com.google.common.collect.SortedMultisets Maven / Gradle / Ivy
/*
* 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.collect.BoundType.CLOSED;
import static com.google.common.collect.BoundType.OPEN;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.collect.Multiset.Entry;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.SortedSet;
import javax.annotation.Nullable;
/**
* Provides static utility methods for creating and working with
* {@link SortedMultiset} instances.
*
* @author Louis Wasserman
*/
@GwtCompatible(emulated = true)
final class SortedMultisets {
private SortedMultisets() {
}
/**
* A skeleton implementation for {@link SortedMultiset#elementSet}.
*/
static class ElementSet extends Multisets.ElementSet implements
SortedSet {
private final SortedMultiset multiset;
ElementSet(SortedMultiset multiset) {
this.multiset = multiset;
}
@Override final SortedMultiset multiset() {
return multiset;
}
@Override public Comparator super E> comparator() {
return multiset().comparator();
}
@Override public SortedSet subSet(E fromElement, E toElement) {
return multiset().subMultiset(fromElement, CLOSED, toElement, OPEN).elementSet();
}
@Override public SortedSet headSet(E toElement) {
return multiset().headMultiset(toElement, OPEN).elementSet();
}
@Override public SortedSet tailSet(E fromElement) {
return multiset().tailMultiset(fromElement, CLOSED).elementSet();
}
@Override public E first() {
return getElementOrThrow(multiset().firstEntry());
}
@Override public E last() {
return getElementOrThrow(multiset().lastEntry());
}
}
/**
* A skeleton navigable implementation for {@link SortedMultiset#elementSet}.
*/
@GwtIncompatible("Navigable")
static class NavigableElementSet extends ElementSet implements NavigableSet {
NavigableElementSet(SortedMultiset multiset) {
super(multiset);
}
@Override
public E lower(E e) {
return getElementOrNull(multiset().headMultiset(e, OPEN).lastEntry());
}
@Override
public E floor(E e) {
return getElementOrNull(multiset().headMultiset(e, CLOSED).lastEntry());
}
@Override
public E ceiling(E e) {
return getElementOrNull(multiset().tailMultiset(e, CLOSED).firstEntry());
}
@Override
public E higher(E e) {
return getElementOrNull(multiset().tailMultiset(e, OPEN).firstEntry());
}
@Override
public NavigableSet descendingSet() {
return new NavigableElementSet(multiset().descendingMultiset());
}
@Override
public Iterator descendingIterator() {
return descendingSet().iterator();
}
@Override
public E pollFirst() {
return getElementOrNull(multiset().pollFirstEntry());
}
@Override
public E pollLast() {
return getElementOrNull(multiset().pollLastEntry());
}
@Override
public NavigableSet subSet(
E fromElement, boolean fromInclusive, E toElement, boolean toInclusive) {
return new NavigableElementSet(multiset().subMultiset(
fromElement, BoundType.forBoolean(fromInclusive),
toElement, BoundType.forBoolean(toInclusive)));
}
@Override
public NavigableSet headSet(E toElement, boolean inclusive) {
return new NavigableElementSet(
multiset().headMultiset(toElement, BoundType.forBoolean(inclusive)));
}
@Override
public NavigableSet tailSet(E fromElement, boolean inclusive) {
return new NavigableElementSet(
multiset().tailMultiset(fromElement, BoundType.forBoolean(inclusive)));
}
}
private static E getElementOrThrow(Entry entry) {
if (entry == null) {
throw new NoSuchElementException();
}
return entry.getElement();
}
private static E getElementOrNull(@Nullable Entry entry) {
return (entry == null) ? null : entry.getElement();
}
}