.IOException if an I/O error occurs
*/
private void
readObject(java.io.
ObjectInputStream s)
throws java.io.
IOException,
ClassNotFoundException {
/*
* To improve performance in typical cases, we create nodes
* while reading, then place in table once size is known.
* However, we must also validate uniqueness and deal with
* overpopulated bins while doing so, which requires
* specialized versions of putVal mechanics.
*/
sizeCtl = -1; // force exclusion for table construction
s.
defaultReadObject();
long
size = 0L;
Node<K,V>
p = null;
for (;;) {
@
SuppressWarnings("unchecked")
K
k = (K)
s.
readObject();
@
SuppressWarnings("unchecked")
V
v = (V)
s.
readObject();
if (
k != null &&
v != null) {
p = new
Node<K,V>(
spread(
k.
hashCode()),
k,
v,
p);
++
size;
}
else
break;
}
if (
size == 0L)
sizeCtl = 0;
else {
int
n;
if (
size >= (long)(
MAXIMUM_CAPACITY >>> 1))
n =
MAXIMUM_CAPACITY;
else {
int
sz = (int)
size;
n =
tableSizeFor(
sz + (
sz >>> 1) + 1);
}
@
SuppressWarnings("unchecked")
Node<K,V>[]
tab = (
Node<K,V>[])new
Node<?,?>[
n];
int
mask =
n - 1;
long
added = 0L;
while (
p != null) {
boolean
insertAtFront;
Node<K,V>
next =
p.
next,
first;
int
h =
p.
hash,
j =
h &
mask;
if ((
first =
tabAt(
tab,
j)) == null)
insertAtFront = true;
else {
K
k =
p.
key;
if (
first.
hash < 0) {
TreeBin<K,V>
t = (
TreeBin<K,V>)
first;
if (
t.
putTreeVal(
h,
k,
p.
val) == null)
++
added;
insertAtFront = false;
}
else {
int
binCount = 0;
insertAtFront = true;
Node<K,V>
q; K
qk;
for (
q =
first;
q != null;
q =
q.
next) {
if (
q.
hash ==
h &&
((
qk =
q.
key) ==
k ||
(
qk != null &&
k.
equals(
qk)))) {
insertAtFront = false;
break;
}
++
binCount;
}
if (
insertAtFront &&
binCount >=
TREEIFY_THRESHOLD) {
insertAtFront = false;
++
added;
p.
next =
first;
TreeNode<K,V>
hd = null,
tl = null;
for (
q =
p;
q != null;
q =
q.
next) {
TreeNode<K,V>
t = new
TreeNode<K,V>
(
q.
hash,
q.
key,
q.
val, null, null);
if ((
t.
prev =
tl) == null)
hd =
t;
else
tl.
next =
t;
tl =
t;
}
setTabAt(
tab,
j, new
TreeBin<K,V>(
hd));
}
}
}
if (
insertAtFront) {
++
added;
p.
next =
first;
setTabAt(
tab,
j,
p);
}
p =
next;
}
table =
tab;
sizeCtl =
n - (
n >>> 2);
baseCount =
added;
}
}
// ConcurrentMap methods
/**
* {@inheritDoc}
*
* @return the previous value associated with the specified key,
* or {@code null} if there was no mapping for the key
* @throws NullPointerException if the specified key or value is null
*/
public V
putIfAbsent(K
key, V
value) {
return
putVal(
key,
value, true);
}
/**
* {@inheritDoc}
*
* @throws NullPointerException if the specified key is null
*/
public boolean
remove(
Object key,
Object value) {
if (
key == null)
throw new
NullPointerException();
return
value != null &&
replaceNode(
key, null,
value) != null;
}
/**
* {@inheritDoc}
*
* @throws NullPointerException if any of the arguments are null
*/
public boolean
replace(K
key, V
oldValue, V
newValue) {
if (
key == null ||
oldValue == null ||
newValue == null)
throw new
NullPointerException();
return
replaceNode(
key,
newValue,
oldValue) != null;
}
/**
* {@inheritDoc}
*
* @return the previous value associated with the specified key,
* or {@code null} if there was no mapping for the key
* @throws NullPointerException if the specified key or value is null
*/
public V
replace(K
key, V
value) {
if (
key == null ||
value == null)
throw new
NullPointerException();
return
replaceNode(
key,
value, null);
}
// Overrides of JDK8+ Map extension method defaults
/**
* Returns the value to which the specified key is mapped, or the
* given default value if this map contains no mapping for the
* key.
*
* @param key the key whose associated value is to be returned
* @param defaultValue the value to return if this map contains
* no mapping for the given key
* @return the mapping for the key, if present; else the default value
* @throws NullPointerException if the specified key is null
*/
public V
getOrDefault(
Object key, V
defaultValue) {
V
v;
return (
v =
get(
key)) == null ?
defaultValue :
v;
}
public void
forEach(
BiConsumer<? super K, ? super V>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>[]
t;
if ((
t =
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; ) {
action.
accept(
p.
key,
p.
val);
}
}
}
public void
replaceAll(
BiFunction<? super K, ? super V, ? extends V>
function) {
if (
function == null) throw new
NullPointerException();
Node<K,V>[]
t;
if ((
t =
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; ) {
V
oldValue =
p.
val;
for (K
key =
p.
key;;) {
V
newValue =
function.
apply(
key,
oldValue);
if (
newValue == null)
throw new
NullPointerException();
if (
replaceNode(
key,
newValue,
oldValue) != null ||
(
oldValue =
get(
key)) == null)
break;
}
}
}
}
/**
* If the specified key is not already associated with a value,
* attempts to compute its value using the given mapping function
* and enters it into this map unless {@code null}. The entire
* method invocation is performed atomically, so the function is
* applied at most once per key. Some attempted update operations
* on this map by other threads may be blocked while computation
* is in progress, so the computation should be short and simple,
* and must not attempt to update any other mappings of this map.
*
* @param key key with which the specified value is to be associated
* @param mappingFunction the function to compute a value
* @return the current (existing or computed) value associated with
* the specified key, or null if the computed value is null
* @throws NullPointerException if the specified key or mappingFunction
* is null
* @throws IllegalStateException if the computation detectably
* attempts a recursive update to this map that would
* otherwise never complete
* @throws RuntimeException or Error if the mappingFunction does so,
* in which case the mapping is left unestablished
*/
public V
computeIfAbsent(K
key,
Function<? super K, ? extends V>
mappingFunction) {
if (
key == null ||
mappingFunction == null)
throw new
NullPointerException();
int
h =
spread(
key.
hashCode());
V
val = null;
int
binCount = 0;
for (
Node<K,V>[]
tab =
table;;) {
Node<K,V>
f; int
n,
i,
fh;
if (
tab == null || (
n =
tab.length) == 0)
tab =
initTable();
else if ((
f =
tabAt(
tab,
i = (
n - 1) &
h)) == null) {
Node<K,V>
r = new
ReservationNode<K,V>();
synchronized (
r) {
if (
casTabAt(
tab,
i, null,
r)) {
binCount = 1;
Node<K,V>
node = null;
try {
if ((
val =
mappingFunction.
apply(
key)) != null)
node = new
Node<K,V>(
h,
key,
val, null);
} finally {
setTabAt(
tab,
i,
node);
}
}
}
if (
binCount != 0)
break;
}
else if ((
fh =
f.
hash) ==
MOVED)
tab =
helpTransfer(
tab,
f);
else {
boolean
added = false;
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
if (
fh >= 0) {
binCount = 1;
for (
Node<K,V>
e =
f;; ++
binCount) {
K
ek; V
ev;
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
key ||
(
ek != null &&
key.
equals(
ek)))) {
val =
e.
val;
break;
}
Node<K,V>
pred =
e;
if ((
e =
e.
next) == null) {
if ((
val =
mappingFunction.
apply(
key)) != null) {
added = true;
pred.
next = new
Node<K,V>(
h,
key,
val, null);
}
break;
}
}
}
else if (
f instanceof
TreeBin) {
binCount = 2;
TreeBin<K,V>
t = (
TreeBin<K,V>)
f;
TreeNode<K,V>
r,
p;
if ((
r =
t.
root) != null &&
(
p =
r.
findTreeNode(
h,
key, null)) != null)
val =
p.
val;
else if ((
val =
mappingFunction.
apply(
key)) != null) {
added = true;
t.
putTreeVal(
h,
key,
val);
}
}
}
}
if (
binCount != 0) {
if (
binCount >=
TREEIFY_THRESHOLD)
treeifyBin(
tab,
i);
if (!
added)
return
val;
break;
}
}
}
if (
val != null)
addCount(1L,
binCount);
return
val;
}
/**
* If the value for the specified key is present, attempts to
* compute a new mapping given the key and its current mapped
* value. The entire method invocation is performed atomically.
* Some attempted update operations on this map by other threads
* may be blocked while computation is in progress, so the
* computation should be short and simple, and must not attempt to
* update any other mappings of this map.
*
* @param key key with which a value may be associated
* @param remappingFunction the function to compute a value
* @return the new value associated with the specified key, or null if none
* @throws NullPointerException if the specified key or remappingFunction
* is null
* @throws IllegalStateException if the computation detectably
* attempts a recursive update to this map that would
* otherwise never complete
* @throws RuntimeException or Error if the remappingFunction does so,
* in which case the mapping is unchanged
*/
public V
computeIfPresent(K
key,
BiFunction<? super K, ? super V, ? extends V>
remappingFunction) {
if (
key == null ||
remappingFunction == null)
throw new
NullPointerException();
int
h =
spread(
key.
hashCode());
V
val = null;
int
delta = 0;
int
binCount = 0;
for (
Node<K,V>[]
tab =
table;;) {
Node<K,V>
f; int
n,
i,
fh;
if (
tab == null || (
n =
tab.length) == 0)
tab =
initTable();
else if ((
f =
tabAt(
tab,
i = (
n - 1) &
h)) == null)
break;
else if ((
fh =
f.
hash) ==
MOVED)
tab =
helpTransfer(
tab,
f);
else {
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
if (
fh >= 0) {
binCount = 1;
for (
Node<K,V>
e =
f,
pred = null;; ++
binCount) {
K
ek;
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
key ||
(
ek != null &&
key.
equals(
ek)))) {
val =
remappingFunction.
apply(
key,
e.
val);
if (
val != null)
e.
val =
val;
else {
delta = -1;
Node<K,V>
en =
e.
next;
if (
pred != null)
pred.
next =
en;
else
setTabAt(
tab,
i,
en);
}
break;
}
pred =
e;
if ((
e =
e.
next) == null)
break;
}
}
else if (
f instanceof
TreeBin) {
binCount = 2;
TreeBin<K,V>
t = (
TreeBin<K,V>)
f;
TreeNode<K,V>
r,
p;
if ((
r =
t.
root) != null &&
(
p =
r.
findTreeNode(
h,
key, null)) != null) {
val =
remappingFunction.
apply(
key,
p.
val);
if (
val != null)
p.
val =
val;
else {
delta = -1;
if (
t.
removeTreeNode(
p))
setTabAt(
tab,
i,
untreeify(
t.
first));
}
}
}
}
}
if (
binCount != 0)
break;
}
}
if (
delta != 0)
addCount((long)
delta,
binCount);
return
val;
}
/**
* Attempts to compute a mapping for the specified key and its
* current mapped value (or {@code null} if there is no current
* mapping). The entire method invocation is performed atomically.
* Some attempted update operations on this map by other threads
* may be blocked while computation is in progress, so the
* computation should be short and simple, and must not attempt to
* update any other mappings of this Map.
*
* @param key key with which the specified value is to be associated
* @param remappingFunction the function to compute a value
* @return the new value associated with the specified key, or null if none
* @throws NullPointerException if the specified key or remappingFunction
* is null
* @throws IllegalStateException if the computation detectably
* attempts a recursive update to this map that would
* otherwise never complete
* @throws RuntimeException or Error if the remappingFunction does so,
* in which case the mapping is unchanged
*/
public V
compute(K
key,
BiFunction<? super K, ? super V, ? extends V>
remappingFunction) {
if (
key == null ||
remappingFunction == null)
throw new
NullPointerException();
int
h =
spread(
key.
hashCode());
V
val = null;
int
delta = 0;
int
binCount = 0;
for (
Node<K,V>[]
tab =
table;;) {
Node<K,V>
f; int
n,
i,
fh;
if (
tab == null || (
n =
tab.length) == 0)
tab =
initTable();
else if ((
f =
tabAt(
tab,
i = (
n - 1) &
h)) == null) {
Node<K,V>
r = new
ReservationNode<K,V>();
synchronized (
r) {
if (
casTabAt(
tab,
i, null,
r)) {
binCount = 1;
Node<K,V>
node = null;
try {
if ((
val =
remappingFunction.
apply(
key, null)) != null) {
delta = 1;
node = new
Node<K,V>(
h,
key,
val, null);
}
} finally {
setTabAt(
tab,
i,
node);
}
}
}
if (
binCount != 0)
break;
}
else if ((
fh =
f.
hash) ==
MOVED)
tab =
helpTransfer(
tab,
f);
else {
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
if (
fh >= 0) {
binCount = 1;
for (
Node<K,V>
e =
f,
pred = null;; ++
binCount) {
K
ek;
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
key ||
(
ek != null &&
key.
equals(
ek)))) {
val =
remappingFunction.
apply(
key,
e.
val);
if (
val != null)
e.
val =
val;
else {
delta = -1;
Node<K,V>
en =
e.
next;
if (
pred != null)
pred.
next =
en;
else
setTabAt(
tab,
i,
en);
}
break;
}
pred =
e;
if ((
e =
e.
next) == null) {
val =
remappingFunction.
apply(
key, null);
if (
val != null) {
delta = 1;
pred.
next =
new
Node<K,V>(
h,
key,
val, null);
}
break;
}
}
}
else if (
f instanceof
TreeBin) {
binCount = 1;
TreeBin<K,V>
t = (
TreeBin<K,V>)
f;
TreeNode<K,V>
r,
p;
if ((
r =
t.
root) != null)
p =
r.
findTreeNode(
h,
key, null);
else
p = null;
V
pv = (
p == null) ? null :
p.
val;
val =
remappingFunction.
apply(
key,
pv);
if (
val != null) {
if (
p != null)
p.
val =
val;
else {
delta = 1;
t.
putTreeVal(
h,
key,
val);
}
}
else if (
p != null) {
delta = -1;
if (
t.
removeTreeNode(
p))
setTabAt(
tab,
i,
untreeify(
t.
first));
}
}
}
}
if (
binCount != 0) {
if (
binCount >=
TREEIFY_THRESHOLD)
treeifyBin(
tab,
i);
break;
}
}
}
if (
delta != 0)
addCount((long)
delta,
binCount);
return
val;
}
/**
* If the specified key is not already associated with a
* (non-null) value, associates it with the given value.
* Otherwise, replaces the value with the results of the given
* remapping function, or removes if {@code null}. The entire
* method invocation is performed atomically. Some attempted
* update operations on this map by other threads may be blocked
* while computation is in progress, so the computation should be
* short and simple, and must not attempt to update any other
* mappings of this Map.
*
* @param key key with which the specified value is to be associated
* @param value the value to use if absent
* @param remappingFunction the function to recompute a value if present
* @return the new value associated with the specified key, or null if none
* @throws NullPointerException if the specified key or the
* remappingFunction is null
* @throws RuntimeException or Error if the remappingFunction does so,
* in which case the mapping is unchanged
*/
public V
merge(K
key, V
value,
BiFunction<? super V, ? super V, ? extends V>
remappingFunction) {
if (
key == null ||
value == null ||
remappingFunction == null)
throw new
NullPointerException();
int
h =
spread(
key.
hashCode());
V
val = null;
int
delta = 0;
int
binCount = 0;
for (
Node<K,V>[]
tab =
table;;) {
Node<K,V>
f; int
n,
i,
fh;
if (
tab == null || (
n =
tab.length) == 0)
tab =
initTable();
else if ((
f =
tabAt(
tab,
i = (
n - 1) &
h)) == null) {
if (
casTabAt(
tab,
i, null, new
Node<K,V>(
h,
key,
value, null))) {
delta = 1;
val =
value;
break;
}
}
else if ((
fh =
f.
hash) ==
MOVED)
tab =
helpTransfer(
tab,
f);
else {
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
if (
fh >= 0) {
binCount = 1;
for (
Node<K,V>
e =
f,
pred = null;; ++
binCount) {
K
ek;
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
key ||
(
ek != null &&
key.
equals(
ek)))) {
val =
remappingFunction.
apply(
e.
val,
value);
if (
val != null)
e.
val =
val;
else {
delta = -1;
Node<K,V>
en =
e.
next;
if (
pred != null)
pred.
next =
en;
else
setTabAt(
tab,
i,
en);
}
break;
}
pred =
e;
if ((
e =
e.
next) == null) {
delta = 1;
val =
value;
pred.
next =
new
Node<K,V>(
h,
key,
val, null);
break;
}
}
}
else if (
f instanceof
TreeBin) {
binCount = 2;
TreeBin<K,V>
t = (
TreeBin<K,V>)
f;
TreeNode<K,V>
r =
t.
root;
TreeNode<K,V>
p = (
r == null) ? null :
r.
findTreeNode(
h,
key, null);
val = (
p == null) ?
value :
remappingFunction.
apply(
p.
val,
value);
if (
val != null) {
if (
p != null)
p.
val =
val;
else {
delta = 1;
t.
putTreeVal(
h,
key,
val);
}
}
else if (
p != null) {
delta = -1;
if (
t.
removeTreeNode(
p))
setTabAt(
tab,
i,
untreeify(
t.
first));
}
}
}
}
if (
binCount != 0) {
if (
binCount >=
TREEIFY_THRESHOLD)
treeifyBin(
tab,
i);
break;
}
}
}
if (
delta != 0)
addCount((long)
delta,
binCount);
return
val;
}
// Hashtable legacy methods
/**
* Legacy method testing if some key maps into the specified value
* in this table. This method is identical in functionality to
* {@link #containsValue(Object)}, and exists solely to ensure
* full compatibility with class {@link java.util.Hashtable},
* which supported this method prior to introduction of the
* Java Collections framework.
*
* @param value a value to search for
* @return {@code true} if and only if some key maps to the
* {@code value} argument in this table as
* determined by the {@code equals} method;
* {@code false} otherwise
* @throws NullPointerException if the specified value is null
*/
public boolean
contains(
Object value) {
return
containsValue(
value);
}
/**
* Returns an enumeration of the keys in this table.
*
* @return an enumeration of the keys in this table
* @see #keySet()
*/
public
Enumeration<K>
keys() {
Node<K,V>[]
t;
int
f = (
t =
table) == null ? 0 :
t.length;
return new
KeyIterator<K,V>(
t,
f, 0,
f, this);
}
/**
* Returns an enumeration of the values in this table.
*
* @return an enumeration of the values in this table
* @see #values()
*/
public
Enumeration<V>
elements() {
Node<K,V>[]
t;
int
f = (
t =
table) == null ? 0 :
t.length;
return new
ValueIterator<K,V>(
t,
f, 0,
f, this);
}
// ConcurrentHashMap-only methods
/**
* Returns the number of mappings. This method should be used
* instead of {@link #size} because a ConcurrentHashMap may
* contain more mappings than can be represented as an int. The
* value returned is an estimate; the actual count may differ if
* there are concurrent insertions or removals.
*
* @return the number of mappings
* @since 1.8
*/
public long
mappingCount() {
long
n =
sumCount();
return (
n < 0L) ? 0L :
n; // ignore transient negative values
}
/**
* Creates a new {@link Set} backed by a ConcurrentHashMap
* from the given type to {@code Boolean.TRUE}.
*
* @param <K> the element type of the returned set
* @return the new set
* @since 1.8
*/
public static <K>
KeySetView<K,
Boolean>
newKeySet() {
return new
KeySetView<K,
Boolean>
(new
ConcurrentHashMap<K,
Boolean>(),
Boolean.
TRUE);
}
/**
* Creates a new {@link Set} backed by a ConcurrentHashMap
* from the given type to {@code Boolean.TRUE}.
*
* @param initialCapacity The implementation performs internal
* sizing to accommodate this many elements.
* @param <K> the element type of the returned set
* @return the new set
* @throws IllegalArgumentException if the initial capacity of
* elements is negative
* @since 1.8
*/
public static <K>
KeySetView<K,
Boolean>
newKeySet(int
initialCapacity) {
return new
KeySetView<K,
Boolean>
(new
ConcurrentHashMap<K,
Boolean>(
initialCapacity),
Boolean.
TRUE);
}
/**
* Returns a {@link Set} view of the keys in this map, using the
* given common mapped value for any additions (i.e., {@link
* Collection#add} and {@link Collection#addAll(Collection)}).
* This is of course only appropriate if it is acceptable to use
* the same value for all additions from this view.
*
* @param mappedValue the mapped value to use for any additions
* @return the set view
* @throws NullPointerException if the mappedValue is null
*/
public
KeySetView<K,V>
keySet(V
mappedValue) {
if (
mappedValue == null)
throw new
NullPointerException();
return new
KeySetView<K,V>(this,
mappedValue);
}
/* ---------------- Special Nodes -------------- */
/**
* A node inserted at head of bins during transfer operations.
*/
static final class
ForwardingNode<K,V> extends
Node<K,V> {
final
Node<K,V>[]
nextTable;
ForwardingNode(
Node<K,V>[]
tab) {
super(
MOVED, null, null, null);
this.
nextTable =
tab;
}
Node<K,V>
find(int
h,
Object k) {
// loop to avoid arbitrarily deep recursion on forwarding nodes
outer: for (
Node<K,V>[]
tab =
nextTable;;) {
Node<K,V>
e; int
n;
if (
k == null ||
tab == null || (
n =
tab.length) == 0 ||
(
e =
tabAt(
tab, (
n - 1) &
h)) == null)
return null;
for (;;) {
int
eh; K
ek;
if ((
eh =
e.
hash) ==
h &&
((
ek =
e.
key) ==
k || (
ek != null &&
k.
equals(
ek))))
return
e;
if (
eh < 0) {
if (
e instanceof
ForwardingNode) {
tab = ((
ForwardingNode<K,V>)
e).
nextTable;
continue
outer;
}
else
return
e.
find(
h,
k);
}
if ((
e =
e.
next) == null)
return null;
}
}
}
}
/**
* A place-holder node used in computeIfAbsent and compute
*/
static final class
ReservationNode<K,V> extends
Node<K,V> {
ReservationNode() {
super(
RESERVED, null, null, null);
}
Node<K,V>
find(int
h,
Object k) {
return null;
}
}
/* ---------------- Table Initialization and Resizing -------------- */
/**
* Returns the stamp bits for resizing a table of size n.
* Must be negative when shifted left by RESIZE_STAMP_SHIFT.
*/
static final int
resizeStamp(int
n) {
return
Integer.
numberOfLeadingZeros(
n) | (1 << (
RESIZE_STAMP_BITS - 1));
}
/**
* Initializes table, using the size recorded in sizeCtl.
*/
private final
Node<K,V>[]
initTable() {
Node<K,V>[]
tab; int
sc;
while ((
tab =
table) == null ||
tab.length == 0) {
if ((
sc =
sizeCtl) < 0)
Thread.
yield(); // lost initialization race; just spin
else if (
U.
compareAndSwapInt(this,
SIZECTL,
sc, -1)) {
try {
if ((
tab =
table) == null ||
tab.length == 0) {
int
n = (
sc > 0) ?
sc :
DEFAULT_CAPACITY;
@
SuppressWarnings("unchecked")
Node<K,V>[]
nt = (
Node<K,V>[])new
Node<?,?>[
n];
table =
tab =
nt;
sc =
n - (
n >>> 2);
}
} finally {
sizeCtl =
sc;
}
break;
}
}
return
tab;
}
/**
* Adds to count, and if table is too small and not already
* resizing, initiates transfer. If already resizing, helps
* perform transfer if work is available. Rechecks occupancy
* after a transfer to see if another resize is already needed
* because resizings are lagging additions.
*
* @param x the count to add
* @param check if <0, don't check resize, if <= 1 only check if uncontended
*/
private final void
addCount(long
x, int
check) {
CounterCell[]
as; long
b,
s;
if ((
as =
counterCells) != null ||
!
U.
compareAndSwapLong(this,
BASECOUNT,
b =
baseCount,
s =
b +
x)) {
CounterCell a; long
v; int
m;
boolean
uncontended = true;
if (
as == null || (
m =
as.length - 1) < 0 ||
(
a =
as[
ThreadLocalRandom.
getProbe() &
m]) == null ||
!(
uncontended =
U.
compareAndSwapLong(
a,
CELLVALUE,
v =
a.
value,
v +
x))) {
fullAddCount(
x,
uncontended);
return;
}
if (
check <= 1)
return;
s =
sumCount();
}
if (
check >= 0) {
Node<K,V>[]
tab,
nt; int
n,
sc;
while (
s >= (long)(
sc =
sizeCtl) && (
tab =
table) != null &&
(
n =
tab.length) <
MAXIMUM_CAPACITY) {
int
rs =
resizeStamp(
n);
if (
sc < 0) {
if ((
sc >>>
RESIZE_STAMP_SHIFT) !=
rs ||
sc ==
rs + 1 ||
sc ==
rs +
MAX_RESIZERS || (
nt =
nextTable) == null ||
transferIndex <= 0)
break;
if (
U.
compareAndSwapInt(this,
SIZECTL,
sc,
sc + 1))
transfer(
tab,
nt);
}
else if (
U.
compareAndSwapInt(this,
SIZECTL,
sc,
(
rs <<
RESIZE_STAMP_SHIFT) + 2))
transfer(
tab, null);
s =
sumCount();
}
}
}
/**
* Helps transfer if a resize is in progress.
*/
final
Node<K,V>[]
helpTransfer(
Node<K,V>[]
tab,
Node<K,V>
f) {
Node<K,V>[]
nextTab; int
sc;
if (
tab != null && (
f instanceof
ForwardingNode) &&
(
nextTab = ((
ForwardingNode<K,V>)
f).
nextTable) != null) {
int
rs =
resizeStamp(
tab.length);
while (
nextTab ==
nextTable &&
table ==
tab &&
(
sc =
sizeCtl) < 0) {
if ((
sc >>>
RESIZE_STAMP_SHIFT) !=
rs ||
sc ==
rs + 1 ||
sc ==
rs +
MAX_RESIZERS ||
transferIndex <= 0)
break;
if (
U.
compareAndSwapInt(this,
SIZECTL,
sc,
sc + 1)) {
transfer(
tab,
nextTab);
break;
}
}
return
nextTab;
}
return
table;
}
/**
* Tries to presize table to accommodate the given number of elements.
*
* @param size number of elements (doesn't need to be perfectly accurate)
*/
private final void
tryPresize(int
size) {
int
c = (
size >= (
MAXIMUM_CAPACITY >>> 1)) ?
MAXIMUM_CAPACITY :
tableSizeFor(
size + (
size >>> 1) + 1);
int
sc;
while ((
sc =
sizeCtl) >= 0) {
Node<K,V>[]
tab =
table; int
n;
if (
tab == null || (
n =
tab.length) == 0) {
n = (
sc >
c) ?
sc :
c;
if (
U.
compareAndSwapInt(this,
SIZECTL,
sc, -1)) {
try {
if (
table ==
tab) {
@
SuppressWarnings("unchecked")
Node<K,V>[]
nt = (
Node<K,V>[])new
Node<?,?>[
n];
table =
nt;
sc =
n - (
n >>> 2);
}
} finally {
sizeCtl =
sc;
}
}
}
else if (
c <=
sc ||
n >=
MAXIMUM_CAPACITY)
break;
else if (
tab ==
table) {
int
rs =
resizeStamp(
n);
if (
sc < 0) {
Node<K,V>[]
nt;
if ((
sc >>>
RESIZE_STAMP_SHIFT) !=
rs ||
sc ==
rs + 1 ||
sc ==
rs +
MAX_RESIZERS || (
nt =
nextTable) == null ||
transferIndex <= 0)
break;
if (
U.
compareAndSwapInt(this,
SIZECTL,
sc,
sc + 1))
transfer(
tab,
nt);
}
else if (
U.
compareAndSwapInt(this,
SIZECTL,
sc,
(
rs <<
RESIZE_STAMP_SHIFT) + 2))
transfer(
tab, null);
}
}
}
/**
* Moves and/or copies the nodes in each bin to new table. See
* above for explanation.
*/
private final void
transfer(
Node<K,V>[]
tab,
Node<K,V>[]
nextTab) {
int
n =
tab.length,
stride;
if ((
stride = (
NCPU > 1) ? (
n >>> 3) /
NCPU :
n) <
MIN_TRANSFER_STRIDE)
stride =
MIN_TRANSFER_STRIDE; // subdivide range
if (
nextTab == null) { // initiating
try {
@
SuppressWarnings("unchecked")
Node<K,V>[]
nt = (
Node<K,V>[])new
Node<?,?>[
n << 1];
nextTab =
nt;
} catch (
Throwable ex) { // try to cope with OOME
sizeCtl =
Integer.
MAX_VALUE;
return;
}
nextTable =
nextTab;
transferIndex =
n;
}
int
nextn =
nextTab.length;
ForwardingNode<K,V>
fwd = new
ForwardingNode<K,V>(
nextTab);
boolean
advance = true;
boolean
finishing = false; // to ensure sweep before committing nextTab
for (int
i = 0,
bound = 0;;) {
Node<K,V>
f; int
fh;
while (
advance) {
int
nextIndex,
nextBound;
if (--
i >=
bound ||
finishing)
advance = false;
else if ((
nextIndex =
transferIndex) <= 0) {
i = -1;
advance = false;
}
else if (
U.
compareAndSwapInt
(this,
TRANSFERINDEX,
nextIndex,
nextBound = (
nextIndex >
stride ?
nextIndex -
stride : 0))) {
bound =
nextBound;
i =
nextIndex - 1;
advance = false;
}
}
if (
i < 0 ||
i >=
n ||
i +
n >=
nextn) {
int
sc;
if (
finishing) {
nextTable = null;
table =
nextTab;
sizeCtl = (
n << 1) - (
n >>> 1);
return;
}
if (
U.
compareAndSwapInt(this,
SIZECTL,
sc =
sizeCtl,
sc - 1)) {
if ((
sc - 2) !=
resizeStamp(
n) <<
RESIZE_STAMP_SHIFT)
return;
finishing =
advance = true;
i =
n; // recheck before commit
}
}
else if ((
f =
tabAt(
tab,
i)) == null)
advance =
casTabAt(
tab,
i, null,
fwd);
else if ((
fh =
f.
hash) ==
MOVED)
advance = true; // already processed
else {
synchronized (
f) {
if (
tabAt(
tab,
i) ==
f) {
Node<K,V>
ln,
hn;
if (
fh >= 0) {
int
runBit =
fh &
n;
Node<K,V>
lastRun =
f;
for (
Node<K,V>
p =
f.
next;
p != null;
p =
p.
next) {
int
b =
p.
hash &
n;
if (
b !=
runBit) {
runBit =
b;
lastRun =
p;
}
}
if (
runBit == 0) {
ln =
lastRun;
hn = null;
}
else {
hn =
lastRun;
ln = null;
}
for (
Node<K,V>
p =
f;
p !=
lastRun;
p =
p.
next) {
int
ph =
p.
hash; K
pk =
p.
key; V
pv =
p.
val;
if ((
ph &
n) == 0)
ln = new
Node<K,V>(
ph,
pk,
pv,
ln);
else
hn = new
Node<K,V>(
ph,
pk,
pv,
hn);
}
setTabAt(
nextTab,
i,
ln);
setTabAt(
nextTab,
i +
n,
hn);
setTabAt(
tab,
i,
fwd);
advance = true;
}
else if (
f instanceof
TreeBin) {
TreeBin<K,V>
t = (
TreeBin<K,V>)
f;
TreeNode<K,V>
lo = null,
loTail = null;
TreeNode<K,V>
hi = null,
hiTail = null;
int
lc = 0,
hc = 0;
for (
Node<K,V>
e =
t.
first;
e != null;
e =
e.
next) {
int
h =
e.
hash;
TreeNode<K,V>
p = new
TreeNode<K,V>
(
h,
e.
key,
e.
val, null, null);
if ((
h &
n) == 0) {
if ((
p.
prev =
loTail) == null)
lo =
p;
else
loTail.
next =
p;
loTail =
p;
++
lc;
}
else {
if ((
p.
prev =
hiTail) == null)
hi =
p;
else
hiTail.
next =
p;
hiTail =
p;
++
hc;
}
}
ln = (
lc <=
UNTREEIFY_THRESHOLD) ?
untreeify(
lo) :
(
hc != 0) ? new
TreeBin<K,V>(
lo) :
t;
hn = (
hc <=
UNTREEIFY_THRESHOLD) ?
untreeify(
hi) :
(
lc != 0) ? new
TreeBin<K,V>(
hi) :
t;
setTabAt(
nextTab,
i,
ln);
setTabAt(
nextTab,
i +
n,
hn);
setTabAt(
tab,
i,
fwd);
advance = true;
}
}
}
}
}
}
/* ---------------- Counter support -------------- */
/**
* A padded cell for distributing counts. Adapted from LongAdder
* and Striped64. See their internal docs for explanation.
*/
@sun.misc.
Contended static final class
CounterCell {
volatile long
value;
CounterCell(long
x) {
value =
x; }
}
final long
sumCount() {
CounterCell[]
as =
counterCells;
CounterCell a;
long
sum =
baseCount;
if (
as != null) {
for (int
i = 0;
i <
as.length; ++
i) {
if ((
a =
as[
i]) != null)
sum +=
a.
value;
}
}
return
sum;
}
// See LongAdder version for explanation
private final void
fullAddCount(long
x, boolean
wasUncontended) {
int
h;
if ((
h =
ThreadLocalRandom.
getProbe()) == 0) {
ThreadLocalRandom.
localInit(); // force initialization
h =
ThreadLocalRandom.
getProbe();
wasUncontended = true;
}
boolean
collide = false; // True if last slot nonempty
for (;;) {
CounterCell[]
as;
CounterCell a; int
n; long
v;
if ((
as =
counterCells) != null && (
n =
as.length) > 0) {
if ((
a =
as[(
n - 1) &
h]) == null) {
if (
cellsBusy == 0) { // Try to attach new Cell
CounterCell r = new
CounterCell(
x); // Optimistic create
if (
cellsBusy == 0 &&
U.
compareAndSwapInt(this,
CELLSBUSY, 0, 1)) {
boolean
created = false;
try { // Recheck under lock
CounterCell[]
rs; int
m,
j;
if ((
rs =
counterCells) != null &&
(
m =
rs.length) > 0 &&
rs[
j = (
m - 1) &
h] == null) {
rs[
j] =
r;
created = true;
}
} finally {
cellsBusy = 0;
}
if (
created)
break;
continue; // Slot is now non-empty
}
}
collide = false;
}
else if (!
wasUncontended) // CAS already known to fail
wasUncontended = true; // Continue after rehash
else if (
U.
compareAndSwapLong(
a,
CELLVALUE,
v =
a.
value,
v +
x))
break;
else if (
counterCells !=
as ||
n >=
NCPU)
collide = false; // At max size or stale
else if (!
collide)
collide = true;
else if (
cellsBusy == 0 &&
U.
compareAndSwapInt(this,
CELLSBUSY, 0, 1)) {
try {
if (
counterCells ==
as) {// Expand table unless stale
CounterCell[]
rs = new
CounterCell[
n << 1];
for (int
i = 0;
i <
n; ++
i)
rs[
i] =
as[
i];
counterCells =
rs;
}
} finally {
cellsBusy = 0;
}
collide = false;
continue; // Retry with expanded table
}
h =
ThreadLocalRandom.
advanceProbe(
h);
}
else if (
cellsBusy == 0 &&
counterCells ==
as &&
U.
compareAndSwapInt(this,
CELLSBUSY, 0, 1)) {
boolean
init = false;
try { // Initialize table
if (
counterCells ==
as) {
CounterCell[]
rs = new
CounterCell[2];
rs[
h & 1] = new
CounterCell(
x);
counterCells =
rs;
init = true;
}
} finally {
cellsBusy = 0;
}
if (
init)
break;
}
else if (
U.
compareAndSwapLong(this,
BASECOUNT,
v =
baseCount,
v +
x))
break; // Fall back on using base
}
}
/* ---------------- Conversion from/to TreeBins -------------- */
/**
* Replaces all linked nodes in bin at given index unless table is
* too small, in which case resizes instead.
*/
private final void
treeifyBin(
Node<K,V>[]
tab, int
index) {
Node<K,V>
b; int
n,
sc;
if (
tab != null) {
if ((
n =
tab.length) <
MIN_TREEIFY_CAPACITY)
tryPresize(
n << 1);
else if ((
b =
tabAt(
tab,
index)) != null &&
b.
hash >= 0) {
synchronized (
b) {
if (
tabAt(
tab,
index) ==
b) {
TreeNode<K,V>
hd = null,
tl = null;
for (
Node<K,V>
e =
b;
e != null;
e =
e.
next) {
TreeNode<K,V>
p =
new
TreeNode<K,V>(
e.
hash,
e.
key,
e.
val,
null, null);
if ((
p.
prev =
tl) == null)
hd =
p;
else
tl.
next =
p;
tl =
p;
}
setTabAt(
tab,
index, new
TreeBin<K,V>(
hd));
}
}
}
}
}
/**
* Returns a list on non-TreeNodes replacing those in given list.
*/
static <K,V>
Node<K,V>
untreeify(
Node<K,V>
b) {
Node<K,V>
hd = null,
tl = null;
for (
Node<K,V>
q =
b;
q != null;
q =
q.
next) {
Node<K,V>
p = new
Node<K,V>(
q.
hash,
q.
key,
q.
val, null);
if (
tl == null)
hd =
p;
else
tl.
next =
p;
tl =
p;
}
return
hd;
}
/* ---------------- TreeNodes -------------- */
/**
* Nodes for use in TreeBins
*/
static final class
TreeNode<K,V> extends
Node<K,V> {
TreeNode<K,V>
parent; // red-black tree links
TreeNode<K,V>
left;
TreeNode<K,V>
right;
TreeNode<K,V>
prev; // needed to unlink next upon deletion
boolean
red;
TreeNode(int
hash, K
key, V
val,
Node<K,V>
next,
TreeNode<K,V>
parent) {
super(
hash,
key,
val,
next);
this.
parent =
parent;
}
Node<K,V>
find(int
h,
Object k) {
return
findTreeNode(
h,
k, null);
}
/**
* Returns the TreeNode (or null if not found) for the given key
* starting at given root.
*/
final
TreeNode<K,V>
findTreeNode(int
h,
Object k,
Class<?>
kc) {
if (
k != null) {
TreeNode<K,V>
p = this;
do {
int
ph,
dir; K
pk;
TreeNode<K,V>
q;
TreeNode<K,V>
pl =
p.
left,
pr =
p.
right;
if ((
ph =
p.
hash) >
h)
p =
pl;
else if (
ph <
h)
p =
pr;
else if ((
pk =
p.
key) ==
k || (
pk != null &&
k.
equals(
pk)))
return
p;
else if (
pl == null)
p =
pr;
else if (
pr == null)
p =
pl;
else if ((
kc != null ||
(
kc =
comparableClassFor(
k)) != null) &&
(
dir =
compareComparables(
kc,
k,
pk)) != 0)
p = (
dir < 0) ?
pl :
pr;
else if ((
q =
pr.
findTreeNode(
h,
k,
kc)) != null)
return
q;
else
p =
pl;
} while (
p != null);
}
return null;
}
}
/* ---------------- TreeBins -------------- */
/**
* TreeNodes used at the heads of bins. TreeBins do not hold user
* keys or values, but instead point to list of TreeNodes and
* their root. They also maintain a parasitic read-write lock
* forcing writers (who hold bin lock) to wait for readers (who do
* not) to complete before tree restructuring operations.
*/
static final class
TreeBin<K,V> extends
Node<K,V> {
TreeNode<K,V>
root;
volatile
TreeNode<K,V>
first;
volatile
Thread waiter;
volatile int
lockState;
// values for lockState
static final int
WRITER = 1; // set while holding write lock
static final int
WAITER = 2; // set when waiting for write lock
static final int
READER = 4; // increment value for setting read lock
/**
* Tie-breaking utility for ordering insertions when equal
* hashCodes and non-comparable. We don't require a total
* order, just a consistent insertion rule to maintain
* equivalence across rebalancings. Tie-breaking further than
* necessary simplifies testing a bit.
*/
static int
tieBreakOrder(
Object a,
Object b) {
int
d;
if (
a == null ||
b == null ||
(
d =
a.
getClass().
getName().
compareTo(
b.
getClass().
getName())) == 0)
d = (
System.
identityHashCode(
a) <=
System.
identityHashCode(
b) ?
-1 : 1);
return
d;
}
/**
* Creates bin with initial set of nodes headed by b.
*/
TreeBin(
TreeNode<K,V>
b) {
super(
TREEBIN, null, null, null);
this.
first =
b;
TreeNode<K,V>
r = null;
for (
TreeNode<K,V>
x =
b,
next;
x != null;
x =
next) {
next = (
TreeNode<K,V>)
x.
next;
x.
left =
x.
right = null;
if (
r == null) {
x.
parent = null;
x.
red = false;
r =
x;
}
else {
K
k =
x.
key;
int
h =
x.
hash;
Class<?>
kc = null;
for (
TreeNode<K,V>
p =
r;;) {
int
dir,
ph;
K
pk =
p.
key;
if ((
ph =
p.
hash) >
h)
dir = -1;
else if (
ph <
h)
dir = 1;
else if ((
kc == null &&
(
kc =
comparableClassFor(
k)) == null) ||
(
dir =
compareComparables(
kc,
k,
pk)) == 0)
dir =
tieBreakOrder(
k,
pk);
TreeNode<K,V>
xp =
p;
if ((
p = (
dir <= 0) ?
p.
left :
p.
right) == null) {
x.
parent =
xp;
if (
dir <= 0)
xp.
left =
x;
else
xp.
right =
x;
r =
balanceInsertion(
r,
x);
break;
}
}
}
}
this.
root =
r;
assert
checkInvariants(
root);
}
/**
* Acquires write lock for tree restructuring.
*/
private final void
lockRoot() {
if (!
U.
compareAndSwapInt(this,
LOCKSTATE, 0,
WRITER))
contendedLock(); // offload to separate method
}
/**
* Releases write lock for tree restructuring.
*/
private final void
unlockRoot() {
lockState = 0;
}
/**
* Possibly blocks awaiting root lock.
*/
private final void
contendedLock() {
boolean
waiting = false;
for (int
s;;) {
if (((
s =
lockState) & ~
WAITER) == 0) {
if (
U.
compareAndSwapInt(this,
LOCKSTATE,
s,
WRITER)) {
if (
waiting)
waiter = null;
return;
}
}
else if ((
s &
WAITER) == 0) {
if (
U.
compareAndSwapInt(this,
LOCKSTATE,
s,
s |
WAITER)) {
waiting = true;
waiter =
Thread.
currentThread();
}
}
else if (
waiting)
LockSupport.
park(this);
}
}
/**
* Returns matching node or null if none. Tries to search
* using tree comparisons from root, but continues linear
* search when lock not available.
*/
final
Node<K,V>
find(int
h,
Object k) {
if (
k != null) {
for (
Node<K,V>
e =
first;
e != null; ) {
int
s; K
ek;
if (((
s =
lockState) & (
WAITER|
WRITER)) != 0) {
if (
e.
hash ==
h &&
((
ek =
e.
key) ==
k || (
ek != null &&
k.
equals(
ek))))
return
e;
e =
e.
next;
}
else if (
U.
compareAndSwapInt(this,
LOCKSTATE,
s,
s +
READER)) {
TreeNode<K,V>
r,
p;
try {
p = ((
r =
root) == null ? null :
r.
findTreeNode(
h,
k, null));
} finally {
Thread w;
if (
U.
getAndAddInt(this,
LOCKSTATE, -
READER) ==
(
READER|
WAITER) && (
w =
waiter) != null)
LockSupport.
unpark(
w);
}
return
p;
}
}
}
return null;
}
/**
* Finds or adds a node.
* @return null if added
*/
final
TreeNode<K,V>
putTreeVal(int
h, K
k, V
v) {
Class<?>
kc = null;
boolean
searched = false;
for (
TreeNode<K,V>
p =
root;;) {
int
dir,
ph; K
pk;
if (
p == null) {
first =
root = new
TreeNode<K,V>(
h,
k,
v, null, null);
break;
}
else if ((
ph =
p.
hash) >
h)
dir = -1;
else if (
ph <
h)
dir = 1;
else if ((
pk =
p.
key) ==
k || (
pk != null &&
k.
equals(
pk)))
return
p;
else if ((
kc == null &&
(
kc =
comparableClassFor(
k)) == null) ||
(
dir =
compareComparables(
kc,
k,
pk)) == 0) {
if (!
searched) {
TreeNode<K,V>
q,
ch;
searched = true;
if (((
ch =
p.
left) != null &&
(
q =
ch.
findTreeNode(
h,
k,
kc)) != null) ||
((
ch =
p.
right) != null &&
(
q =
ch.
findTreeNode(
h,
k,
kc)) != null))
return
q;
}
dir =
tieBreakOrder(
k,
pk);
}
TreeNode<K,V>
xp =
p;
if ((
p = (
dir <= 0) ?
p.
left :
p.
right) == null) {
TreeNode<K,V>
x,
f =
first;
first =
x = new
TreeNode<K,V>(
h,
k,
v,
f,
xp);
if (
f != null)
f.
prev =
x;
if (
dir <= 0)
xp.
left =
x;
else
xp.
right =
x;
if (!
xp.
red)
x.
red = true;
else {
lockRoot();
try {
root =
balanceInsertion(
root,
x);
} finally {
unlockRoot();
}
}
break;
}
}
assert
checkInvariants(
root);
return null;
}
/**
* Removes the given node, that must be present before this
* call. This is messier than typical red-black deletion code
* because we cannot swap the contents of an interior node
* with a leaf successor that is pinned by "next" pointers
* that are accessible independently of lock. So instead we
* swap the tree linkages.
*
* @return true if now too small, so should be untreeified
*/
final boolean
removeTreeNode(
TreeNode<K,V>
p) {
TreeNode<K,V>
next = (
TreeNode<K,V>)
p.
next;
TreeNode<K,V>
pred =
p.
prev; // unlink traversal pointers
TreeNode<K,V>
r,
rl;
if (
pred == null)
first =
next;
else
pred.
next =
next;
if (
next != null)
next.
prev =
pred;
if (
first == null) {
root = null;
return true;
}
if ((
r =
root) == null ||
r.
right == null || // too small
(
rl =
r.
left) == null ||
rl.
left == null)
return true;
lockRoot();
try {
TreeNode<K,V>
replacement;
TreeNode<K,V>
pl =
p.
left;
TreeNode<K,V>
pr =
p.
right;
if (
pl != null &&
pr != null) {
TreeNode<K,V>
s =
pr,
sl;
while ((
sl =
s.
left) != null) // find successor
s =
sl;
boolean
c =
s.
red;
s.
red =
p.
red;
p.
red =
c; // swap colors
TreeNode<K,V>
sr =
s.
right;
TreeNode<K,V>
pp =
p.
parent;
if (
s ==
pr) { // p was s's direct parent
p.
parent =
s;
s.
right =
p;
}
else {
TreeNode<K,V>
sp =
s.
parent;
if ((
p.
parent =
sp) != null) {
if (
s ==
sp.
left)
sp.
left =
p;
else
sp.
right =
p;
}
if ((
s.
right =
pr) != null)
pr.
parent =
s;
}
p.
left = null;
if ((
p.
right =
sr) != null)
sr.
parent =
p;
if ((
s.
left =
pl) != null)
pl.
parent =
s;
if ((
s.
parent =
pp) == null)
r =
s;
else if (
p ==
pp.
left)
pp.
left =
s;
else
pp.
right =
s;
if (
sr != null)
replacement =
sr;
else
replacement =
p;
}
else if (
pl != null)
replacement =
pl;
else if (
pr != null)
replacement =
pr;
else
replacement =
p;
if (
replacement !=
p) {
TreeNode<K,V>
pp =
replacement.
parent =
p.
parent;
if (
pp == null)
r =
replacement;
else if (
p ==
pp.
left)
pp.
left =
replacement;
else
pp.
right =
replacement;
p.
left =
p.
right =
p.
parent = null;
}
root = (
p.
red) ?
r :
balanceDeletion(
r,
replacement);
if (
p ==
replacement) { // detach pointers
TreeNode<K,V>
pp;
if ((
pp =
p.
parent) != null) {
if (
p ==
pp.
left)
pp.
left = null;
else if (
p ==
pp.
right)
pp.
right = null;
p.
parent = null;
}
}
} finally {
unlockRoot();
}
assert
checkInvariants(
root);
return false;
}
/* ------------------------------------------------------------ */
// Red-black tree methods, all adapted from CLR
static <K,V>
TreeNode<K,V>
rotateLeft(
TreeNode<K,V>
root,
TreeNode<K,V>
p) {
TreeNode<K,V>
r,
pp,
rl;
if (
p != null && (
r =
p.
right) != null) {
if ((
rl =
p.
right =
r.
left) != null)
rl.
parent =
p;
if ((
pp =
r.
parent =
p.
parent) == null)
(
root =
r).
red = false;
else if (
pp.
left ==
p)
pp.
left =
r;
else
pp.
right =
r;
r.
left =
p;
p.
parent =
r;
}
return
root;
}
static <K,V>
TreeNode<K,V>
rotateRight(
TreeNode<K,V>
root,
TreeNode<K,V>
p) {
TreeNode<K,V>
l,
pp,
lr;
if (
p != null && (
l =
p.
left) != null) {
if ((
lr =
p.
left =
l.
right) != null)
lr.
parent =
p;
if ((
pp =
l.
parent =
p.
parent) == null)
(
root =
l).
red = false;
else if (
pp.
right ==
p)
pp.
right =
l;
else
pp.
left =
l;
l.
right =
p;
p.
parent =
l;
}
return
root;
}
static <K,V>
TreeNode<K,V>
balanceInsertion(
TreeNode<K,V>
root,
TreeNode<K,V>
x) {
x.
red = true;
for (
TreeNode<K,V>
xp,
xpp,
xppl,
xppr;;) {
if ((
xp =
x.
parent) == null) {
x.
red = false;
return
x;
}
else if (!
xp.
red || (
xpp =
xp.
parent) == null)
return
root;
if (
xp == (
xppl =
xpp.
left)) {
if ((
xppr =
xpp.
right) != null &&
xppr.
red) {
xppr.
red = false;
xp.
red = false;
xpp.
red = true;
x =
xpp;
}
else {
if (
x ==
xp.
right) {
root =
rotateLeft(
root,
x =
xp);
xpp = (
xp =
x.
parent) == null ? null :
xp.
parent;
}
if (
xp != null) {
xp.
red = false;
if (
xpp != null) {
xpp.
red = true;
root =
rotateRight(
root,
xpp);
}
}
}
}
else {
if (
xppl != null &&
xppl.
red) {
xppl.
red = false;
xp.
red = false;
xpp.
red = true;
x =
xpp;
}
else {
if (
x ==
xp.
left) {
root =
rotateRight(
root,
x =
xp);
xpp = (
xp =
x.
parent) == null ? null :
xp.
parent;
}
if (
xp != null) {
xp.
red = false;
if (
xpp != null) {
xpp.
red = true;
root =
rotateLeft(
root,
xpp);
}
}
}
}
}
}
static <K,V>
TreeNode<K,V>
balanceDeletion(
TreeNode<K,V>
root,
TreeNode<K,V>
x) {
for (
TreeNode<K,V>
xp,
xpl,
xpr;;) {
if (
x == null ||
x ==
root)
return
root;
else if ((
xp =
x.
parent) == null) {
x.
red = false;
return
x;
}
else if (
x.
red) {
x.
red = false;
return
root;
}
else if ((
xpl =
xp.
left) ==
x) {
if ((
xpr =
xp.
right) != null &&
xpr.
red) {
xpr.
red = false;
xp.
red = true;
root =
rotateLeft(
root,
xp);
xpr = (
xp =
x.
parent) == null ? null :
xp.
right;
}
if (
xpr == null)
x =
xp;
else {
TreeNode<K,V>
sl =
xpr.
left,
sr =
xpr.
right;
if ((
sr == null || !
sr.
red) &&
(
sl == null || !
sl.
red)) {
xpr.
red = true;
x =
xp;
}
else {
if (
sr == null || !
sr.
red) {
if (
sl != null)
sl.
red = false;
xpr.
red = true;
root =
rotateRight(
root,
xpr);
xpr = (
xp =
x.
parent) == null ?
null :
xp.
right;
}
if (
xpr != null) {
xpr.
red = (
xp == null) ? false :
xp.
red;
if ((
sr =
xpr.
right) != null)
sr.
red = false;
}
if (
xp != null) {
xp.
red = false;
root =
rotateLeft(
root,
xp);
}
x =
root;
}
}
}
else { // symmetric
if (
xpl != null &&
xpl.
red) {
xpl.
red = false;
xp.
red = true;
root =
rotateRight(
root,
xp);
xpl = (
xp =
x.
parent) == null ? null :
xp.
left;
}
if (
xpl == null)
x =
xp;
else {
TreeNode<K,V>
sl =
xpl.
left,
sr =
xpl.
right;
if ((
sl == null || !
sl.
red) &&
(
sr == null || !
sr.
red)) {
xpl.
red = true;
x =
xp;
}
else {
if (
sl == null || !
sl.
red) {
if (
sr != null)
sr.
red = false;
xpl.
red = true;
root =
rotateLeft(
root,
xpl);
xpl = (
xp =
x.
parent) == null ?
null :
xp.
left;
}
if (
xpl != null) {
xpl.
red = (
xp == null) ? false :
xp.
red;
if ((
sl =
xpl.
left) != null)
sl.
red = false;
}
if (
xp != null) {
xp.
red = false;
root =
rotateRight(
root,
xp);
}
x =
root;
}
}
}
}
}
/**
* Recursive invariant check
*/
static <K,V> boolean
checkInvariants(
TreeNode<K,V>
t) {
TreeNode<K,V>
tp =
t.
parent,
tl =
t.
left,
tr =
t.
right,
tb =
t.
prev,
tn = (
TreeNode<K,V>)
t.
next;
if (
tb != null &&
tb.
next !=
t)
return false;
if (
tn != null &&
tn.
prev !=
t)
return false;
if (
tp != null &&
t !=
tp.
left &&
t !=
tp.
right)
return false;
if (
tl != null && (
tl.
parent !=
t ||
tl.
hash >
t.
hash))
return false;
if (
tr != null && (
tr.
parent !=
t ||
tr.
hash <
t.
hash))
return false;
if (
t.
red &&
tl != null &&
tl.
red &&
tr != null &&
tr.
red)
return false;
if (
tl != null && !
checkInvariants(
tl))
return false;
if (
tr != null && !
checkInvariants(
tr))
return false;
return true;
}
private static final sun.misc.
Unsafe U;
private static final long
LOCKSTATE;
static {
try {
U = sun.misc.
Unsafe.
getUnsafe();
Class<?>
k =
TreeBin.class;
LOCKSTATE =
U.
objectFieldOffset
(
k.
getDeclaredField("lockState"));
} catch (
Exception e) {
throw new
Error(
e);
}
}
}
/* ----------------Table Traversal -------------- */
/**
* Records the table, its length, and current traversal index for a
* traverser that must process a region of a forwarded table before
* proceeding with current table.
*/
static final class
TableStack<K,V> {
int
length;
int
index;
Node<K,V>[]
tab;
TableStack<K,V>
next;
}
/**
* Encapsulates traversal for methods such as containsValue; also
* serves as a base class for other iterators and spliterators.
*
* Method advance visits once each still-valid node that was
* reachable upon iterator construction. It might miss some that
* were added to a bin after the bin was visited, which is OK wrt
* consistency guarantees. Maintaining this property in the face
* of possible ongoing resizes requires a fair amount of
* bookkeeping state that is difficult to optimize away amidst
* volatile accesses. Even so, traversal maintains reasonable
* throughput.
*
* Normally, iteration proceeds bin-by-bin traversing lists.
* However, if the table has been resized, then all future steps
* must traverse both the bin at the current index as well as at
* (index + baseSize); and so on for further resizings. To
* paranoically cope with potential sharing by users of iterators
* across threads, iteration terminates if a bounds checks fails
* for a table read.
*/
static class
Traverser<K,V> {
Node<K,V>[]
tab; // current table; updated if resized
Node<K,V>
next; // the next entry to use
TableStack<K,V>
stack,
spare; // to save/restore on ForwardingNodes
int
index; // index of bin to use next
int
baseIndex; // current index of initial table
int
baseLimit; // index bound for initial table
final int
baseSize; // initial table size
Traverser(
Node<K,V>[]
tab, int
size, int
index, int
limit) {
this.
tab =
tab;
this.
baseSize =
size;
this.
baseIndex = this.
index =
index;
this.
baseLimit =
limit;
this.
next = null;
}
/**
* Advances if possible, returning next valid node, or null if none.
*/
final
Node<K,V>
advance() {
Node<K,V>
e;
if ((
e =
next) != null)
e =
e.
next;
for (;;) {
Node<K,V>[]
t; int
i,
n; // must use locals in checks
if (
e != null)
return
next =
e;
if (
baseIndex >=
baseLimit || (
t =
tab) == null ||
(
n =
t.length) <= (
i =
index) ||
i < 0)
return
next = null;
if ((
e =
tabAt(
t,
i)) != null &&
e.
hash < 0) {
if (
e instanceof
ForwardingNode) {
tab = ((
ForwardingNode<K,V>)
e).
nextTable;
e = null;
pushState(
t,
i,
n);
continue;
}
else if (
e instanceof
TreeBin)
e = ((
TreeBin<K,V>)
e).
first;
else
e = null;
}
if (
stack != null)
recoverState(
n);
else if ((
index =
i +
baseSize) >=
n)
index = ++
baseIndex; // visit upper slots if present
}
}
/**
* Saves traversal state upon encountering a forwarding node.
*/
private void
pushState(
Node<K,V>[]
t, int
i, int
n) {
TableStack<K,V>
s =
spare; // reuse if possible
if (
s != null)
spare =
s.
next;
else
s = new
TableStack<K,V>();
s.
tab =
t;
s.
length =
n;
s.
index =
i;
s.
next =
stack;
stack =
s;
}
/**
* Possibly pops traversal state.
*
* @param n length of current table
*/
private void
recoverState(int
n) {
TableStack<K,V>
s; int
len;
while ((
s =
stack) != null && (
index += (
len =
s.
length)) >=
n) {
n =
len;
index =
s.
index;
tab =
s.
tab;
s.
tab = null;
TableStack<K,V>
next =
s.
next;
s.
next =
spare; // save for reuse
stack =
next;
spare =
s;
}
if (
s == null && (
index +=
baseSize) >=
n)
index = ++
baseIndex;
}
}
/**
* Base of key, value, and entry Iterators. Adds fields to
* Traverser to support iterator.remove.
*/
static class
BaseIterator<K,V> extends
Traverser<K,V> {
final
ConcurrentHashMap<K,V>
map;
Node<K,V>
lastReturned;
BaseIterator(
Node<K,V>[]
tab, int
size, int
index, int
limit,
ConcurrentHashMap<K,V>
map) {
super(
tab,
size,
index,
limit);
this.
map =
map;
advance();
}
public final boolean
hasNext() { return
next != null; }
public final boolean
hasMoreElements() { return
next != null; }
public final void
remove() {
Node<K,V>
p;
if ((
p =
lastReturned) == null)
throw new
IllegalStateException();
lastReturned = null;
map.
replaceNode(
p.
key, null, null);
}
}
static final class
KeyIterator<K,V> extends
BaseIterator<K,V>
implements
Iterator<K>,
Enumeration<K> {
KeyIterator(
Node<K,V>[]
tab, int
index, int
size, int
limit,
ConcurrentHashMap<K,V>
map) {
super(
tab,
index,
size,
limit,
map);
}
public final K
next() {
Node<K,V>
p;
if ((
p =
next) == null)
throw new
NoSuchElementException();
K
k =
p.
key;
lastReturned =
p;
advance();
return
k;
}
public final K
nextElement() { return
next(); }
}
static final class
ValueIterator<K,V> extends
BaseIterator<K,V>
implements
Iterator<V>,
Enumeration<V> {
ValueIterator(
Node<K,V>[]
tab, int
index, int
size, int
limit,
ConcurrentHashMap<K,V>
map) {
super(
tab,
index,
size,
limit,
map);
}
public final V
next() {
Node<K,V>
p;
if ((
p =
next) == null)
throw new
NoSuchElementException();
V
v =
p.
val;
lastReturned =
p;
advance();
return
v;
}
public final V
nextElement() { return
next(); }
}
static final class
EntryIterator<K,V> extends
BaseIterator<K,V>
implements
Iterator<
Map.
Entry<K,V>> {
EntryIterator(
Node<K,V>[]
tab, int
index, int
size, int
limit,
ConcurrentHashMap<K,V>
map) {
super(
tab,
index,
size,
limit,
map);
}
public final
Map.
Entry<K,V>
next() {
Node<K,V>
p;
if ((
p =
next) == null)
throw new
NoSuchElementException();
K
k =
p.
key;
V
v =
p.
val;
lastReturned =
p;
advance();
return new
MapEntry<K,V>(
k,
v,
map);
}
}
/**
* Exported Entry for EntryIterator
*/
static final class
MapEntry<K,V> implements
Map.
Entry<K,V> {
final K
key; // non-null
V
val; // non-null
final
ConcurrentHashMap<K,V>
map;
MapEntry(K
key, V
val,
ConcurrentHashMap<K,V>
map) {
this.
key =
key;
this.
val =
val;
this.
map =
map;
}
public K
getKey() { return
key; }
public V
getValue() { return
val; }
public int
hashCode() { return
key.
hashCode() ^
val.
hashCode(); }
public
String toString() { return
key + "=" +
val; }
public boolean
equals(
Object o) {
Object k,
v;
Map.
Entry<?,?>
e;
return ((
o instanceof
Map.
Entry) &&
(
k = (
e = (
Map.
Entry<?,?>)
o).
getKey()) != null &&
(
v =
e.
getValue()) != null &&
(
k ==
key ||
k.
equals(
key)) &&
(
v ==
val ||
v.
equals(
val)));
}
/**
* Sets our entry's value and writes through to the map. The
* value to return is somewhat arbitrary here. Since we do not
* necessarily track asynchronous changes, the most recent
* "previous" value could be different from what we return (or
* could even have been removed, in which case the put will
* re-establish). We do not and cannot guarantee more.
*/
public V
setValue(V
value) {
if (
value == null) throw new
NullPointerException();
V
v =
val;
val =
value;
map.
put(
key,
value);
return
v;
}
}
static final class
KeySpliterator<K,V> extends
Traverser<K,V>
implements
Spliterator<K> {
long
est; // size estimate
KeySpliterator(
Node<K,V>[]
tab, int
size, int
index, int
limit,
long
est) {
super(
tab,
size,
index,
limit);
this.
est =
est;
}
public
Spliterator<K>
trySplit() {
int
i,
f,
h;
return (
h = ((
i =
baseIndex) + (
f =
baseLimit)) >>> 1) <=
i ? null :
new
KeySpliterator<K,V>(
tab,
baseSize,
baseLimit =
h,
f,
est >>>= 1);
}
public void
forEachRemaining(
Consumer<? super K>
action) {
if (
action == null) throw new
NullPointerException();
for (
Node<K,V>
p; (
p =
advance()) != null;)
action.
accept(
p.
key);
}
public boolean
tryAdvance(
Consumer<? super K>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>
p;
if ((
p =
advance()) == null)
return false;
action.
accept(
p.
key);
return true;
}
public long
estimateSize() { return
est; }
public int
characteristics() {
return
Spliterator.
DISTINCT |
Spliterator.
CONCURRENT |
Spliterator.
NONNULL;
}
}
static final class
ValueSpliterator<K,V> extends
Traverser<K,V>
implements
Spliterator<V> {
long
est; // size estimate
ValueSpliterator(
Node<K,V>[]
tab, int
size, int
index, int
limit,
long
est) {
super(
tab,
size,
index,
limit);
this.
est =
est;
}
public
Spliterator<V>
trySplit() {
int
i,
f,
h;
return (
h = ((
i =
baseIndex) + (
f =
baseLimit)) >>> 1) <=
i ? null :
new
ValueSpliterator<K,V>(
tab,
baseSize,
baseLimit =
h,
f,
est >>>= 1);
}
public void
forEachRemaining(
Consumer<? super V>
action) {
if (
action == null) throw new
NullPointerException();
for (
Node<K,V>
p; (
p =
advance()) != null;)
action.
accept(
p.
val);
}
public boolean
tryAdvance(
Consumer<? super V>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>
p;
if ((
p =
advance()) == null)
return false;
action.
accept(
p.
val);
return true;
}
public long
estimateSize() { return
est; }
public int
characteristics() {
return
Spliterator.
CONCURRENT |
Spliterator.
NONNULL;
}
}
static final class
EntrySpliterator<K,V> extends
Traverser<K,V>
implements
Spliterator<
Map.
Entry<K,V>> {
final
ConcurrentHashMap<K,V>
map; // To export MapEntry
long
est; // size estimate
EntrySpliterator(
Node<K,V>[]
tab, int
size, int
index, int
limit,
long
est,
ConcurrentHashMap<K,V>
map) {
super(
tab,
size,
index,
limit);
this.
map =
map;
this.
est =
est;
}
public
Spliterator<
Map.
Entry<K,V>>
trySplit() {
int
i,
f,
h;
return (
h = ((
i =
baseIndex) + (
f =
baseLimit)) >>> 1) <=
i ? null :
new
EntrySpliterator<K,V>(
tab,
baseSize,
baseLimit =
h,
f,
est >>>= 1,
map);
}
public void
forEachRemaining(
Consumer<? super
Map.
Entry<K,V>>
action) {
if (
action == null) throw new
NullPointerException();
for (
Node<K,V>
p; (
p =
advance()) != null; )
action.
accept(new
MapEntry<K,V>(
p.
key,
p.
val,
map));
}
public boolean
tryAdvance(
Consumer<? super
Map.
Entry<K,V>>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>
p;
if ((
p =
advance()) == null)
return false;
action.
accept(new
MapEntry<K,V>(
p.
key,
p.
val,
map));
return true;
}
public long
estimateSize() { return
est; }
public int
characteristics() {
return
Spliterator.
DISTINCT |
Spliterator.
CONCURRENT |
Spliterator.
NONNULL;
}
}
// Parallel bulk operations
/**
* Computes initial batch value for bulk tasks. The returned value
* is approximately exp2 of the number of times (minus one) to
* split task by two before executing leaf action. This value is
* faster to compute and more convenient to use as a guide to
* splitting than is the depth, since it is used while dividing by
* two anyway.
*/
final int
batchFor(long
b) {
long
n;
if (
b ==
Long.
MAX_VALUE || (
n =
sumCount()) <= 1L ||
n <
b)
return 0;
int
sp =
ForkJoinPool.
getCommonPoolParallelism() << 2; // slack of 4
return (
b <= 0L || (
n /=
b) >=
sp) ?
sp : (int)
n;
}
/**
* Performs the given action for each (key, value).
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void
forEach(long
parallelismThreshold,
BiConsumer<? super K,? super V>
action) {
if (
action == null) throw new
NullPointerException();
new
ForEachMappingTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
action).
invoke();
}
/**
* Performs the given action for each non-null transformation
* of each (key, value).
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @param <U> the return type of the transformer
* @since 1.8
*/
public <U> void
forEach(long
parallelismThreshold,
BiFunction<? super K, ? super V, ? extends U>
transformer,
Consumer<? super U>
action) {
if (
transformer == null ||
action == null)
throw new
NullPointerException();
new
ForEachTransformedMappingTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
transformer,
action).
invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each (key, value), or null if none. Upon
* success, further element processing is suppressed and the
* results of any other parallel invocations of the search
* function are ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @param <U> the return type of the search function
* @return a non-null result from applying the given search
* function on each (key, value), or null if none
* @since 1.8
*/
public <U> U
search(long
parallelismThreshold,
BiFunction<? super K, ? super V, ? extends U>
searchFunction) {
if (
searchFunction == null) throw new
NullPointerException();
return new
SearchMappingsTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
searchFunction, new
AtomicReference<U>()).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @param <U> the return type of the transformer
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public <U> U
reduce(long
parallelismThreshold,
BiFunction<? super K, ? super V, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceMappingsTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public double
reduceToDouble(long
parallelismThreshold,
ToDoubleBiFunction<? super K, ? super V>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceMappingsToDoubleTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public long
reduceToLong(long
parallelismThreshold,
ToLongBiFunction<? super K, ? super V>
transformer,
long
basis,
LongBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceMappingsToLongTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all (key, value) pairs using the given reducer to
* combine values, and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all (key, value) pairs
* @since 1.8
*/
public int
reduceToInt(long
parallelismThreshold,
ToIntBiFunction<? super K, ? super V>
transformer,
int
basis,
IntBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceMappingsToIntTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Performs the given action for each key.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void
forEachKey(long
parallelismThreshold,
Consumer<? super K>
action) {
if (
action == null) throw new
NullPointerException();
new
ForEachKeyTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
action).
invoke();
}
/**
* Performs the given action for each non-null transformation
* of each key.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @param <U> the return type of the transformer
* @since 1.8
*/
public <U> void
forEachKey(long
parallelismThreshold,
Function<? super K, ? extends U>
transformer,
Consumer<? super U>
action) {
if (
transformer == null ||
action == null)
throw new
NullPointerException();
new
ForEachTransformedKeyTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
transformer,
action).
invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each key, or null if none. Upon success,
* further element processing is suppressed and the results of
* any other parallel invocations of the search function are
* ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @param <U> the return type of the search function
* @return a non-null result from applying the given search
* function on each key, or null if none
* @since 1.8
*/
public <U> U
searchKeys(long
parallelismThreshold,
Function<? super K, ? extends U>
searchFunction) {
if (
searchFunction == null) throw new
NullPointerException();
return new
SearchKeysTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
searchFunction, new
AtomicReference<U>()).
invoke();
}
/**
* Returns the result of accumulating all keys using the given
* reducer to combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param reducer a commutative associative combining function
* @return the result of accumulating all keys using the given
* reducer to combine values, or null if none
* @since 1.8
*/
public K
reduceKeys(long
parallelismThreshold,
BiFunction<? super K, ? super K, ? extends K>
reducer) {
if (
reducer == null) throw new
NullPointerException();
return new
ReduceKeysTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, or
* null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @param <U> the return type of the transformer
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public <U> U
reduceKeys(long
parallelismThreshold,
Function<? super K, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceKeysTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, and
* the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public double
reduceKeysToDouble(long
parallelismThreshold,
ToDoubleFunction<? super K>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceKeysToDoubleTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, and
* the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public long
reduceKeysToLong(long
parallelismThreshold,
ToLongFunction<? super K>
transformer,
long
basis,
LongBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceKeysToLongTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all keys using the given reducer to combine values, and
* the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all keys
* @since 1.8
*/
public int
reduceKeysToInt(long
parallelismThreshold,
ToIntFunction<? super K>
transformer,
int
basis,
IntBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceKeysToIntTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Performs the given action for each value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void
forEachValue(long
parallelismThreshold,
Consumer<? super V>
action) {
if (
action == null)
throw new
NullPointerException();
new
ForEachValueTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
action).
invoke();
}
/**
* Performs the given action for each non-null transformation
* of each value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @param <U> the return type of the transformer
* @since 1.8
*/
public <U> void
forEachValue(long
parallelismThreshold,
Function<? super V, ? extends U>
transformer,
Consumer<? super U>
action) {
if (
transformer == null ||
action == null)
throw new
NullPointerException();
new
ForEachTransformedValueTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
transformer,
action).
invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each value, or null if none. Upon success,
* further element processing is suppressed and the results of
* any other parallel invocations of the search function are
* ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @param <U> the return type of the search function
* @return a non-null result from applying the given search
* function on each value, or null if none
* @since 1.8
*/
public <U> U
searchValues(long
parallelismThreshold,
Function<? super V, ? extends U>
searchFunction) {
if (
searchFunction == null) throw new
NullPointerException();
return new
SearchValuesTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
searchFunction, new
AtomicReference<U>()).
invoke();
}
/**
* Returns the result of accumulating all values using the
* given reducer to combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param reducer a commutative associative combining function
* @return the result of accumulating all values
* @since 1.8
*/
public V
reduceValues(long
parallelismThreshold,
BiFunction<? super V, ? super V, ? extends V>
reducer) {
if (
reducer == null) throw new
NullPointerException();
return new
ReduceValuesTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values, or
* null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @param <U> the return type of the transformer
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public <U> U
reduceValues(long
parallelismThreshold,
Function<? super V, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceValuesTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public double
reduceValuesToDouble(long
parallelismThreshold,
ToDoubleFunction<? super V>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceValuesToDoubleTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public long
reduceValuesToLong(long
parallelismThreshold,
ToLongFunction<? super V>
transformer,
long
basis,
LongBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceValuesToLongTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all values using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all values
* @since 1.8
*/
public int
reduceValuesToInt(long
parallelismThreshold,
ToIntFunction<? super V>
transformer,
int
basis,
IntBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceValuesToIntTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Performs the given action for each entry.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param action the action
* @since 1.8
*/
public void
forEachEntry(long
parallelismThreshold,
Consumer<? super
Map.
Entry<K,V>>
action) {
if (
action == null) throw new
NullPointerException();
new
ForEachEntryTask<K,V>(null,
batchFor(
parallelismThreshold), 0, 0,
table,
action).
invoke();
}
/**
* Performs the given action for each non-null transformation
* of each entry.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case the action is not applied)
* @param action the action
* @param <U> the return type of the transformer
* @since 1.8
*/
public <U> void
forEachEntry(long
parallelismThreshold,
Function<
Map.
Entry<K,V>, ? extends U>
transformer,
Consumer<? super U>
action) {
if (
transformer == null ||
action == null)
throw new
NullPointerException();
new
ForEachTransformedEntryTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
transformer,
action).
invoke();
}
/**
* Returns a non-null result from applying the given search
* function on each entry, or null if none. Upon success,
* further element processing is suppressed and the results of
* any other parallel invocations of the search function are
* ignored.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param searchFunction a function returning a non-null
* result on success, else null
* @param <U> the return type of the search function
* @return a non-null result from applying the given search
* function on each entry, or null if none
* @since 1.8
*/
public <U> U
searchEntries(long
parallelismThreshold,
Function<
Map.
Entry<K,V>, ? extends U>
searchFunction) {
if (
searchFunction == null) throw new
NullPointerException();
return new
SearchEntriesTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
searchFunction, new
AtomicReference<U>()).
invoke();
}
/**
* Returns the result of accumulating all entries using the
* given reducer to combine values, or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param reducer a commutative associative combining function
* @return the result of accumulating all entries
* @since 1.8
*/
public
Map.
Entry<K,V>
reduceEntries(long
parallelismThreshold,
BiFunction<
Map.
Entry<K,V>,
Map.
Entry<K,V>, ? extends
Map.
Entry<K,V>>
reducer) {
if (
reducer == null) throw new
NullPointerException();
return new
ReduceEntriesTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* or null if none.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element, or null if there is no transformation (in
* which case it is not combined)
* @param reducer a commutative associative combining function
* @param <U> the return type of the transformer
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public <U> U
reduceEntries(long
parallelismThreshold,
Function<
Map.
Entry<K,V>, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceEntriesTask<K,V,U>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public double
reduceEntriesToDouble(long
parallelismThreshold,
ToDoubleFunction<
Map.
Entry<K,V>>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceEntriesToDoubleTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public long
reduceEntriesToLong(long
parallelismThreshold,
ToLongFunction<
Map.
Entry<K,V>>
transformer,
long
basis,
LongBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceEntriesToLongTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/**
* Returns the result of accumulating the given transformation
* of all entries using the given reducer to combine values,
* and the given basis as an identity value.
*
* @param parallelismThreshold the (estimated) number of elements
* needed for this operation to be executed in parallel
* @param transformer a function returning the transformation
* for an element
* @param basis the identity (initial default value) for the reduction
* @param reducer a commutative associative combining function
* @return the result of accumulating the given transformation
* of all entries
* @since 1.8
*/
public int
reduceEntriesToInt(long
parallelismThreshold,
ToIntFunction<
Map.
Entry<K,V>>
transformer,
int
basis,
IntBinaryOperator reducer) {
if (
transformer == null ||
reducer == null)
throw new
NullPointerException();
return new
MapReduceEntriesToIntTask<K,V>
(null,
batchFor(
parallelismThreshold), 0, 0,
table,
null,
transformer,
basis,
reducer).
invoke();
}
/* ----------------Views -------------- */
/**
* Base class for views.
*/
abstract static class
CollectionView<K,V,E>
implements
Collection<E>, java.io.
Serializable {
private static final long
serialVersionUID = 7249069246763182397L;
final
ConcurrentHashMap<K,V>
map;
CollectionView(
ConcurrentHashMap<K,V>
map) { this.
map =
map; }
/**
* Returns the map backing this view.
*
* @return the map backing this view
*/
public
ConcurrentHashMap<K,V>
getMap() { return
map; }
/**
* Removes all of the elements from this view, by removing all
* the mappings from the map backing this view.
*/
public final void
clear() {
map.
clear(); }
public final int
size() { return
map.
size(); }
public final boolean
isEmpty() { return
map.
isEmpty(); }
// implementations below rely on concrete classes supplying these
// abstract methods
/**
* Returns an iterator over the elements in this collection.
*
* <p>The returned iterator is
* <a href="package-summary.html#Weakly"><i>weakly consistent</i></a>.
*
* @return an iterator over the elements in this collection
*/
public abstract
Iterator<E>
iterator();
public abstract boolean
contains(
Object o);
public abstract boolean
remove(
Object o);
private static final
String oomeMsg = "Required array size too large";
public final
Object[]
toArray() {
long
sz =
map.
mappingCount();
if (
sz >
MAX_ARRAY_SIZE)
throw new
OutOfMemoryError(
oomeMsg);
int
n = (int)
sz;
Object[]
r = new
Object[
n];
int
i = 0;
for (E
e : this) {
if (
i ==
n) {
if (
n >=
MAX_ARRAY_SIZE)
throw new
OutOfMemoryError(
oomeMsg);
if (
n >=
MAX_ARRAY_SIZE - (
MAX_ARRAY_SIZE >>> 1) - 1)
n =
MAX_ARRAY_SIZE;
else
n += (
n >>> 1) + 1;
r =
Arrays.
copyOf(
r,
n);
}
r[
i++] =
e;
}
return (
i ==
n) ?
r :
Arrays.
copyOf(
r,
i);
}
@
SuppressWarnings("unchecked")
public final <T> T[]
toArray(T[]
a) {
long
sz =
map.
mappingCount();
if (
sz >
MAX_ARRAY_SIZE)
throw new
OutOfMemoryError(
oomeMsg);
int
m = (int)
sz;
T[]
r = (
a.length >=
m) ?
a :
(T[])java.lang.reflect.
Array
.
newInstance(
a.
getClass().
getComponentType(),
m);
int
n =
r.length;
int
i = 0;
for (E
e : this) {
if (
i ==
n) {
if (
n >=
MAX_ARRAY_SIZE)
throw new
OutOfMemoryError(
oomeMsg);
if (
n >=
MAX_ARRAY_SIZE - (
MAX_ARRAY_SIZE >>> 1) - 1)
n =
MAX_ARRAY_SIZE;
else
n += (
n >>> 1) + 1;
r =
Arrays.
copyOf(
r,
n);
}
r[
i++] = (T)
e;
}
if (
a ==
r &&
i <
n) {
r[
i] = null; // null-terminate
return
r;
}
return (
i ==
n) ?
r :
Arrays.
copyOf(
r,
i);
}
/**
* Returns a string representation of this collection.
* The string representation consists of the string representations
* of the collection's elements in the order they are returned by
* its iterator, enclosed in square brackets ({@code "[]"}).
* Adjacent elements are separated by the characters {@code ", "}
* (comma and space). Elements are converted to strings as by
* {@link String#valueOf(Object)}.
*
* @return a string representation of this collection
*/
public final
String toString() {
StringBuilder sb = new
StringBuilder();
sb.
append('[');
Iterator<E>
it =
iterator();
if (
it.
hasNext()) {
for (;;) {
Object e =
it.
next();
sb.
append(
e == this ? "(this Collection)" :
e);
if (!
it.
hasNext())
break;
sb.
append(',').
append(' ');
}
}
return
sb.
append(']').
toString();
}
public final boolean
containsAll(
Collection<?>
c) {
if (
c != this) {
for (
Object e :
c) {
if (
e == null || !
contains(
e))
return false;
}
}
return true;
}
public final boolean
removeAll(
Collection<?>
c) {
if (
c == null) throw new
NullPointerException();
boolean
modified = false;
for (
Iterator<E>
it =
iterator();
it.
hasNext();) {
if (
c.
contains(
it.
next())) {
it.
remove();
modified = true;
}
}
return
modified;
}
public final boolean
retainAll(
Collection<?>
c) {
if (
c == null) throw new
NullPointerException();
boolean
modified = false;
for (
Iterator<E>
it =
iterator();
it.
hasNext();) {
if (!
c.
contains(
it.
next())) {
it.
remove();
modified = true;
}
}
return
modified;
}
}
/**
* A view of a ConcurrentHashMap as a {@link Set} of keys, in
* which additions may optionally be enabled by mapping to a
* common value. This class cannot be directly instantiated.
* See {@link #keySet() keySet()},
* {@link #keySet(Object) keySet(V)},
* {@link #newKeySet() newKeySet()},
* {@link #newKeySet(int) newKeySet(int)}.
*
* @since 1.8
*/
public static class
KeySetView<K,V> extends
CollectionView<K,V,K>
implements
Set<K>, java.io.
Serializable {
private static final long
serialVersionUID = 7249069246763182397L;
private final V
value;
KeySetView(
ConcurrentHashMap<K,V>
map, V
value) { // non-public
super(
map);
this.
value =
value;
}
/**
* Returns the default mapped value for additions,
* or {@code null} if additions are not supported.
*
* @return the default mapped value for additions, or {@code null}
* if not supported
*/
public V
getMappedValue() { return
value; }
/**
* {@inheritDoc}
* @throws NullPointerException if the specified key is null
*/
public boolean
contains(
Object o) { return
map.
containsKey(
o); }
/**
* Removes the key from this map view, by removing the key (and its
* corresponding value) from the backing map. This method does
* nothing if the key is not in the map.
*
* @param o the key to be removed from the backing map
* @return {@code true} if the backing map contained the specified key
* @throws NullPointerException if the specified key is null
*/
public boolean
remove(
Object o) { return
map.
remove(
o) != null; }
/**
* @return an iterator over the keys of the backing map
*/
public
Iterator<K>
iterator() {
Node<K,V>[]
t;
ConcurrentHashMap<K,V>
m =
map;
int
f = (
t =
m.
table) == null ? 0 :
t.length;
return new
KeyIterator<K,V>(
t,
f, 0,
f,
m);
}
/**
* Adds the specified key to this set view by mapping the key to
* the default mapped value in the backing map, if defined.
*
* @param e key to be added
* @return {@code true} if this set changed as a result of the call
* @throws NullPointerException if the specified key is null
* @throws UnsupportedOperationException if no default mapped value
* for additions was provided
*/
public boolean
add(K
e) {
V
v;
if ((
v =
value) == null)
throw new
UnsupportedOperationException();
return
map.
putVal(
e,
v, true) == null;
}
/**
* Adds all of the elements in the specified collection to this set,
* as if by calling {@link #add} on each one.
*
* @param c the elements to be inserted into this set
* @return {@code true} if this set changed as a result of the call
* @throws NullPointerException if the collection or any of its
* elements are {@code null}
* @throws UnsupportedOperationException if no default mapped value
* for additions was provided
*/
public boolean
addAll(
Collection<? extends K>
c) {
boolean
added = false;
V
v;
if ((
v =
value) == null)
throw new
UnsupportedOperationException();
for (K
e :
c) {
if (
map.
putVal(
e,
v, true) == null)
added = true;
}
return
added;
}
public int
hashCode() {
int
h = 0;
for (K
e : this)
h +=
e.
hashCode();
return
h;
}
public boolean
equals(
Object o) {
Set<?>
c;
return ((
o instanceof
Set) &&
((
c = (
Set<?>)
o) == this ||
(
containsAll(
c) &&
c.
containsAll(this))));
}
public
Spliterator<K>
spliterator() {
Node<K,V>[]
t;
ConcurrentHashMap<K,V>
m =
map;
long
n =
m.
sumCount();
int
f = (
t =
m.
table) == null ? 0 :
t.length;
return new
KeySpliterator<K,V>(
t,
f, 0,
f,
n < 0L ? 0L :
n);
}
public void
forEach(
Consumer<? super K>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>[]
t;
if ((
t =
map.
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; )
action.
accept(
p.
key);
}
}
}
/**
* A view of a ConcurrentHashMap as a {@link Collection} of
* values, in which additions are disabled. This class cannot be
* directly instantiated. See {@link #values()}.
*/
static final class
ValuesView<K,V> extends
CollectionView<K,V,V>
implements
Collection<V>, java.io.
Serializable {
private static final long
serialVersionUID = 2249069246763182397L;
ValuesView(
ConcurrentHashMap<K,V>
map) { super(
map); }
public final boolean
contains(
Object o) {
return
map.
containsValue(
o);
}
public final boolean
remove(
Object o) {
if (
o != null) {
for (
Iterator<V>
it =
iterator();
it.
hasNext();) {
if (
o.
equals(
it.
next())) {
it.
remove();
return true;
}
}
}
return false;
}
public final
Iterator<V>
iterator() {
ConcurrentHashMap<K,V>
m =
map;
Node<K,V>[]
t;
int
f = (
t =
m.
table) == null ? 0 :
t.length;
return new
ValueIterator<K,V>(
t,
f, 0,
f,
m);
}
public final boolean
add(V
e) {
throw new
UnsupportedOperationException();
}
public final boolean
addAll(
Collection<? extends V>
c) {
throw new
UnsupportedOperationException();
}
public
Spliterator<V>
spliterator() {
Node<K,V>[]
t;
ConcurrentHashMap<K,V>
m =
map;
long
n =
m.
sumCount();
int
f = (
t =
m.
table) == null ? 0 :
t.length;
return new
ValueSpliterator<K,V>(
t,
f, 0,
f,
n < 0L ? 0L :
n);
}
public void
forEach(
Consumer<? super V>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>[]
t;
if ((
t =
map.
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; )
action.
accept(
p.
val);
}
}
}
/**
* A view of a ConcurrentHashMap as a {@link Set} of (key, value)
* entries. This class cannot be directly instantiated. See
* {@link #entrySet()}.
*/
static final class
EntrySetView<K,V> extends
CollectionView<K,V,
Map.
Entry<K,V>>
implements
Set<
Map.
Entry<K,V>>, java.io.
Serializable {
private static final long
serialVersionUID = 2249069246763182397L;
EntrySetView(
ConcurrentHashMap<K,V>
map) { super(
map); }
public boolean
contains(
Object o) {
Object k,
v,
r;
Map.
Entry<?,?>
e;
return ((
o instanceof
Map.
Entry) &&
(
k = (
e = (
Map.
Entry<?,?>)
o).
getKey()) != null &&
(
r =
map.
get(
k)) != null &&
(
v =
e.
getValue()) != null &&
(
v ==
r ||
v.
equals(
r)));
}
public boolean
remove(
Object o) {
Object k,
v;
Map.
Entry<?,?>
e;
return ((
o instanceof
Map.
Entry) &&
(
k = (
e = (
Map.
Entry<?,?>)
o).
getKey()) != null &&
(
v =
e.
getValue()) != null &&
map.
remove(
k,
v));
}
/**
* @return an iterator over the entries of the backing map
*/
public
Iterator<
Map.
Entry<K,V>>
iterator() {
ConcurrentHashMap<K,V>
m =
map;
Node<K,V>[]
t;
int
f = (
t =
m.
table) == null ? 0 :
t.length;
return new
EntryIterator<K,V>(
t,
f, 0,
f,
m);
}
public boolean
add(
Entry<K,V>
e) {
return
map.
putVal(
e.
getKey(),
e.
getValue(), false) == null;
}
public boolean
addAll(
Collection<? extends
Entry<K,V>>
c) {
boolean
added = false;
for (
Entry<K,V>
e :
c) {
if (
add(
e))
added = true;
}
return
added;
}
public final int
hashCode() {
int
h = 0;
Node<K,V>[]
t;
if ((
t =
map.
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; ) {
h +=
p.
hashCode();
}
}
return
h;
}
public final boolean
equals(
Object o) {
Set<?>
c;
return ((
o instanceof
Set) &&
((
c = (
Set<?>)
o) == this ||
(
containsAll(
c) &&
c.
containsAll(this))));
}
public
Spliterator<
Map.
Entry<K,V>>
spliterator() {
Node<K,V>[]
t;
ConcurrentHashMap<K,V>
m =
map;
long
n =
m.
sumCount();
int
f = (
t =
m.
table) == null ? 0 :
t.length;
return new
EntrySpliterator<K,V>(
t,
f, 0,
f,
n < 0L ? 0L :
n,
m);
}
public void
forEach(
Consumer<? super
Map.
Entry<K,V>>
action) {
if (
action == null) throw new
NullPointerException();
Node<K,V>[]
t;
if ((
t =
map.
table) != null) {
Traverser<K,V>
it = new
Traverser<K,V>(
t,
t.length, 0,
t.length);
for (
Node<K,V>
p; (
p =
it.
advance()) != null; )
action.
accept(new
MapEntry<K,V>(
p.
key,
p.
val,
map));
}
}
}
// -------------------------------------------------------
/**
* Base class for bulk tasks. Repeats some fields and code from
* class Traverser, because we need to subclass CountedCompleter.
*/
@
SuppressWarnings("serial")
abstract static class
BulkTask<K,V,R> extends
CountedCompleter<R> {
Node<K,V>[]
tab; // same as Traverser
Node<K,V>
next;
TableStack<K,V>
stack,
spare;
int
index;
int
baseIndex;
int
baseLimit;
final int
baseSize;
int
batch; // split control
BulkTask(
BulkTask<K,V,?>
par, int
b, int
i, int
f,
Node<K,V>[]
t) {
super(
par);
this.
batch =
b;
this.
index = this.
baseIndex =
i;
if ((this.
tab =
t) == null)
this.
baseSize = this.
baseLimit = 0;
else if (
par == null)
this.
baseSize = this.
baseLimit =
t.length;
else {
this.
baseLimit =
f;
this.
baseSize =
par.
baseSize;
}
}
/**
* Same as Traverser version
*/
final
Node<K,V>
advance() {
Node<K,V>
e;
if ((
e =
next) != null)
e =
e.
next;
for (;;) {
Node<K,V>[]
t; int
i,
n;
if (
e != null)
return
next =
e;
if (
baseIndex >=
baseLimit || (
t =
tab) == null ||
(
n =
t.length) <= (
i =
index) ||
i < 0)
return
next = null;
if ((
e =
tabAt(
t,
i)) != null &&
e.
hash < 0) {
if (
e instanceof
ForwardingNode) {
tab = ((
ForwardingNode<K,V>)
e).
nextTable;
e = null;
pushState(
t,
i,
n);
continue;
}
else if (
e instanceof
TreeBin)
e = ((
TreeBin<K,V>)
e).
first;
else
e = null;
}
if (
stack != null)
recoverState(
n);
else if ((
index =
i +
baseSize) >=
n)
index = ++
baseIndex;
}
}
private void
pushState(
Node<K,V>[]
t, int
i, int
n) {
TableStack<K,V>
s =
spare;
if (
s != null)
spare =
s.
next;
else
s = new
TableStack<K,V>();
s.
tab =
t;
s.
length =
n;
s.
index =
i;
s.
next =
stack;
stack =
s;
}
private void
recoverState(int
n) {
TableStack<K,V>
s; int
len;
while ((
s =
stack) != null && (
index += (
len =
s.
length)) >=
n) {
n =
len;
index =
s.
index;
tab =
s.
tab;
s.
tab = null;
TableStack<K,V>
next =
s.
next;
s.
next =
spare; // save for reuse
stack =
next;
spare =
s;
}
if (
s == null && (
index +=
baseSize) >=
n)
index = ++
baseIndex;
}
}
/*
* Task classes. Coded in a regular but ugly format/style to
* simplify checks that each variant differs in the right way from
* others. The null screenings exist because compilers cannot tell
* that we've already null-checked task arguments, so we force
* simplest hoisted bypass to help avoid convoluted traps.
*/
@
SuppressWarnings("serial")
static final class
ForEachKeyTask<K,V>
extends
BulkTask<K,V,
Void> {
final
Consumer<? super K>
action;
ForEachKeyTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Consumer<? super K>
action) {
super(
p,
b,
i,
f,
t);
this.
action =
action;
}
public final void
compute() {
final
Consumer<? super K>
action;
if ((
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachKeyTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null;)
action.
accept(
p.
key);
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachValueTask<K,V>
extends
BulkTask<K,V,
Void> {
final
Consumer<? super V>
action;
ForEachValueTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Consumer<? super V>
action) {
super(
p,
b,
i,
f,
t);
this.
action =
action;
}
public final void
compute() {
final
Consumer<? super V>
action;
if ((
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachValueTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null;)
action.
accept(
p.
val);
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachEntryTask<K,V>
extends
BulkTask<K,V,
Void> {
final
Consumer<? super
Entry<K,V>>
action;
ForEachEntryTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Consumer<? super
Entry<K,V>>
action) {
super(
p,
b,
i,
f,
t);
this.
action =
action;
}
public final void
compute() {
final
Consumer<? super
Entry<K,V>>
action;
if ((
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachEntryTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
action.
accept(
p);
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachMappingTask<K,V>
extends
BulkTask<K,V,
Void> {
final
BiConsumer<? super K, ? super V>
action;
ForEachMappingTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
BiConsumer<? super K,? super V>
action) {
super(
p,
b,
i,
f,
t);
this.
action =
action;
}
public final void
compute() {
final
BiConsumer<? super K, ? super V>
action;
if ((
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachMappingTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
action.
accept(
p.
key,
p.
val);
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachTransformedKeyTask<K,V,U>
extends
BulkTask<K,V,
Void> {
final
Function<? super K, ? extends U>
transformer;
final
Consumer<? super U>
action;
ForEachTransformedKeyTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Function<? super K, ? extends U>
transformer,
Consumer<? super U>
action) {
super(
p,
b,
i,
f,
t);
this.
transformer =
transformer; this.
action =
action;
}
public final void
compute() {
final
Function<? super K, ? extends U>
transformer;
final
Consumer<? super U>
action;
if ((
transformer = this.
transformer) != null &&
(
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachTransformedKeyTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
transformer,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p.
key)) != null)
action.
accept(
u);
}
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachTransformedValueTask<K,V,U>
extends
BulkTask<K,V,
Void> {
final
Function<? super V, ? extends U>
transformer;
final
Consumer<? super U>
action;
ForEachTransformedValueTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Function<? super V, ? extends U>
transformer,
Consumer<? super U>
action) {
super(
p,
b,
i,
f,
t);
this.
transformer =
transformer; this.
action =
action;
}
public final void
compute() {
final
Function<? super V, ? extends U>
transformer;
final
Consumer<? super U>
action;
if ((
transformer = this.
transformer) != null &&
(
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachTransformedValueTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
transformer,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p.
val)) != null)
action.
accept(
u);
}
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachTransformedEntryTask<K,V,U>
extends
BulkTask<K,V,
Void> {
final
Function<
Map.
Entry<K,V>, ? extends U>
transformer;
final
Consumer<? super U>
action;
ForEachTransformedEntryTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Function<
Map.
Entry<K,V>, ? extends U>
transformer,
Consumer<? super U>
action) {
super(
p,
b,
i,
f,
t);
this.
transformer =
transformer; this.
action =
action;
}
public final void
compute() {
final
Function<
Map.
Entry<K,V>, ? extends U>
transformer;
final
Consumer<? super U>
action;
if ((
transformer = this.
transformer) != null &&
(
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachTransformedEntryTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
transformer,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p)) != null)
action.
accept(
u);
}
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
ForEachTransformedMappingTask<K,V,U>
extends
BulkTask<K,V,
Void> {
final
BiFunction<? super K, ? super V, ? extends U>
transformer;
final
Consumer<? super U>
action;
ForEachTransformedMappingTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
BiFunction<? super K, ? super V, ? extends U>
transformer,
Consumer<? super U>
action) {
super(
p,
b,
i,
f,
t);
this.
transformer =
transformer; this.
action =
action;
}
public final void
compute() {
final
BiFunction<? super K, ? super V, ? extends U>
transformer;
final
Consumer<? super U>
action;
if ((
transformer = this.
transformer) != null &&
(
action = this.
action) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
new
ForEachTransformedMappingTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
transformer,
action).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p.
key,
p.
val)) != null)
action.
accept(
u);
}
propagateCompletion();
}
}
}
@
SuppressWarnings("serial")
static final class
SearchKeysTask<K,V,U>
extends
BulkTask<K,V,U> {
final
Function<? super K, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
SearchKeysTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Function<? super K, ? extends U>
searchFunction,
AtomicReference<U>
result) {
super(
p,
b,
i,
f,
t);
this.
searchFunction =
searchFunction; this.
result =
result;
}
public final U
getRawResult() { return
result.
get(); }
public final void
compute() {
final
Function<? super K, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
if ((
searchFunction = this.
searchFunction) != null &&
(
result = this.
result) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
if (
result.
get() != null)
return;
addToPendingCount(1);
new
SearchKeysTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
searchFunction,
result).
fork();
}
while (
result.
get() == null) {
U
u;
Node<K,V>
p;
if ((
p =
advance()) == null) {
propagateCompletion();
break;
}
if ((
u =
searchFunction.
apply(
p.
key)) != null) {
if (
result.
compareAndSet(null,
u))
quietlyCompleteRoot();
break;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
SearchValuesTask<K,V,U>
extends
BulkTask<K,V,U> {
final
Function<? super V, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
SearchValuesTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Function<? super V, ? extends U>
searchFunction,
AtomicReference<U>
result) {
super(
p,
b,
i,
f,
t);
this.
searchFunction =
searchFunction; this.
result =
result;
}
public final U
getRawResult() { return
result.
get(); }
public final void
compute() {
final
Function<? super V, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
if ((
searchFunction = this.
searchFunction) != null &&
(
result = this.
result) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
if (
result.
get() != null)
return;
addToPendingCount(1);
new
SearchValuesTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
searchFunction,
result).
fork();
}
while (
result.
get() == null) {
U
u;
Node<K,V>
p;
if ((
p =
advance()) == null) {
propagateCompletion();
break;
}
if ((
u =
searchFunction.
apply(
p.
val)) != null) {
if (
result.
compareAndSet(null,
u))
quietlyCompleteRoot();
break;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
SearchEntriesTask<K,V,U>
extends
BulkTask<K,V,U> {
final
Function<
Entry<K,V>, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
SearchEntriesTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
Function<
Entry<K,V>, ? extends U>
searchFunction,
AtomicReference<U>
result) {
super(
p,
b,
i,
f,
t);
this.
searchFunction =
searchFunction; this.
result =
result;
}
public final U
getRawResult() { return
result.
get(); }
public final void
compute() {
final
Function<
Entry<K,V>, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
if ((
searchFunction = this.
searchFunction) != null &&
(
result = this.
result) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
if (
result.
get() != null)
return;
addToPendingCount(1);
new
SearchEntriesTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
searchFunction,
result).
fork();
}
while (
result.
get() == null) {
U
u;
Node<K,V>
p;
if ((
p =
advance()) == null) {
propagateCompletion();
break;
}
if ((
u =
searchFunction.
apply(
p)) != null) {
if (
result.
compareAndSet(null,
u))
quietlyCompleteRoot();
return;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
SearchMappingsTask<K,V,U>
extends
BulkTask<K,V,U> {
final
BiFunction<? super K, ? super V, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
SearchMappingsTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
BiFunction<? super K, ? super V, ? extends U>
searchFunction,
AtomicReference<U>
result) {
super(
p,
b,
i,
f,
t);
this.
searchFunction =
searchFunction; this.
result =
result;
}
public final U
getRawResult() { return
result.
get(); }
public final void
compute() {
final
BiFunction<? super K, ? super V, ? extends U>
searchFunction;
final
AtomicReference<U>
result;
if ((
searchFunction = this.
searchFunction) != null &&
(
result = this.
result) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
if (
result.
get() != null)
return;
addToPendingCount(1);
new
SearchMappingsTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
searchFunction,
result).
fork();
}
while (
result.
get() == null) {
U
u;
Node<K,V>
p;
if ((
p =
advance()) == null) {
propagateCompletion();
break;
}
if ((
u =
searchFunction.
apply(
p.
key,
p.
val)) != null) {
if (
result.
compareAndSet(null,
u))
quietlyCompleteRoot();
break;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
ReduceKeysTask<K,V>
extends
BulkTask<K,V,K> {
final
BiFunction<? super K, ? super K, ? extends K>
reducer;
K
result;
ReduceKeysTask<K,V>
rights,
nextRight;
ReduceKeysTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
ReduceKeysTask<K,V>
nextRight,
BiFunction<? super K, ? super K, ? extends K>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
reducer =
reducer;
}
public final K
getRawResult() { return
result; }
public final void
compute() {
final
BiFunction<? super K, ? super K, ? extends K>
reducer;
if ((
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
ReduceKeysTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
reducer)).
fork();
}
K
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
K
u =
p.
key;
r = (
r == null) ?
u :
u == null ?
r :
reducer.
apply(
r,
u);
}
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
ReduceKeysTask<K,V>
t = (
ReduceKeysTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
K
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
ReduceValuesTask<K,V>
extends
BulkTask<K,V,V> {
final
BiFunction<? super V, ? super V, ? extends V>
reducer;
V
result;
ReduceValuesTask<K,V>
rights,
nextRight;
ReduceValuesTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
ReduceValuesTask<K,V>
nextRight,
BiFunction<? super V, ? super V, ? extends V>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
reducer =
reducer;
}
public final V
getRawResult() { return
result; }
public final void
compute() {
final
BiFunction<? super V, ? super V, ? extends V>
reducer;
if ((
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
ReduceValuesTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
reducer)).
fork();
}
V
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
V
v =
p.
val;
r = (
r == null) ?
v :
reducer.
apply(
r,
v);
}
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
ReduceValuesTask<K,V>
t = (
ReduceValuesTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
V
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
ReduceEntriesTask<K,V>
extends
BulkTask<K,V,
Map.
Entry<K,V>> {
final
BiFunction<
Map.
Entry<K,V>,
Map.
Entry<K,V>, ? extends
Map.
Entry<K,V>>
reducer;
Map.
Entry<K,V>
result;
ReduceEntriesTask<K,V>
rights,
nextRight;
ReduceEntriesTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
ReduceEntriesTask<K,V>
nextRight,
BiFunction<
Entry<K,V>,
Map.
Entry<K,V>, ? extends
Map.
Entry<K,V>>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
reducer =
reducer;
}
public final
Map.
Entry<K,V>
getRawResult() { return
result; }
public final void
compute() {
final
BiFunction<
Map.
Entry<K,V>,
Map.
Entry<K,V>, ? extends
Map.
Entry<K,V>>
reducer;
if ((
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
ReduceEntriesTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
reducer)).
fork();
}
Map.
Entry<K,V>
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; )
r = (
r == null) ?
p :
reducer.
apply(
r,
p);
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
ReduceEntriesTask<K,V>
t = (
ReduceEntriesTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
Map.
Entry<K,V>
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceKeysTask<K,V,U>
extends
BulkTask<K,V,U> {
final
Function<? super K, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
U
result;
MapReduceKeysTask<K,V,U>
rights,
nextRight;
MapReduceKeysTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceKeysTask<K,V,U>
nextRight,
Function<? super K, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
reducer =
reducer;
}
public final U
getRawResult() { return
result; }
public final void
compute() {
final
Function<? super K, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceKeysTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
reducer)).
fork();
}
U
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p.
key)) != null)
r = (
r == null) ?
u :
reducer.
apply(
r,
u);
}
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceKeysTask<K,V,U>
t = (
MapReduceKeysTask<K,V,U>)
c,
s =
t.
rights;
while (
s != null) {
U
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceValuesTask<K,V,U>
extends
BulkTask<K,V,U> {
final
Function<? super V, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
U
result;
MapReduceValuesTask<K,V,U>
rights,
nextRight;
MapReduceValuesTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceValuesTask<K,V,U>
nextRight,
Function<? super V, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
reducer =
reducer;
}
public final U
getRawResult() { return
result; }
public final void
compute() {
final
Function<? super V, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceValuesTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
reducer)).
fork();
}
U
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p.
val)) != null)
r = (
r == null) ?
u :
reducer.
apply(
r,
u);
}
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceValuesTask<K,V,U>
t = (
MapReduceValuesTask<K,V,U>)
c,
s =
t.
rights;
while (
s != null) {
U
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceEntriesTask<K,V,U>
extends
BulkTask<K,V,U> {
final
Function<
Map.
Entry<K,V>, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
U
result;
MapReduceEntriesTask<K,V,U>
rights,
nextRight;
MapReduceEntriesTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceEntriesTask<K,V,U>
nextRight,
Function<
Map.
Entry<K,V>, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
reducer =
reducer;
}
public final U
getRawResult() { return
result; }
public final void
compute() {
final
Function<
Map.
Entry<K,V>, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceEntriesTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
reducer)).
fork();
}
U
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p)) != null)
r = (
r == null) ?
u :
reducer.
apply(
r,
u);
}
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceEntriesTask<K,V,U>
t = (
MapReduceEntriesTask<K,V,U>)
c,
s =
t.
rights;
while (
s != null) {
U
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceMappingsTask<K,V,U>
extends
BulkTask<K,V,U> {
final
BiFunction<? super K, ? super V, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
U
result;
MapReduceMappingsTask<K,V,U>
rights,
nextRight;
MapReduceMappingsTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceMappingsTask<K,V,U>
nextRight,
BiFunction<? super K, ? super V, ? extends U>
transformer,
BiFunction<? super U, ? super U, ? extends U>
reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
reducer =
reducer;
}
public final U
getRawResult() { return
result; }
public final void
compute() {
final
BiFunction<? super K, ? super V, ? extends U>
transformer;
final
BiFunction<? super U, ? super U, ? extends U>
reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceMappingsTask<K,V,U>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
reducer)).
fork();
}
U
r = null;
for (
Node<K,V>
p; (
p =
advance()) != null; ) {
U
u;
if ((
u =
transformer.
apply(
p.
key,
p.
val)) != null)
r = (
r == null) ?
u :
reducer.
apply(
r,
u);
}
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceMappingsTask<K,V,U>
t = (
MapReduceMappingsTask<K,V,U>)
c,
s =
t.
rights;
while (
s != null) {
U
tr,
sr;
if ((
sr =
s.
result) != null)
t.
result = (((
tr =
t.
result) == null) ?
sr :
reducer.
apply(
tr,
sr));
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceKeysToDoubleTask<K,V>
extends
BulkTask<K,V,
Double> {
final
ToDoubleFunction<? super K>
transformer;
final
DoubleBinaryOperator reducer;
final double
basis;
double
result;
MapReduceKeysToDoubleTask<K,V>
rights,
nextRight;
MapReduceKeysToDoubleTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceKeysToDoubleTask<K,V>
nextRight,
ToDoubleFunction<? super K>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Double getRawResult() { return
result; }
public final void
compute() {
final
ToDoubleFunction<? super K>
transformer;
final
DoubleBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
double
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceKeysToDoubleTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsDouble(
r,
transformer.
applyAsDouble(
p.
key));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceKeysToDoubleTask<K,V>
t = (
MapReduceKeysToDoubleTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsDouble(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceValuesToDoubleTask<K,V>
extends
BulkTask<K,V,
Double> {
final
ToDoubleFunction<? super V>
transformer;
final
DoubleBinaryOperator reducer;
final double
basis;
double
result;
MapReduceValuesToDoubleTask<K,V>
rights,
nextRight;
MapReduceValuesToDoubleTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceValuesToDoubleTask<K,V>
nextRight,
ToDoubleFunction<? super V>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Double getRawResult() { return
result; }
public final void
compute() {
final
ToDoubleFunction<? super V>
transformer;
final
DoubleBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
double
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceValuesToDoubleTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsDouble(
r,
transformer.
applyAsDouble(
p.
val));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceValuesToDoubleTask<K,V>
t = (
MapReduceValuesToDoubleTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsDouble(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceEntriesToDoubleTask<K,V>
extends
BulkTask<K,V,
Double> {
final
ToDoubleFunction<
Map.
Entry<K,V>>
transformer;
final
DoubleBinaryOperator reducer;
final double
basis;
double
result;
MapReduceEntriesToDoubleTask<K,V>
rights,
nextRight;
MapReduceEntriesToDoubleTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceEntriesToDoubleTask<K,V>
nextRight,
ToDoubleFunction<
Map.
Entry<K,V>>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Double getRawResult() { return
result; }
public final void
compute() {
final
ToDoubleFunction<
Map.
Entry<K,V>>
transformer;
final
DoubleBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
double
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceEntriesToDoubleTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsDouble(
r,
transformer.
applyAsDouble(
p));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceEntriesToDoubleTask<K,V>
t = (
MapReduceEntriesToDoubleTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsDouble(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceMappingsToDoubleTask<K,V>
extends
BulkTask<K,V,
Double> {
final
ToDoubleBiFunction<? super K, ? super V>
transformer;
final
DoubleBinaryOperator reducer;
final double
basis;
double
result;
MapReduceMappingsToDoubleTask<K,V>
rights,
nextRight;
MapReduceMappingsToDoubleTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceMappingsToDoubleTask<K,V>
nextRight,
ToDoubleBiFunction<? super K, ? super V>
transformer,
double
basis,
DoubleBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Double getRawResult() { return
result; }
public final void
compute() {
final
ToDoubleBiFunction<? super K, ? super V>
transformer;
final
DoubleBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
double
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceMappingsToDoubleTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsDouble(
r,
transformer.
applyAsDouble(
p.
key,
p.
val));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceMappingsToDoubleTask<K,V>
t = (
MapReduceMappingsToDoubleTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsDouble(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceKeysToLongTask<K,V>
extends
BulkTask<K,V,
Long> {
final
ToLongFunction<? super K>
transformer;
final
LongBinaryOperator reducer;
final long
basis;
long
result;
MapReduceKeysToLongTask<K,V>
rights,
nextRight;
MapReduceKeysToLongTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceKeysToLongTask<K,V>
nextRight,
ToLongFunction<? super K>
transformer,
long
basis,
LongBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Long getRawResult() { return
result; }
public final void
compute() {
final
ToLongFunction<? super K>
transformer;
final
LongBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
long
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceKeysToLongTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsLong(
r,
transformer.
applyAsLong(
p.
key));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceKeysToLongTask<K,V>
t = (
MapReduceKeysToLongTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsLong(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceValuesToLongTask<K,V>
extends
BulkTask<K,V,
Long> {
final
ToLongFunction<? super V>
transformer;
final
LongBinaryOperator reducer;
final long
basis;
long
result;
MapReduceValuesToLongTask<K,V>
rights,
nextRight;
MapReduceValuesToLongTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceValuesToLongTask<K,V>
nextRight,
ToLongFunction<? super V>
transformer,
long
basis,
LongBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Long getRawResult() { return
result; }
public final void
compute() {
final
ToLongFunction<? super V>
transformer;
final
LongBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
long
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceValuesToLongTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsLong(
r,
transformer.
applyAsLong(
p.
val));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceValuesToLongTask<K,V>
t = (
MapReduceValuesToLongTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsLong(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceEntriesToLongTask<K,V>
extends
BulkTask<K,V,
Long> {
final
ToLongFunction<
Map.
Entry<K,V>>
transformer;
final
LongBinaryOperator reducer;
final long
basis;
long
result;
MapReduceEntriesToLongTask<K,V>
rights,
nextRight;
MapReduceEntriesToLongTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceEntriesToLongTask<K,V>
nextRight,
ToLongFunction<
Map.
Entry<K,V>>
transformer,
long
basis,
LongBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Long getRawResult() { return
result; }
public final void
compute() {
final
ToLongFunction<
Map.
Entry<K,V>>
transformer;
final
LongBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
long
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceEntriesToLongTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsLong(
r,
transformer.
applyAsLong(
p));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceEntriesToLongTask<K,V>
t = (
MapReduceEntriesToLongTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsLong(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceMappingsToLongTask<K,V>
extends
BulkTask<K,V,
Long> {
final
ToLongBiFunction<? super K, ? super V>
transformer;
final
LongBinaryOperator reducer;
final long
basis;
long
result;
MapReduceMappingsToLongTask<K,V>
rights,
nextRight;
MapReduceMappingsToLongTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceMappingsToLongTask<K,V>
nextRight,
ToLongBiFunction<? super K, ? super V>
transformer,
long
basis,
LongBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Long getRawResult() { return
result; }
public final void
compute() {
final
ToLongBiFunction<? super K, ? super V>
transformer;
final
LongBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
long
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceMappingsToLongTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsLong(
r,
transformer.
applyAsLong(
p.
key,
p.
val));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceMappingsToLongTask<K,V>
t = (
MapReduceMappingsToLongTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsLong(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceKeysToIntTask<K,V>
extends
BulkTask<K,V,
Integer> {
final
ToIntFunction<? super K>
transformer;
final
IntBinaryOperator reducer;
final int
basis;
int
result;
MapReduceKeysToIntTask<K,V>
rights,
nextRight;
MapReduceKeysToIntTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceKeysToIntTask<K,V>
nextRight,
ToIntFunction<? super K>
transformer,
int
basis,
IntBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Integer getRawResult() { return
result; }
public final void
compute() {
final
ToIntFunction<? super K>
transformer;
final
IntBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
int
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceKeysToIntTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsInt(
r,
transformer.
applyAsInt(
p.
key));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceKeysToIntTask<K,V>
t = (
MapReduceKeysToIntTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsInt(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceValuesToIntTask<K,V>
extends
BulkTask<K,V,
Integer> {
final
ToIntFunction<? super V>
transformer;
final
IntBinaryOperator reducer;
final int
basis;
int
result;
MapReduceValuesToIntTask<K,V>
rights,
nextRight;
MapReduceValuesToIntTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceValuesToIntTask<K,V>
nextRight,
ToIntFunction<? super V>
transformer,
int
basis,
IntBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Integer getRawResult() { return
result; }
public final void
compute() {
final
ToIntFunction<? super V>
transformer;
final
IntBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
int
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceValuesToIntTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsInt(
r,
transformer.
applyAsInt(
p.
val));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceValuesToIntTask<K,V>
t = (
MapReduceValuesToIntTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsInt(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceEntriesToIntTask<K,V>
extends
BulkTask<K,V,
Integer> {
final
ToIntFunction<
Map.
Entry<K,V>>
transformer;
final
IntBinaryOperator reducer;
final int
basis;
int
result;
MapReduceEntriesToIntTask<K,V>
rights,
nextRight;
MapReduceEntriesToIntTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceEntriesToIntTask<K,V>
nextRight,
ToIntFunction<
Map.
Entry<K,V>>
transformer,
int
basis,
IntBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Integer getRawResult() { return
result; }
public final void
compute() {
final
ToIntFunction<
Map.
Entry<K,V>>
transformer;
final
IntBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
int
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceEntriesToIntTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsInt(
r,
transformer.
applyAsInt(
p));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceEntriesToIntTask<K,V>
t = (
MapReduceEntriesToIntTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsInt(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
@
SuppressWarnings("serial")
static final class
MapReduceMappingsToIntTask<K,V>
extends
BulkTask<K,V,
Integer> {
final
ToIntBiFunction<? super K, ? super V>
transformer;
final
IntBinaryOperator reducer;
final int
basis;
int
result;
MapReduceMappingsToIntTask<K,V>
rights,
nextRight;
MapReduceMappingsToIntTask
(
BulkTask<K,V,?>
p, int
b, int
i, int
f,
Node<K,V>[]
t,
MapReduceMappingsToIntTask<K,V>
nextRight,
ToIntBiFunction<? super K, ? super V>
transformer,
int
basis,
IntBinaryOperator reducer) {
super(
p,
b,
i,
f,
t); this.
nextRight =
nextRight;
this.
transformer =
transformer;
this.
basis =
basis; this.
reducer =
reducer;
}
public final
Integer getRawResult() { return
result; }
public final void
compute() {
final
ToIntBiFunction<? super K, ? super V>
transformer;
final
IntBinaryOperator reducer;
if ((
transformer = this.
transformer) != null &&
(
reducer = this.
reducer) != null) {
int
r = this.
basis;
for (int
i =
baseIndex,
f,
h;
batch > 0 &&
(
h = ((
f =
baseLimit) +
i) >>> 1) >
i;) {
addToPendingCount(1);
(
rights = new
MapReduceMappingsToIntTask<K,V>
(this,
batch >>>= 1,
baseLimit =
h,
f,
tab,
rights,
transformer,
r,
reducer)).
fork();
}
for (
Node<K,V>
p; (
p =
advance()) != null; )
r =
reducer.
applyAsInt(
r,
transformer.
applyAsInt(
p.
key,
p.
val));
result =
r;
CountedCompleter<?>
c;
for (
c =
firstComplete();
c != null;
c =
c.
nextComplete()) {
@
SuppressWarnings("unchecked")
MapReduceMappingsToIntTask<K,V>
t = (
MapReduceMappingsToIntTask<K,V>)
c,
s =
t.
rights;
while (
s != null) {
t.
result =
reducer.
applyAsInt(
t.
result,
s.
result);
s =
t.
rights =
s.
nextRight;
}
}
}
}
}
// Unsafe mechanics
private static final sun.misc.
Unsafe U;
private static final long
SIZECTL;
private static final long
TRANSFERINDEX;
private static final long
BASECOUNT;
private static final long
CELLSBUSY;
private static final long
CELLVALUE;
private static final long
ABASE;
private static final int
ASHIFT;
static {
try {
U = sun.misc.
Unsafe.
getUnsafe();
Class<?>
k =
ConcurrentHashMap.class;
SIZECTL =
U.
objectFieldOffset
(
k.
getDeclaredField("sizeCtl"));
TRANSFERINDEX =
U.
objectFieldOffset
(
k.
getDeclaredField("transferIndex"));
BASECOUNT =
U.
objectFieldOffset
(
k.
getDeclaredField("baseCount"));
CELLSBUSY =
U.
objectFieldOffset
(
k.
getDeclaredField("cellsBusy"));
Class<?>
ck =
CounterCell.class;
CELLVALUE =
U.
objectFieldOffset
(
ck.
getDeclaredField("value"));
Class<?>
ak =
Node[].class;
ABASE =
U.
arrayBaseOffset(
ak);
int
scale =
U.
arrayIndexScale(
ak);
if ((
scale & (
scale - 1)) != 0)
throw new
Error("data type scale not a power of two");
ASHIFT = 31 -
Integer.
numberOfLeadingZeros(
scale);
} catch (
Exception e) {
throw new
Error(
e);
}
}
}