/*
* Copyright (C) 2008 The Guava Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.common.collect;
import static com.google.common.base.
Preconditions.checkArgument;
import static com.google.common.base.
Preconditions.checkNotNull;
import static com.google.common.collect.
ObjectArrays.checkElementsNotNull;
import com.google.common.annotations.
GwtCompatible;
import com.google.common.annotations.
GwtIncompatible;
import java.io.
InvalidObjectException;
import java.io.
ObjectInputStream;
import java.io.
Serializable;
import java.util.
Arrays;
import java.util.
Collection;
import java.util.
Collections;
import java.util.
Comparator;
import java.util.
Iterator;
import java.util.
NavigableSet;
import java.util.
SortedSet;
import javax.annotation.
Nullable;
/**
* An immutable {@code SortedSet} that stores its elements in a sorted array.
* Some instances are ordered by an explicit comparator, while others follow the
* natural sort ordering of their elements. Either way, null elements are not
* supported.
*
* <p>Unlike {@link Collections#unmodifiableSortedSet}, which is a <i>view</i>
* of a separate collection that can still change, an instance of {@code
* ImmutableSortedSet} contains its own private data and will <i>never</i>
* change. This class is convenient for {@code public static final} sets
* ("constant sets") and also lets you easily make a "defensive copy" of a set
* provided to your class by a caller.
*
* <p>The sets returned by the {@link #headSet}, {@link #tailSet}, and
* {@link #subSet} methods share the same array as the original set, preventing
* that array from being garbage collected. If this is a concern, the data may
* be copied into a correctly-sized array by calling {@link #copyOfSorted}.
*
* <p><b>Note on element equivalence:</b> The {@link #contains(Object)},
* {@link #containsAll(Collection)}, and {@link #equals(Object)}
* implementations must check whether a provided object is equivalent to an
* element in the collection. Unlike most collections, an
* {@code ImmutableSortedSet} doesn't use {@link Object#equals} to determine if
* two elements are equivalent. Instead, with an explicit comparator, the
* following relation determines whether elements {@code x} and {@code y} are
* equivalent: <pre> {@code
*
* {(x, y) | comparator.compare(x, y) == 0}}</pre>
*
* <p>With natural ordering of elements, the following relation determines whether
* two elements are equivalent: <pre> {@code
*
* {(x, y) | x.compareTo(y) == 0}}</pre>
*
* <b>Warning:</b> Like most sets, an {@code ImmutableSortedSet} will not
* function correctly if an element is modified after being placed in the set.
* For this reason, and to avoid general confusion, it is strongly recommended
* to place only immutable objects into this collection.
*
* <p><b>Note:</b> Although this class is not final, it cannot be subclassed as
* it has no public or protected constructors. Thus, instances of this type are
* guaranteed to be immutable.
*
* <p>See the Guava User Guide article on <a href=
* "http://code.google.com/p/guava-libraries/wiki/ImmutableCollectionsExplained">
* immutable collections</a>.
*
* @see ImmutableSet
* @author Jared Levy
* @author Louis Wasserman
* @since 2.0 (imported from Google Collections Library; implements {@code NavigableSet} since 12.0)
*/
// TODO(benyu): benchmark and optimize all creation paths, which are a mess now
@
GwtCompatible(serializable = true, emulated = true)
@
SuppressWarnings("serial") // we're overriding default serialization
public abstract class
ImmutableSortedSet<E> extends
ImmutableSortedSetFauxverideShim<E>
implements
NavigableSet<E>,
SortedIterable<E> {
private static final
Comparator<
Comparable>
NATURAL_ORDER =
Ordering.
natural();
private static final
ImmutableSortedSet<
Comparable>
NATURAL_EMPTY_SET =
new
EmptyImmutableSortedSet<
Comparable>(
NATURAL_ORDER);
@
SuppressWarnings("unchecked")
private static <E>
ImmutableSortedSet<E>
emptySet() {
return (
ImmutableSortedSet<E>)
NATURAL_EMPTY_SET;
}
static <E>
ImmutableSortedSet<E>
emptySet(
Comparator<? super E>
comparator) {
if (
NATURAL_ORDER.
equals(
comparator)) {
return
emptySet();
} else {
return new
EmptyImmutableSortedSet<E>(
comparator);
}
}
/**
* Returns the empty immutable sorted set.
*/
public static <E>
ImmutableSortedSet<E>
of() {
return
emptySet();
}
/**
* Returns an immutable sorted set containing a single element.
*/
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
of(
E
element) {
return new
RegularImmutableSortedSet<E>(
ImmutableList.
of(
element),
Ordering.
natural());
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@link Comparable#compareTo}, only the first one specified is included.
*
* @throws NullPointerException if any element is null
*/
@
SuppressWarnings("unchecked")
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
of(
E
e1, E
e2) {
return
construct(
Ordering.
natural(), 2,
e1,
e2);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@link Comparable#compareTo}, only the first one specified is included.
*
* @throws NullPointerException if any element is null
*/
@
SuppressWarnings("unchecked")
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
of(
E
e1, E
e2, E
e3) {
return
construct(
Ordering.
natural(), 3,
e1,
e2,
e3);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@link Comparable#compareTo}, only the first one specified is included.
*
* @throws NullPointerException if any element is null
*/
@
SuppressWarnings("unchecked")
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
of(
E
e1, E
e2, E
e3, E
e4) {
return
construct(
Ordering.
natural(), 4,
e1,
e2,
e3,
e4);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@link Comparable#compareTo}, only the first one specified is included.
*
* @throws NullPointerException if any element is null
*/
@
SuppressWarnings("unchecked")
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
of(
E
e1, E
e2, E
e3, E
e4, E
e5) {
return
construct(
Ordering.
natural(), 5,
e1,
e2,
e3,
e4,
e5);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@link Comparable#compareTo}, only the first one specified is included.
*
* @throws NullPointerException if any element is null
* @since 3.0 (source-compatible since 2.0)
*/
@
SuppressWarnings("unchecked")
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
of(
E
e1, E
e2, E
e3, E
e4, E
e5, E
e6, E...
remaining) {
Comparable[]
contents = new
Comparable[6 +
remaining.length];
contents[0] =
e1;
contents[1] =
e2;
contents[2] =
e3;
contents[3] =
e4;
contents[4] =
e5;
contents[5] =
e6;
System.
arraycopy(
remaining, 0,
contents, 6,
remaining.length);
return
construct(
Ordering.
natural(),
contents.length, (E[])
contents);
}
// TODO(kevinb): Consider factory methods that reject duplicates
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@link Comparable#compareTo}, only the first one specified is included.
*
* @throws NullPointerException if any of {@code elements} is null
* @since 3.0
*/
public static <E extends
Comparable<? super E>>
ImmutableSortedSet<E>
copyOf(
E[]
elements) {
return
construct(
Ordering.
natural(),
elements.length,
elements.
clone());
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@code compareTo()}, only the first one specified is included. To create a
* copy of a {@code SortedSet} that preserves the comparator, call {@link
* #copyOfSorted} instead. This method iterates over {@code elements} at most
* once.
*
* <p>Note that if {@code s} is a {@code Set<String>}, then {@code
* ImmutableSortedSet.copyOf(s)} returns an {@code ImmutableSortedSet<String>}
* containing each of the strings in {@code s}, while {@code
* ImmutableSortedSet.of(s)} returns an {@code
* ImmutableSortedSet<Set<String>>} containing one element (the given set
* itself).
*
* <p>Despite the method name, this method attempts to avoid actually copying
* the data when it is safe to do so. The exact circumstances under which a
* copy will or will not be performed are undocumented and subject to change.
*
* <p>This method is not type-safe, as it may be called on elements that are
* not mutually comparable.
*
* @throws ClassCastException if the elements are not mutually comparable
* @throws NullPointerException if any of {@code elements} is null
*/
public static <E>
ImmutableSortedSet<E>
copyOf(
Iterable<? extends E>
elements) {
// Hack around E not being a subtype of Comparable.
// Unsafe, see ImmutableSortedSetFauxverideShim.
@
SuppressWarnings("unchecked")
Ordering<E>
naturalOrder = (
Ordering<E>)
Ordering.<
Comparable>
natural();
return
copyOf(
naturalOrder,
elements);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@code compareTo()}, only the first one specified is included. To create a
* copy of a {@code SortedSet} that preserves the comparator, call
* {@link #copyOfSorted} instead. This method iterates over {@code elements}
* at most once.
*
* <p>Note that if {@code s} is a {@code Set<String>}, then
* {@code ImmutableSortedSet.copyOf(s)} returns an
* {@code ImmutableSortedSet<String>} containing each of the strings in
* {@code s}, while {@code ImmutableSortedSet.of(s)} returns an
* {@code ImmutableSortedSet<Set<String>>} containing one element (the given
* set itself).
*
* <p><b>Note:</b> Despite what the method name suggests, if {@code elements}
* is an {@code ImmutableSortedSet}, it may be returned instead of a copy.
*
* <p>This method is not type-safe, as it may be called on elements that are
* not mutually comparable.
*
* <p>This method is safe to use even when {@code elements} is a synchronized
* or concurrent collection that is currently being modified by another
* thread.
*
* @throws ClassCastException if the elements are not mutually comparable
* @throws NullPointerException if any of {@code elements} is null
* @since 7.0 (source-compatible since 2.0)
*/
public static <E>
ImmutableSortedSet<E>
copyOf(
Collection<? extends E>
elements) {
// Hack around E not being a subtype of Comparable.
// Unsafe, see ImmutableSortedSetFauxverideShim.
@
SuppressWarnings("unchecked")
Ordering<E>
naturalOrder = (
Ordering<E>)
Ordering.<
Comparable>
natural();
return
copyOf(
naturalOrder,
elements);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* their natural ordering. When multiple elements are equivalent according to
* {@code compareTo()}, only the first one specified is included.
*
* <p>This method is not type-safe, as it may be called on elements that are
* not mutually comparable.
*
* @throws ClassCastException if the elements are not mutually comparable
* @throws NullPointerException if any of {@code elements} is null
*/
public static <E>
ImmutableSortedSet<E>
copyOf(
Iterator<? extends E>
elements) {
// Hack around E not being a subtype of Comparable.
// Unsafe, see ImmutableSortedSetFauxverideShim.
@
SuppressWarnings("unchecked")
Ordering<E>
naturalOrder = (
Ordering<E>)
Ordering.<
Comparable>
natural();
return
copyOf(
naturalOrder,
elements);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* the given {@code Comparator}. When multiple elements are equivalent
* according to {@code compareTo()}, only the first one specified is
* included.
*
* @throws NullPointerException if {@code comparator} or any of
* {@code elements} is null
*/
public static <E>
ImmutableSortedSet<E>
copyOf(
Comparator<? super E>
comparator,
Iterator<? extends E>
elements) {
return new
Builder<E>(
comparator).
addAll(
elements).
build();
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* the given {@code Comparator}. When multiple elements are equivalent
* according to {@code compare()}, only the first one specified is
* included. This method iterates over {@code elements} at most once.
*
* <p>Despite the method name, this method attempts to avoid actually copying
* the data when it is safe to do so. The exact circumstances under which a
* copy will or will not be performed are undocumented and subject to change.
*
* @throws NullPointerException if {@code comparator} or any of {@code
* elements} is null
*/
public static <E>
ImmutableSortedSet<E>
copyOf(
Comparator<? super E>
comparator,
Iterable<? extends E>
elements) {
checkNotNull(
comparator);
boolean
hasSameComparator =
SortedIterables.
hasSameComparator(
comparator,
elements);
if (
hasSameComparator && (
elements instanceof
ImmutableSortedSet)) {
@
SuppressWarnings("unchecked")
ImmutableSortedSet<E>
original = (
ImmutableSortedSet<E>)
elements;
if (!
original.
isPartialView()) {
return
original;
}
}
@
SuppressWarnings("unchecked") // elements only contains E's; it's safe.
E[]
array = (E[])
Iterables.
toArray(
elements);
return
construct(
comparator,
array.length,
array);
}
/**
* Returns an immutable sorted set containing the given elements sorted by
* the given {@code Comparator}. When multiple elements are equivalent
* according to {@code compareTo()}, only the first one specified is
* included.
*
* <p>Despite the method name, this method attempts to avoid actually copying
* the data when it is safe to do so. The exact circumstances under which a
* copy will or will not be performed are undocumented and subject to change.
*
* <p>This method is safe to use even when {@code elements} is a synchronized
* or concurrent collection that is currently being modified by another
* thread.
*
* @throws NullPointerException if {@code comparator} or any of
* {@code elements} is null
* @since 7.0 (source-compatible since 2.0)
*/
public static <E>
ImmutableSortedSet<E>
copyOf(
Comparator<? super E>
comparator,
Collection<? extends E>
elements) {
return
copyOf(
comparator, (
Iterable<? extends E>)
elements);
}
/**
* Returns an immutable sorted set containing the elements of a sorted set,
* sorted by the same {@code Comparator}. That behavior differs from {@link
* #copyOf(Iterable)}, which always uses the natural ordering of the
* elements.
*
* <p>Despite the method name, this method attempts to avoid actually copying
* the data when it is safe to do so. The exact circumstances under which a
* copy will or will not be performed are undocumented and subject to change.
*
* <p>This method is safe to use even when {@code sortedSet} is a synchronized
* or concurrent collection that is currently being modified by another
* thread.
*
* @throws NullPointerException if {@code sortedSet} or any of its elements
* is null
*/
public static <E>
ImmutableSortedSet<E>
copyOfSorted(
SortedSet<E>
sortedSet) {
Comparator<? super E>
comparator =
SortedIterables.
comparator(
sortedSet);
ImmutableList<E>
list =
ImmutableList.
copyOf(
sortedSet);
if (
list.
isEmpty()) {
return
emptySet(
comparator);
} else {
return new
RegularImmutableSortedSet<E>(
list,
comparator);
}
}
/**
* Constructs an {@code ImmutableSortedSet} from the first {@code n} elements of
* {@code contents}. If {@code k} is the size of the returned {@code ImmutableSortedSet}, then
* the sorted unique elements are in the first {@code k} positions of {@code contents}, and
* {@code contents[i] == null} for {@code k <= i < n}.
*
* <p>If {@code k == contents.length}, then {@code contents} may no longer be safe for
* modification.
*
* @throws NullPointerException if any of the first {@code n} elements of {@code contents} is
* null
*/
static <E>
ImmutableSortedSet<E>
construct(
Comparator<? super E>
comparator, int
n, E...
contents) {
if (
n == 0) {
return
emptySet(
comparator);
}
checkElementsNotNull(
contents,
n);
Arrays.
sort(
contents, 0,
n,
comparator);
int
uniques = 1;
for (int
i = 1;
i <
n;
i++) {
E
cur =
contents[
i];
E
prev =
contents[
uniques - 1];
if (
comparator.
compare(
cur,
prev) != 0) {
contents[
uniques++] =
cur;
}
}
Arrays.
fill(
contents,
uniques,
n, null);
return new
RegularImmutableSortedSet<E>(
ImmutableList.<E>
asImmutableList(
contents,
uniques),
comparator);
}
/**
* Returns a builder that creates immutable sorted sets with an explicit
* comparator. If the comparator has a more general type than the set being
* generated, such as creating a {@code SortedSet<Integer>} with a
* {@code Comparator<Number>}, use the {@link Builder} constructor instead.
*
* @throws NullPointerException if {@code comparator} is null
*/
public static <E>
Builder<E>
orderedBy(
Comparator<E>
comparator) {
return new
Builder<E>(
comparator);
}
/**
* Returns a builder that creates immutable sorted sets whose elements are
* ordered by the reverse of their natural ordering.
*/
public static <E extends
Comparable<?>>
Builder<E>
reverseOrder() {
return new
Builder<E>(
Ordering.
natural().
reverse());
}
/**
* Returns a builder that creates immutable sorted sets whose elements are
* ordered by their natural ordering. The sorted sets use {@link
* Ordering#natural()} as the comparator. This method provides more
* type-safety than {@link #builder}, as it can be called only for classes
* that implement {@link Comparable}.
*/
public static <E extends
Comparable<?>>
Builder<E>
naturalOrder() {
return new
Builder<E>(
Ordering.
natural());
}
/**
* A builder for creating immutable sorted set instances, especially {@code
* public static final} sets ("constant sets"), with a given comparator.
* Example: <pre> {@code
*
* public static final ImmutableSortedSet<Number> LUCKY_NUMBERS =
* new ImmutableSortedSet.Builder<Number>(ODDS_FIRST_COMPARATOR)
* .addAll(SINGLE_DIGIT_PRIMES)
* .add(42)
* .build();}</pre>
*
* <p>Builder instances can be reused; it is safe to call {@link #build} multiple
* times to build multiple sets in series. Each set is a superset of the set
* created before it.
*
* @since 2.0 (imported from Google Collections Library)
*/
public static final class
Builder<E> extends
ImmutableSet.
Builder<E> {
private final
Comparator<? super E>
comparator;
/**
* Creates a new builder. The returned builder is equivalent to the builder
* generated by {@link ImmutableSortedSet#orderedBy}.
*/
public
Builder(
Comparator<? super E>
comparator) {
this.
comparator =
checkNotNull(
comparator);
}
/**
* Adds {@code element} to the {@code ImmutableSortedSet}. If the
* {@code ImmutableSortedSet} already contains {@code element}, then
* {@code add} has no effect. (only the previously added element
* is retained).
*
* @param element the element to add
* @return this {@code Builder} object
* @throws NullPointerException if {@code element} is null
*/
@
Override public
Builder<E>
add(E
element) {
super.add(
element);
return this;
}
/**
* Adds each element of {@code elements} to the {@code ImmutableSortedSet},
* ignoring duplicate elements (only the first duplicate element is added).
*
* @param elements the elements to add
* @return this {@code Builder} object
* @throws NullPointerException if {@code elements} contains a null element
*/
@
Override public
Builder<E>
add(E...
elements) {
super.add(
elements);
return this;
}
/**
* Adds each element of {@code elements} to the {@code ImmutableSortedSet},
* ignoring duplicate elements (only the first duplicate element is added).
*
* @param elements the elements to add to the {@code ImmutableSortedSet}
* @return this {@code Builder} object
* @throws NullPointerException if {@code elements} contains a null element
*/
@
Override public
Builder<E>
addAll(
Iterable<? extends E>
elements) {
super.addAll(
elements);
return this;
}
/**
* Adds each element of {@code elements} to the {@code ImmutableSortedSet},
* ignoring duplicate elements (only the first duplicate element is added).
*
* @param elements the elements to add to the {@code ImmutableSortedSet}
* @return this {@code Builder} object
* @throws NullPointerException if {@code elements} contains a null element
*/
@
Override public
Builder<E>
addAll(
Iterator<? extends E>
elements) {
super.addAll(
elements);
return this;
}
/**
* Returns a newly-created {@code ImmutableSortedSet} based on the contents
* of the {@code Builder} and its comparator.
*/
@
Override public
ImmutableSortedSet<E>
build() {
@
SuppressWarnings("unchecked") // we're careful to put only E's in here
E[]
contentsArray = (E[])
contents;
ImmutableSortedSet<E>
result =
construct(
comparator,
size,
contentsArray);
this.
size =
result.
size(); // we eliminated duplicates in-place in contentsArray
return
result;
}
}
int
unsafeCompare(
Object a,
Object b) {
return
unsafeCompare(
comparator,
a,
b);
}
static int
unsafeCompare(
Comparator<?>
comparator,
Object a,
Object b) {
// Pretend the comparator can compare anything. If it turns out it can't
// compare a and b, we should get a CCE on the subsequent line. Only methods
// that are spec'd to throw CCE should call this.
@
SuppressWarnings("unchecked")
Comparator<
Object>
unsafeComparator = (
Comparator<
Object>)
comparator;
return
unsafeComparator.
compare(
a,
b);
}
final transient
Comparator<? super E>
comparator;
ImmutableSortedSet(
Comparator<? super E>
comparator) {
this.
comparator =
comparator;
}
/**
* Returns the comparator that orders the elements, which is
* {@link Ordering#natural()} when the natural ordering of the
* elements is used. Note that its behavior is not consistent with
* {@link SortedSet#comparator()}, which returns {@code null} to indicate
* natural ordering.
*/
@
Override
public
Comparator<? super E>
comparator() {
return
comparator;
}
@
Override // needed to unify the iterator() methods in Collection and SortedIterable
public abstract
UnmodifiableIterator<E>
iterator();
/**
* {@inheritDoc}
*
* <p>This method returns a serializable {@code ImmutableSortedSet}.
*
* <p>The {@link SortedSet#headSet} documentation states that a subset of a
* subset throws an {@link IllegalArgumentException} if passed a
* {@code toElement} greater than an earlier {@code toElement}. However, this
* method doesn't throw an exception in that situation, but instead keeps the
* original {@code toElement}.
*/
@
Override
public
ImmutableSortedSet<E>
headSet(E
toElement) {
return
headSet(
toElement, false);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public
ImmutableSortedSet<E>
headSet(E
toElement, boolean
inclusive) {
return
headSetImpl(
checkNotNull(
toElement),
inclusive);
}
/**
* {@inheritDoc}
*
* <p>This method returns a serializable {@code ImmutableSortedSet}.
*
* <p>The {@link SortedSet#subSet} documentation states that a subset of a
* subset throws an {@link IllegalArgumentException} if passed a
* {@code fromElement} smaller than an earlier {@code fromElement}. However,
* this method doesn't throw an exception in that situation, but instead keeps
* the original {@code fromElement}. Similarly, this method keeps the
* original {@code toElement}, instead of throwing an exception, if passed a
* {@code toElement} greater than an earlier {@code toElement}.
*/
@
Override
public
ImmutableSortedSet<E>
subSet(E
fromElement, E
toElement) {
return
subSet(
fromElement, true,
toElement, false);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public
ImmutableSortedSet<E>
subSet(
E
fromElement, boolean
fromInclusive, E
toElement, boolean
toInclusive) {
checkNotNull(
fromElement);
checkNotNull(
toElement);
checkArgument(
comparator.
compare(
fromElement,
toElement) <= 0);
return
subSetImpl(
fromElement,
fromInclusive,
toElement,
toInclusive);
}
/**
* {@inheritDoc}
*
* <p>This method returns a serializable {@code ImmutableSortedSet}.
*
* <p>The {@link SortedSet#tailSet} documentation states that a subset of a
* subset throws an {@link IllegalArgumentException} if passed a
* {@code fromElement} smaller than an earlier {@code fromElement}. However,
* this method doesn't throw an exception in that situation, but instead keeps
* the original {@code fromElement}.
*/
@
Override
public
ImmutableSortedSet<E>
tailSet(E
fromElement) {
return
tailSet(
fromElement, true);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public
ImmutableSortedSet<E>
tailSet(E
fromElement, boolean
inclusive) {
return
tailSetImpl(
checkNotNull(
fromElement),
inclusive);
}
/*
* These methods perform most headSet, subSet, and tailSet logic, besides
* parameter validation.
*/
abstract
ImmutableSortedSet<E>
headSetImpl(E
toElement, boolean
inclusive);
abstract
ImmutableSortedSet<E>
subSetImpl(
E
fromElement, boolean
fromInclusive, E
toElement, boolean
toInclusive);
abstract
ImmutableSortedSet<E>
tailSetImpl(E
fromElement, boolean
inclusive);
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public E
lower(E
e) {
return
Iterators.
getNext(
headSet(
e, false).
descendingIterator(), null);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public E
floor(E
e) {
return
Iterators.
getNext(
headSet(
e, true).
descendingIterator(), null);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public E
ceiling(E
e) {
return
Iterables.
getFirst(
tailSet(
e, true), null);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public E
higher(E
e) {
return
Iterables.
getFirst(
tailSet(
e, false), null);
}
@
Override
public E
first() {
return
iterator().
next();
}
@
Override
public E
last() {
return
descendingIterator().
next();
}
/**
* Guaranteed to throw an exception and leave the set unmodified.
*
* @since 12.0
* @throws UnsupportedOperationException always
* @deprecated Unsupported operation.
*/
@
Deprecated
@
GwtIncompatible("NavigableSet")
@
Override
public final E
pollFirst() {
throw new
UnsupportedOperationException();
}
/**
* Guaranteed to throw an exception and leave the set unmodified.
*
* @since 12.0
* @throws UnsupportedOperationException always
* @deprecated Unsupported operation.
*/
@
Deprecated
@
GwtIncompatible("NavigableSet")
@
Override
public final E
pollLast() {
throw new
UnsupportedOperationException();
}
@
GwtIncompatible("NavigableSet")
transient
ImmutableSortedSet<E>
descendingSet;
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public
ImmutableSortedSet<E>
descendingSet() {
// racy single-check idiom
ImmutableSortedSet<E>
result =
descendingSet;
if (
result == null) {
result =
descendingSet =
createDescendingSet();
result.
descendingSet = this;
}
return
result;
}
@
GwtIncompatible("NavigableSet")
ImmutableSortedSet<E>
createDescendingSet() {
return new
DescendingImmutableSortedSet<E>(this);
}
/**
* @since 12.0
*/
@
GwtIncompatible("NavigableSet")
@
Override
public abstract
UnmodifiableIterator<E>
descendingIterator();
/**
* Returns the position of an element within the set, or -1 if not present.
*/
abstract int
indexOf(@
Nullable Object target);
/*
* This class is used to serialize all ImmutableSortedSet instances,
* regardless of implementation type. It captures their "logical contents"
* only. This is necessary to ensure that the existence of a particular
* implementation type is an implementation detail.
*/
private static class
SerializedForm<E> implements
Serializable {
final
Comparator<? super E>
comparator;
final
Object[]
elements;
public
SerializedForm(
Comparator<? super E>
comparator,
Object[]
elements) {
this.
comparator =
comparator;
this.
elements =
elements;
}
@
SuppressWarnings("unchecked")
Object readResolve() {
return new
Builder<E>(
comparator).
add((E[])
elements).
build();
}
private static final long
serialVersionUID = 0;
}
private void
readObject(
ObjectInputStream stream)
throws
InvalidObjectException {
throw new
InvalidObjectException("Use SerializedForm");
}
@
Override Object writeReplace() {
return new
SerializedForm<E>(
comparator,
toArray());
}
}