/*
* Copyright (C) 2011 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.
BoundType.
CLOSED;
import com.google.common.annotations.
GwtCompatible;
import com.google.common.annotations.
GwtIncompatible;
import java.io.
Serializable;
import java.util.
Collection;
import javax.annotation.
Nullable;
/**
* An implementation of {@link ContiguousSet} that contains one or more elements.
*
* @author Gregory Kick
*/
@
GwtCompatible(emulated = true)
@
SuppressWarnings("unchecked") // allow ungenerified Comparable types
final class
RegularContiguousSet<C extends
Comparable> extends
ContiguousSet<C> {
private final
Range<C>
range;
RegularContiguousSet(
Range<C>
range,
DiscreteDomain<C>
domain) {
super(
domain);
this.
range =
range;
}
private
ContiguousSet<C>
intersectionInCurrentDomain(
Range<C>
other) {
return (
range.
isConnected(
other))
?
ContiguousSet.
create(
range.
intersection(
other),
domain)
: new
EmptyContiguousSet<C>(
domain);
}
@
Override ContiguousSet<C>
headSetImpl(C
toElement, boolean
inclusive) {
return
intersectionInCurrentDomain(
Range.
upTo(
toElement,
BoundType.
forBoolean(
inclusive)));
}
@
Override ContiguousSet<C>
subSetImpl(C
fromElement, boolean
fromInclusive, C
toElement,
boolean
toInclusive) {
if (
fromElement.
compareTo(
toElement) == 0 && !
fromInclusive && !
toInclusive) {
// Range would reject our attempt to create (x, x).
return new
EmptyContiguousSet<C>(
domain);
}
return
intersectionInCurrentDomain(
Range.
range(
fromElement,
BoundType.
forBoolean(
fromInclusive),
toElement,
BoundType.
forBoolean(
toInclusive)));
}
@
Override ContiguousSet<C>
tailSetImpl(C
fromElement, boolean
inclusive) {
return
intersectionInCurrentDomain(
Range.
downTo(
fromElement,
BoundType.
forBoolean(
inclusive)));
}
@
GwtIncompatible("not used by GWT emulation")
@
Override int
indexOf(
Object target) {
return
contains(
target) ? (int)
domain.
distance(
first(), (C)
target) : -1;
}
@
Override public
UnmodifiableIterator<C>
iterator() {
return new
AbstractSequentialIterator<C>(
first()) {
final C
last =
last();
@
Override
protected C
computeNext(C
previous) {
return
equalsOrThrow(
previous,
last) ? null :
domain.
next(
previous);
}
};
}
@
GwtIncompatible("NavigableSet")
@
Override public
UnmodifiableIterator<C>
descendingIterator() {
return new
AbstractSequentialIterator<C>(
last()) {
final C
first =
first();
@
Override
protected C
computeNext(C
previous) {
return
equalsOrThrow(
previous,
first) ? null :
domain.
previous(
previous);
}
};
}
private static boolean
equalsOrThrow(
Comparable<?>
left, @
Nullable Comparable<?>
right) {
return
right != null &&
Range.
compareOrThrow(
left,
right) == 0;
}
@
Override boolean
isPartialView() {
return false;
}
@
Override public C
first() {
return
range.
lowerBound.
leastValueAbove(
domain);
}
@
Override public C
last() {
return
range.
upperBound.
greatestValueBelow(
domain);
}
@
Override public int
size() {
long
distance =
domain.
distance(
first(),
last());
return (
distance >=
Integer.
MAX_VALUE) ?
Integer.
MAX_VALUE : (int)
distance + 1;
}
@
Override public boolean
contains(@
Nullable Object object) {
if (
object == null) {
return false;
}
try {
return
range.
contains((C)
object);
} catch (
ClassCastException e) {
return false;
}
}
@
Override public boolean
containsAll(
Collection<?>
targets) {
return
Collections2.
containsAllImpl(this,
targets);
}
@
Override public boolean
isEmpty() {
return false;
}
@
Override public
ContiguousSet<C>
intersection(
ContiguousSet<C>
other) {
checkNotNull(
other);
checkArgument(this.
domain.
equals(
other.
domain));
if (
other.
isEmpty()) {
return
other;
} else {
C
lowerEndpoint =
Ordering.
natural().
max(this.
first(),
other.
first());
C
upperEndpoint =
Ordering.
natural().
min(this.
last(),
other.
last());
return (
lowerEndpoint.
compareTo(
upperEndpoint) < 0)
?
ContiguousSet.
create(
Range.
closed(
lowerEndpoint,
upperEndpoint),
domain)
: new
EmptyContiguousSet<C>(
domain);
}
}
@
Override public
Range<C>
range() {
return
range(
CLOSED,
CLOSED);
}
@
Override public
Range<C>
range(
BoundType lowerBoundType,
BoundType upperBoundType) {
return
Range.
create(
range.
lowerBound.
withLowerBoundType(
lowerBoundType,
domain),
range.
upperBound.
withUpperBoundType(
upperBoundType,
domain));
}
@
Override public boolean
equals(@
Nullable Object object) {
if (
object == this) {
return true;
} else if (
object instanceof
RegularContiguousSet) {
RegularContiguousSet<?>
that = (
RegularContiguousSet<?>)
object;
if (this.
domain.
equals(
that.
domain)) {
return this.
first().
equals(
that.
first())
&& this.
last().
equals(
that.
last());
}
}
return super.equals(
object);
}
// copied to make sure not to use the GWT-emulated version
@
Override public int
hashCode() {
return
Sets.
hashCodeImpl(this);
}
@
GwtIncompatible("serialization")
private static final class
SerializedForm<C extends
Comparable> implements
Serializable {
final
Range<C>
range;
final
DiscreteDomain<C>
domain;
private
SerializedForm(
Range<C>
range,
DiscreteDomain<C>
domain) {
this.
range =
range;
this.
domain =
domain;
}
private
Object readResolve() {
return new
RegularContiguousSet<C>(
range,
domain);
}
}
@
GwtIncompatible("serialization")
@
Override Object writeReplace() {
return new
SerializedForm<C>(
range,
domain);
}
private static final long
serialVersionUID = 0;
}