Multimaps.java
/*
* Copyright (C) 2007 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.checkNotNull;
import static com.google.common.collect.CollectPreconditions.checkNonnegative;
import static com.google.common.collect.CollectPreconditions.checkRemove;
import com.google.common.annotations.Beta;
import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.base.Function;
import com.google.common.base.Predicate;
import com.google.common.base.Predicates;
import com.google.common.base.Supplier;
import com.google.common.collect.Maps.EntryTransformer;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import com.google.errorprone.annotations.concurrent.LazyInit;
import com.google.j2objc.annotations.Weak;
import com.google.j2objc.annotations.WeakOuter;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.AbstractCollection;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NavigableSet;
import java.util.NoSuchElementException;
import java.util.Set;
import java.util.SortedSet;
import java.util.Spliterator;
import java.util.function.BiConsumer;
import java.util.function.Consumer;
import java.util.stream.Collector;
import java.util.stream.Stream;
import org.checkerframework.checker.nullness.qual.Nullable;
/**
* Provides static methods acting on or generating a {@code Multimap}.
*
* <p>See the Guava User Guide article on <a href=
* "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#multimaps"> {@code
* Multimaps}</a>.
*
* @author Jared Levy
* @author Robert Konigsberg
* @author Mike Bostock
* @author Louis Wasserman
* @since 2.0
*/
@GwtCompatible(emulated = true)
public final class Multimaps {
private Multimaps() {}
/**
* Returns a {@code Collector} accumulating entries into a {@code Multimap} generated from the
* specified supplier. The keys and values of the entries are the result of applying the provided
* mapping functions to the input elements, accumulated in the encounter order of the stream.
*
* <p>Example:
*
* <pre>{@code
* static final ListMultimap<Character, String> FIRST_LETTER_MULTIMAP =
* Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
* .collect(
* toMultimap(
* str -> str.charAt(0),
* str -> str.substring(1),
* MultimapBuilder.treeKeys().arrayListValues()::build));
*
* // is equivalent to
*
* static final ListMultimap<Character, String> FIRST_LETTER_MULTIMAP;
*
* static {
* FIRST_LETTER_MULTIMAP = MultimapBuilder.treeKeys().arrayListValues().build();
* FIRST_LETTER_MULTIMAP.put('b', "anana");
* FIRST_LETTER_MULTIMAP.put('a', "pple");
* FIRST_LETTER_MULTIMAP.put('a', "sparagus");
* FIRST_LETTER_MULTIMAP.put('c', "arrot");
* FIRST_LETTER_MULTIMAP.put('c', "herry");
* }
* }</pre>
*
* <p>To collect to an {@link ImmutableMultimap}, use either {@link
* ImmutableSetMultimap#toImmutableSetMultimap} or {@link
* ImmutableListMultimap#toImmutableListMultimap}.
*
* @since 21.0
*/
public static <T, K, V, M extends Multimap<K, V>> Collector<T, ?, M> toMultimap(
java.util.function.Function<? super T, ? extends K> keyFunction,
java.util.function.Function<? super T, ? extends V> valueFunction,
java.util.function.Supplier<M> multimapSupplier) {
return CollectCollectors.toMultimap(keyFunction, valueFunction, multimapSupplier);
}
/**
* Returns a {@code Collector} accumulating entries into a {@code Multimap} generated from the
* specified supplier. Each input element is mapped to a key and a stream of values, each of which
* are put into the resulting {@code Multimap}, in the encounter order of the stream and the
* encounter order of the streams of values.
*
* <p>Example:
*
* <pre>{@code
* static final ListMultimap<Character, Character> FIRST_LETTER_MULTIMAP =
* Stream.of("banana", "apple", "carrot", "asparagus", "cherry")
* .collect(
* flatteningToMultimap(
* str -> str.charAt(0),
* str -> str.substring(1).chars().mapToObj(c -> (char) c),
* MultimapBuilder.linkedHashKeys().arrayListValues()::build));
*
* // is equivalent to
*
* static final ListMultimap<Character, Character> FIRST_LETTER_MULTIMAP;
*
* static {
* FIRST_LETTER_MULTIMAP = MultimapBuilder.linkedHashKeys().arrayListValues().build();
* FIRST_LETTER_MULTIMAP.putAll('b', Arrays.asList('a', 'n', 'a', 'n', 'a'));
* FIRST_LETTER_MULTIMAP.putAll('a', Arrays.asList('p', 'p', 'l', 'e'));
* FIRST_LETTER_MULTIMAP.putAll('c', Arrays.asList('a', 'r', 'r', 'o', 't'));
* FIRST_LETTER_MULTIMAP.putAll('a', Arrays.asList('s', 'p', 'a', 'r', 'a', 'g', 'u', 's'));
* FIRST_LETTER_MULTIMAP.putAll('c', Arrays.asList('h', 'e', 'r', 'r', 'y'));
* }
* }</pre>
*
* @since 21.0
*/
@Beta
public static <T, K, V, M extends Multimap<K, V>> Collector<T, ?, M> flatteningToMultimap(
java.util.function.Function<? super T, ? extends K> keyFunction,
java.util.function.Function<? super T, ? extends Stream<? extends V>> valueFunction,
java.util.function.Supplier<M> multimapSupplier) {
return CollectCollectors.flatteningToMultimap(keyFunction, valueFunction, multimapSupplier);
}
/**
* Creates a new {@code Multimap} backed by {@code map}, whose internal value collections are
* generated by {@code factory}.
*
* <p><b>Warning: do not use</b> this method when the collections returned by {@code factory}
* implement either {@link List} or {@code Set}! Use the more specific method {@link
* #newListMultimap}, {@link #newSetMultimap} or {@link #newSortedSetMultimap} instead, to avoid
* very surprising behavior from {@link Multimap#equals}.
*
* <p>The {@code factory}-generated and {@code map} classes determine the multimap iteration
* order. They also specify the behavior of the {@code equals}, {@code hashCode}, and {@code
* toString} methods for the multimap and its returned views. However, the multimap's {@code get}
* method returns instances of a different class than {@code factory.get()} does.
*
* <p>The multimap is serializable if {@code map}, {@code factory}, the collections generated by
* {@code factory}, and the multimap contents are all serializable.
*
* <p>The multimap is not threadsafe when any concurrent operations update the multimap, even if
* {@code map} and the instances generated by {@code factory} are. Concurrent read operations will
* work correctly. To allow concurrent update operations, wrap the multimap with a call to {@link
* #synchronizedMultimap}.
*
* <p>Call this method only when the simpler methods {@link ArrayListMultimap#create()}, {@link
* HashMultimap#create()}, {@link LinkedHashMultimap#create()}, {@link
* LinkedListMultimap#create()}, {@link TreeMultimap#create()}, and {@link
* TreeMultimap#create(Comparator, Comparator)} won't suffice.
*
* <p>Note: the multimap assumes complete ownership over of {@code map} and the collections
* returned by {@code factory}. Those objects should not be manually updated and they should not
* use soft, weak, or phantom references.
*
* @param map place to store the mapping from each key to its corresponding values
* @param factory supplier of new, empty collections that will each hold all values for a given
* key
* @throws IllegalArgumentException if {@code map} is not empty
*/
public static <K, V> Multimap<K, V> newMultimap(
Map<K, Collection<V>> map, final Supplier<? extends Collection<V>> factory) {
return new CustomMultimap<>(map, factory);
}
private static class CustomMultimap<K, V> extends AbstractMapBasedMultimap<K, V> {
transient Supplier<? extends Collection<V>> factory;
CustomMultimap(Map<K, Collection<V>> map, Supplier<? extends Collection<V>> factory) {
super(map);
this.factory = checkNotNull(factory);
}
@Override
Set<K> createKeySet() {
return createMaybeNavigableKeySet();
}
@Override
Map<K, Collection<V>> createAsMap() {
return createMaybeNavigableAsMap();
}
@Override
protected Collection<V> createCollection() {
return factory.get();
}
@Override
<E> Collection<E> unmodifiableCollectionSubclass(Collection<E> collection) {
if (collection instanceof NavigableSet) {
return Sets.unmodifiableNavigableSet((NavigableSet<E>) collection);
} else if (collection instanceof SortedSet) {
return Collections.unmodifiableSortedSet((SortedSet<E>) collection);
} else if (collection instanceof Set) {
return Collections.unmodifiableSet((Set<E>) collection);
} else if (collection instanceof List) {
return Collections.unmodifiableList((List<E>) collection);
} else {
return Collections.unmodifiableCollection(collection);
}
}
@Override
Collection<V> wrapCollection(K key, Collection<V> collection) {
if (collection instanceof List) {
return wrapList(key, (List<V>) collection, null);
} else if (collection instanceof NavigableSet) {
return new WrappedNavigableSet(key, (NavigableSet<V>) collection, null);
} else if (collection instanceof SortedSet) {
return new WrappedSortedSet(key, (SortedSet<V>) collection, null);
} else if (collection instanceof Set) {
return new WrappedSet(key, (Set<V>) collection);
} else {
return new WrappedCollection(key, collection, null);
}
}
// can't use Serialization writeMultimap and populateMultimap methods since
// there's no way to generate the empty backing map.
/** @serialData the factory and the backing map */
@GwtIncompatible // java.io.ObjectOutputStream
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
stream.writeObject(factory);
stream.writeObject(backingMap());
}
@GwtIncompatible // java.io.ObjectInputStream
@SuppressWarnings("unchecked") // reading data stored by writeObject
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
stream.defaultReadObject();
factory = (Supplier<? extends Collection<V>>) stream.readObject();
Map<K, Collection<V>> map = (Map<K, Collection<V>>) stream.readObject();
setMap(map);
}
@GwtIncompatible // java serialization not supported
private static final long serialVersionUID = 0;
}
/**
* Creates a new {@code ListMultimap} that uses the provided map and factory. It can generate a
* multimap based on arbitrary {@link Map} and {@link List} classes.
*
* <p>The {@code factory}-generated and {@code map} classes determine the multimap iteration
* order. They also specify the behavior of the {@code equals}, {@code hashCode}, and {@code
* toString} methods for the multimap and its returned views. The multimap's {@code get}, {@code
* removeAll}, and {@code replaceValues} methods return {@code RandomAccess} lists if the factory
* does. However, the multimap's {@code get} method returns instances of a different class than
* does {@code factory.get()}.
*
* <p>The multimap is serializable if {@code map}, {@code factory}, the lists generated by {@code
* factory}, and the multimap contents are all serializable.
*
* <p>The multimap is not threadsafe when any concurrent operations update the multimap, even if
* {@code map} and the instances generated by {@code factory} are. Concurrent read operations will
* work correctly. To allow concurrent update operations, wrap the multimap with a call to {@link
* #synchronizedListMultimap}.
*
* <p>Call this method only when the simpler methods {@link ArrayListMultimap#create()} and {@link
* LinkedListMultimap#create()} won't suffice.
*
* <p>Note: the multimap assumes complete ownership over of {@code map} and the lists returned by
* {@code factory}. Those objects should not be manually updated, they should be empty when
* provided, and they should not use soft, weak, or phantom references.
*
* @param map place to store the mapping from each key to its corresponding values
* @param factory supplier of new, empty lists that will each hold all values for a given key
* @throws IllegalArgumentException if {@code map} is not empty
*/
public static <K, V> ListMultimap<K, V> newListMultimap(
Map<K, Collection<V>> map, final Supplier<? extends List<V>> factory) {
return new CustomListMultimap<>(map, factory);
}
private static class CustomListMultimap<K, V> extends AbstractListMultimap<K, V> {
transient Supplier<? extends List<V>> factory;
CustomListMultimap(Map<K, Collection<V>> map, Supplier<? extends List<V>> factory) {
super(map);
this.factory = checkNotNull(factory);
}
@Override
Set<K> createKeySet() {
return createMaybeNavigableKeySet();
}
@Override
Map<K, Collection<V>> createAsMap() {
return createMaybeNavigableAsMap();
}
@Override
protected List<V> createCollection() {
return factory.get();
}
/** @serialData the factory and the backing map */
@GwtIncompatible // java.io.ObjectOutputStream
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
stream.writeObject(factory);
stream.writeObject(backingMap());
}
@GwtIncompatible // java.io.ObjectInputStream
@SuppressWarnings("unchecked") // reading data stored by writeObject
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
stream.defaultReadObject();
factory = (Supplier<? extends List<V>>) stream.readObject();
Map<K, Collection<V>> map = (Map<K, Collection<V>>) stream.readObject();
setMap(map);
}
@GwtIncompatible // java serialization not supported
private static final long serialVersionUID = 0;
}
/**
* Creates a new {@code SetMultimap} that uses the provided map and factory. It can generate a
* multimap based on arbitrary {@link Map} and {@link Set} classes.
*
* <p>The {@code factory}-generated and {@code map} classes determine the multimap iteration
* order. They also specify the behavior of the {@code equals}, {@code hashCode}, and {@code
* toString} methods for the multimap and its returned views. However, the multimap's {@code get}
* method returns instances of a different class than {@code factory.get()} does.
*
* <p>The multimap is serializable if {@code map}, {@code factory}, the sets generated by {@code
* factory}, and the multimap contents are all serializable.
*
* <p>The multimap is not threadsafe when any concurrent operations update the multimap, even if
* {@code map} and the instances generated by {@code factory} are. Concurrent read operations will
* work correctly. To allow concurrent update operations, wrap the multimap with a call to {@link
* #synchronizedSetMultimap}.
*
* <p>Call this method only when the simpler methods {@link HashMultimap#create()}, {@link
* LinkedHashMultimap#create()}, {@link TreeMultimap#create()}, and {@link
* TreeMultimap#create(Comparator, Comparator)} won't suffice.
*
* <p>Note: the multimap assumes complete ownership over of {@code map} and the sets returned by
* {@code factory}. Those objects should not be manually updated and they should not use soft,
* weak, or phantom references.
*
* @param map place to store the mapping from each key to its corresponding values
* @param factory supplier of new, empty sets that will each hold all values for a given key
* @throws IllegalArgumentException if {@code map} is not empty
*/
public static <K, V> SetMultimap<K, V> newSetMultimap(
Map<K, Collection<V>> map, final Supplier<? extends Set<V>> factory) {
return new CustomSetMultimap<>(map, factory);
}
private static class CustomSetMultimap<K, V> extends AbstractSetMultimap<K, V> {
transient Supplier<? extends Set<V>> factory;
CustomSetMultimap(Map<K, Collection<V>> map, Supplier<? extends Set<V>> factory) {
super(map);
this.factory = checkNotNull(factory);
}
@Override
Set<K> createKeySet() {
return createMaybeNavigableKeySet();
}
@Override
Map<K, Collection<V>> createAsMap() {
return createMaybeNavigableAsMap();
}
@Override
protected Set<V> createCollection() {
return factory.get();
}
@Override
<E> Collection<E> unmodifiableCollectionSubclass(Collection<E> collection) {
if (collection instanceof NavigableSet) {
return Sets.unmodifiableNavigableSet((NavigableSet<E>) collection);
} else if (collection instanceof SortedSet) {
return Collections.unmodifiableSortedSet((SortedSet<E>) collection);
} else {
return Collections.unmodifiableSet((Set<E>) collection);
}
}
@Override
Collection<V> wrapCollection(K key, Collection<V> collection) {
if (collection instanceof NavigableSet) {
return new WrappedNavigableSet(key, (NavigableSet<V>) collection, null);
} else if (collection instanceof SortedSet) {
return new WrappedSortedSet(key, (SortedSet<V>) collection, null);
} else {
return new WrappedSet(key, (Set<V>) collection);
}
}
/** @serialData the factory and the backing map */
@GwtIncompatible // java.io.ObjectOutputStream
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
stream.writeObject(factory);
stream.writeObject(backingMap());
}
@GwtIncompatible // java.io.ObjectInputStream
@SuppressWarnings("unchecked") // reading data stored by writeObject
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
stream.defaultReadObject();
factory = (Supplier<? extends Set<V>>) stream.readObject();
Map<K, Collection<V>> map = (Map<K, Collection<V>>) stream.readObject();
setMap(map);
}
@GwtIncompatible // not needed in emulated source
private static final long serialVersionUID = 0;
}
/**
* Creates a new {@code SortedSetMultimap} that uses the provided map and factory. It can generate
* a multimap based on arbitrary {@link Map} and {@link SortedSet} classes.
*
* <p>The {@code factory}-generated and {@code map} classes determine the multimap iteration
* order. They also specify the behavior of the {@code equals}, {@code hashCode}, and {@code
* toString} methods for the multimap and its returned views. However, the multimap's {@code get}
* method returns instances of a different class than {@code factory.get()} does.
*
* <p>The multimap is serializable if {@code map}, {@code factory}, the sets generated by {@code
* factory}, and the multimap contents are all serializable.
*
* <p>The multimap is not threadsafe when any concurrent operations update the multimap, even if
* {@code map} and the instances generated by {@code factory} are. Concurrent read operations will
* work correctly. To allow concurrent update operations, wrap the multimap with a call to {@link
* #synchronizedSortedSetMultimap}.
*
* <p>Call this method only when the simpler methods {@link TreeMultimap#create()} and {@link
* TreeMultimap#create(Comparator, Comparator)} won't suffice.
*
* <p>Note: the multimap assumes complete ownership over of {@code map} and the sets returned by
* {@code factory}. Those objects should not be manually updated and they should not use soft,
* weak, or phantom references.
*
* @param map place to store the mapping from each key to its corresponding values
* @param factory supplier of new, empty sorted sets that will each hold all values for a given
* key
* @throws IllegalArgumentException if {@code map} is not empty
*/
public static <K, V> SortedSetMultimap<K, V> newSortedSetMultimap(
Map<K, Collection<V>> map, final Supplier<? extends SortedSet<V>> factory) {
return new CustomSortedSetMultimap<>(map, factory);
}
private static class CustomSortedSetMultimap<K, V> extends AbstractSortedSetMultimap<K, V> {
transient Supplier<? extends SortedSet<V>> factory;
transient Comparator<? super V> valueComparator;
CustomSortedSetMultimap(Map<K, Collection<V>> map, Supplier<? extends SortedSet<V>> factory) {
super(map);
this.factory = checkNotNull(factory);
valueComparator = factory.get().comparator();
}
@Override
Set<K> createKeySet() {
return createMaybeNavigableKeySet();
}
@Override
Map<K, Collection<V>> createAsMap() {
return createMaybeNavigableAsMap();
}
@Override
protected SortedSet<V> createCollection() {
return factory.get();
}
@Override
public Comparator<? super V> valueComparator() {
return valueComparator;
}
/** @serialData the factory and the backing map */
@GwtIncompatible // java.io.ObjectOutputStream
private void writeObject(ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
stream.writeObject(factory);
stream.writeObject(backingMap());
}
@GwtIncompatible // java.io.ObjectInputStream
@SuppressWarnings("unchecked") // reading data stored by writeObject
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
stream.defaultReadObject();
factory = (Supplier<? extends SortedSet<V>>) stream.readObject();
valueComparator = factory.get().comparator();
Map<K, Collection<V>> map = (Map<K, Collection<V>>) stream.readObject();
setMap(map);
}
@GwtIncompatible // not needed in emulated source
private static final long serialVersionUID = 0;
}
/**
* Copies each key-value mapping in {@code source} into {@code dest}, with its key and value
* reversed.
*
* <p>If {@code source} is an {@link ImmutableMultimap}, consider using {@link
* ImmutableMultimap#inverse} instead.
*
* @param source any multimap
* @param dest the multimap to copy into; usually empty
* @return {@code dest}
*/
@CanIgnoreReturnValue
public static <K, V, M extends Multimap<K, V>> M invertFrom(
Multimap<? extends V, ? extends K> source, M dest) {
checkNotNull(dest);
for (Map.Entry<? extends V, ? extends K> entry : source.entries()) {
dest.put(entry.getValue(), entry.getKey());
}
return dest;
}
/**
* Returns a synchronized (thread-safe) multimap backed by the specified multimap. In order to
* guarantee serial access, it is critical that <b>all</b> access to the backing multimap is
* accomplished through the returned multimap.
*
* <p>It is imperative that the user manually synchronize on the returned multimap when accessing
* any of its collection views:
*
* <pre>{@code
* Multimap<K, V> multimap = Multimaps.synchronizedMultimap(
* HashMultimap.<K, V>create());
* ...
* Collection<V> values = multimap.get(key); // Needn't be in synchronized block
* ...
* synchronized (multimap) { // Synchronizing on multimap, not values!
* Iterator<V> i = values.iterator(); // Must be in synchronized block
* while (i.hasNext()) {
* foo(i.next());
* }
* }
* }</pre>
*
* <p>Failure to follow this advice may result in non-deterministic behavior.
*
* <p>Note that the generated multimap's {@link Multimap#removeAll} and {@link
* Multimap#replaceValues} methods return collections that aren't synchronized.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param multimap the multimap to be wrapped in a synchronized view
* @return a synchronized view of the specified multimap
*/
public static <K, V> Multimap<K, V> synchronizedMultimap(Multimap<K, V> multimap) {
return Synchronized.multimap(multimap, null);
}
/**
* Returns an unmodifiable view of the specified multimap. Query operations on the returned
* multimap "read through" to the specified multimap, and attempts to modify the returned
* multimap, either directly or through the multimap's views, result in an {@code
* UnsupportedOperationException}.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param delegate the multimap for which an unmodifiable view is to be returned
* @return an unmodifiable view of the specified multimap
*/
public static <K, V> Multimap<K, V> unmodifiableMultimap(Multimap<K, V> delegate) {
if (delegate instanceof UnmodifiableMultimap || delegate instanceof ImmutableMultimap) {
return delegate;
}
return new UnmodifiableMultimap<>(delegate);
}
/**
* Simply returns its argument.
*
* @deprecated no need to use this
* @since 10.0
*/
@Deprecated
public static <K, V> Multimap<K, V> unmodifiableMultimap(ImmutableMultimap<K, V> delegate) {
return checkNotNull(delegate);
}
private static class UnmodifiableMultimap<K, V> extends ForwardingMultimap<K, V>
implements Serializable {
final Multimap<K, V> delegate;
@LazyInit transient @Nullable Collection<Entry<K, V>> entries;
@LazyInit transient @Nullable Multiset<K> keys;
@LazyInit transient @Nullable Set<K> keySet;
@LazyInit transient @Nullable Collection<V> values;
@LazyInit transient @Nullable Map<K, Collection<V>> map;
UnmodifiableMultimap(final Multimap<K, V> delegate) {
this.delegate = checkNotNull(delegate);
}
@Override
protected Multimap<K, V> delegate() {
return delegate;
}
@Override
public void clear() {
throw new UnsupportedOperationException();
}
@Override
public Map<K, Collection<V>> asMap() {
Map<K, Collection<V>> result = map;
if (result == null) {
result =
map =
Collections.unmodifiableMap(
Maps.transformValues(
delegate.asMap(),
new Function<Collection<V>, Collection<V>>() {
@Override
public Collection<V> apply(Collection<V> collection) {
return unmodifiableValueCollection(collection);
}
}));
}
return result;
}
@Override
public Collection<Entry<K, V>> entries() {
Collection<Entry<K, V>> result = entries;
if (result == null) {
entries = result = unmodifiableEntries(delegate.entries());
}
return result;
}
@Override
public void forEach(BiConsumer<? super K, ? super V> consumer) {
delegate.forEach(checkNotNull(consumer));
}
@Override
public Collection<V> get(K key) {
return unmodifiableValueCollection(delegate.get(key));
}
@Override
public Multiset<K> keys() {
Multiset<K> result = keys;
if (result == null) {
keys = result = Multisets.unmodifiableMultiset(delegate.keys());
}
return result;
}
@Override
public Set<K> keySet() {
Set<K> result = keySet;
if (result == null) {
keySet = result = Collections.unmodifiableSet(delegate.keySet());
}
return result;
}
@Override
public boolean put(K key, V value) {
throw new UnsupportedOperationException();
}
@Override
public boolean putAll(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
@Override
public boolean putAll(Multimap<? extends K, ? extends V> multimap) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object key, Object value) {
throw new UnsupportedOperationException();
}
@Override
public Collection<V> removeAll(Object key) {
throw new UnsupportedOperationException();
}
@Override
public Collection<V> replaceValues(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
@Override
public Collection<V> values() {
Collection<V> result = values;
if (result == null) {
values = result = Collections.unmodifiableCollection(delegate.values());
}
return result;
}
private static final long serialVersionUID = 0;
}
private static class UnmodifiableListMultimap<K, V> extends UnmodifiableMultimap<K, V>
implements ListMultimap<K, V> {
UnmodifiableListMultimap(ListMultimap<K, V> delegate) {
super(delegate);
}
@Override
public ListMultimap<K, V> delegate() {
return (ListMultimap<K, V>) super.delegate();
}
@Override
public List<V> get(K key) {
return Collections.unmodifiableList(delegate().get(key));
}
@Override
public List<V> removeAll(Object key) {
throw new UnsupportedOperationException();
}
@Override
public List<V> replaceValues(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
private static final long serialVersionUID = 0;
}
private static class UnmodifiableSetMultimap<K, V> extends UnmodifiableMultimap<K, V>
implements SetMultimap<K, V> {
UnmodifiableSetMultimap(SetMultimap<K, V> delegate) {
super(delegate);
}
@Override
public SetMultimap<K, V> delegate() {
return (SetMultimap<K, V>) super.delegate();
}
@Override
public Set<V> get(K key) {
/*
* Note that this doesn't return a SortedSet when delegate is a
* SortedSetMultiset, unlike (SortedSet<V>) super.get().
*/
return Collections.unmodifiableSet(delegate().get(key));
}
@Override
public Set<Map.Entry<K, V>> entries() {
return Maps.unmodifiableEntrySet(delegate().entries());
}
@Override
public Set<V> removeAll(Object key) {
throw new UnsupportedOperationException();
}
@Override
public Set<V> replaceValues(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
private static final long serialVersionUID = 0;
}
private static class UnmodifiableSortedSetMultimap<K, V> extends UnmodifiableSetMultimap<K, V>
implements SortedSetMultimap<K, V> {
UnmodifiableSortedSetMultimap(SortedSetMultimap<K, V> delegate) {
super(delegate);
}
@Override
public SortedSetMultimap<K, V> delegate() {
return (SortedSetMultimap<K, V>) super.delegate();
}
@Override
public SortedSet<V> get(K key) {
return Collections.unmodifiableSortedSet(delegate().get(key));
}
@Override
public SortedSet<V> removeAll(Object key) {
throw new UnsupportedOperationException();
}
@Override
public SortedSet<V> replaceValues(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
@Override
public Comparator<? super V> valueComparator() {
return delegate().valueComparator();
}
private static final long serialVersionUID = 0;
}
/**
* Returns a synchronized (thread-safe) {@code SetMultimap} backed by the specified multimap.
*
* <p>You must follow the warnings described in {@link #synchronizedMultimap}.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param multimap the multimap to be wrapped
* @return a synchronized view of the specified multimap
*/
public static <K, V> SetMultimap<K, V> synchronizedSetMultimap(SetMultimap<K, V> multimap) {
return Synchronized.setMultimap(multimap, null);
}
/**
* Returns an unmodifiable view of the specified {@code SetMultimap}. Query operations on the
* returned multimap "read through" to the specified multimap, and attempts to modify the returned
* multimap, either directly or through the multimap's views, result in an {@code
* UnsupportedOperationException}.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param delegate the multimap for which an unmodifiable view is to be returned
* @return an unmodifiable view of the specified multimap
*/
public static <K, V> SetMultimap<K, V> unmodifiableSetMultimap(SetMultimap<K, V> delegate) {
if (delegate instanceof UnmodifiableSetMultimap || delegate instanceof ImmutableSetMultimap) {
return delegate;
}
return new UnmodifiableSetMultimap<>(delegate);
}
/**
* Simply returns its argument.
*
* @deprecated no need to use this
* @since 10.0
*/
@Deprecated
public static <K, V> SetMultimap<K, V> unmodifiableSetMultimap(
ImmutableSetMultimap<K, V> delegate) {
return checkNotNull(delegate);
}
/**
* Returns a synchronized (thread-safe) {@code SortedSetMultimap} backed by the specified
* multimap.
*
* <p>You must follow the warnings described in {@link #synchronizedMultimap}.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param multimap the multimap to be wrapped
* @return a synchronized view of the specified multimap
*/
public static <K, V> SortedSetMultimap<K, V> synchronizedSortedSetMultimap(
SortedSetMultimap<K, V> multimap) {
return Synchronized.sortedSetMultimap(multimap, null);
}
/**
* Returns an unmodifiable view of the specified {@code SortedSetMultimap}. Query operations on
* the returned multimap "read through" to the specified multimap, and attempts to modify the
* returned multimap, either directly or through the multimap's views, result in an {@code
* UnsupportedOperationException}.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param delegate the multimap for which an unmodifiable view is to be returned
* @return an unmodifiable view of the specified multimap
*/
public static <K, V> SortedSetMultimap<K, V> unmodifiableSortedSetMultimap(
SortedSetMultimap<K, V> delegate) {
if (delegate instanceof UnmodifiableSortedSetMultimap) {
return delegate;
}
return new UnmodifiableSortedSetMultimap<>(delegate);
}
/**
* Returns a synchronized (thread-safe) {@code ListMultimap} backed by the specified multimap.
*
* <p>You must follow the warnings described in {@link #synchronizedMultimap}.
*
* @param multimap the multimap to be wrapped
* @return a synchronized view of the specified multimap
*/
public static <K, V> ListMultimap<K, V> synchronizedListMultimap(ListMultimap<K, V> multimap) {
return Synchronized.listMultimap(multimap, null);
}
/**
* Returns an unmodifiable view of the specified {@code ListMultimap}. Query operations on the
* returned multimap "read through" to the specified multimap, and attempts to modify the returned
* multimap, either directly or through the multimap's views, result in an {@code
* UnsupportedOperationException}.
*
* <p>The returned multimap will be serializable if the specified multimap is serializable.
*
* @param delegate the multimap for which an unmodifiable view is to be returned
* @return an unmodifiable view of the specified multimap
*/
public static <K, V> ListMultimap<K, V> unmodifiableListMultimap(ListMultimap<K, V> delegate) {
if (delegate instanceof UnmodifiableListMultimap || delegate instanceof ImmutableListMultimap) {
return delegate;
}
return new UnmodifiableListMultimap<>(delegate);
}
/**
* Simply returns its argument.
*
* @deprecated no need to use this
* @since 10.0
*/
@Deprecated
public static <K, V> ListMultimap<K, V> unmodifiableListMultimap(
ImmutableListMultimap<K, V> delegate) {
return checkNotNull(delegate);
}
/**
* Returns an unmodifiable view of the specified collection, preserving the interface for
* instances of {@code SortedSet}, {@code Set}, {@code List} and {@code Collection}, in that order
* of preference.
*
* @param collection the collection for which to return an unmodifiable view
* @return an unmodifiable view of the collection
*/
private static <V> Collection<V> unmodifiableValueCollection(Collection<V> collection) {
if (collection instanceof SortedSet) {
return Collections.unmodifiableSortedSet((SortedSet<V>) collection);
} else if (collection instanceof Set) {
return Collections.unmodifiableSet((Set<V>) collection);
} else if (collection instanceof List) {
return Collections.unmodifiableList((List<V>) collection);
}
return Collections.unmodifiableCollection(collection);
}
/**
* Returns an unmodifiable view of the specified collection of entries. The {@link Entry#setValue}
* operation throws an {@link UnsupportedOperationException}. If the specified collection is a
* {@code Set}, the returned collection is also a {@code Set}.
*
* @param entries the entries for which to return an unmodifiable view
* @return an unmodifiable view of the entries
*/
private static <K, V> Collection<Entry<K, V>> unmodifiableEntries(
Collection<Entry<K, V>> entries) {
if (entries instanceof Set) {
return Maps.unmodifiableEntrySet((Set<Entry<K, V>>) entries);
}
return new Maps.UnmodifiableEntries<>(Collections.unmodifiableCollection(entries));
}
/**
* Returns {@link ListMultimap#asMap multimap.asMap()}, with its type corrected from {@code Map<K,
* Collection<V>>} to {@code Map<K, List<V>>}.
*
* @since 15.0
*/
@Beta
@SuppressWarnings("unchecked")
// safe by specification of ListMultimap.asMap()
public static <K, V> Map<K, List<V>> asMap(ListMultimap<K, V> multimap) {
return (Map<K, List<V>>) (Map<K, ?>) multimap.asMap();
}
/**
* Returns {@link SetMultimap#asMap multimap.asMap()}, with its type corrected from {@code Map<K,
* Collection<V>>} to {@code Map<K, Set<V>>}.
*
* @since 15.0
*/
@Beta
@SuppressWarnings("unchecked")
// safe by specification of SetMultimap.asMap()
public static <K, V> Map<K, Set<V>> asMap(SetMultimap<K, V> multimap) {
return (Map<K, Set<V>>) (Map<K, ?>) multimap.asMap();
}
/**
* Returns {@link SortedSetMultimap#asMap multimap.asMap()}, with its type corrected from {@code
* Map<K, Collection<V>>} to {@code Map<K, SortedSet<V>>}.
*
* @since 15.0
*/
@Beta
@SuppressWarnings("unchecked")
// safe by specification of SortedSetMultimap.asMap()
public static <K, V> Map<K, SortedSet<V>> asMap(SortedSetMultimap<K, V> multimap) {
return (Map<K, SortedSet<V>>) (Map<K, ?>) multimap.asMap();
}
/**
* Returns {@link Multimap#asMap multimap.asMap()}. This is provided for parity with the other
* more strongly-typed {@code asMap()} implementations.
*
* @since 15.0
*/
@Beta
public static <K, V> Map<K, Collection<V>> asMap(Multimap<K, V> multimap) {
return multimap.asMap();
}
/**
* Returns a multimap view of the specified map. The multimap is backed by the map, so changes to
* the map are reflected in the multimap, and vice versa. If the map is modified while an
* iteration over one of the multimap's collection views is in progress (except through the
* iterator's own {@code remove} operation, or through the {@code setValue} operation on a map
* entry returned by the iterator), the results of the iteration are undefined.
*
* <p>The multimap supports mapping removal, which removes the corresponding mapping from the map.
* It does not support any operations which might add mappings, such as {@code put}, {@code
* putAll} or {@code replaceValues}.
*
* <p>The returned multimap will be serializable if the specified map is serializable.
*
* @param map the backing map for the returned multimap view
*/
public static <K, V> SetMultimap<K, V> forMap(Map<K, V> map) {
return new MapMultimap<>(map);
}
/** @see Multimaps#forMap */
private static class MapMultimap<K, V> extends AbstractMultimap<K, V>
implements SetMultimap<K, V>, Serializable {
final Map<K, V> map;
MapMultimap(Map<K, V> map) {
this.map = checkNotNull(map);
}
@Override
public int size() {
return map.size();
}
@Override
public boolean containsKey(Object key) {
return map.containsKey(key);
}
@Override
public boolean containsValue(Object value) {
return map.containsValue(value);
}
@Override
public boolean containsEntry(Object key, Object value) {
return map.entrySet().contains(Maps.immutableEntry(key, value));
}
@Override
public Set<V> get(final K key) {
return new Sets.ImprovedAbstractSet<V>() {
@Override
public Iterator<V> iterator() {
return new Iterator<V>() {
int i;
@Override
public boolean hasNext() {
return (i == 0) && map.containsKey(key);
}
@Override
public V next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
i++;
return map.get(key);
}
@Override
public void remove() {
checkRemove(i == 1);
i = -1;
map.remove(key);
}
};
}
@Override
public int size() {
return map.containsKey(key) ? 1 : 0;
}
};
}
@Override
public boolean put(K key, V value) {
throw new UnsupportedOperationException();
}
@Override
public boolean putAll(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
@Override
public boolean putAll(Multimap<? extends K, ? extends V> multimap) {
throw new UnsupportedOperationException();
}
@Override
public Set<V> replaceValues(K key, Iterable<? extends V> values) {
throw new UnsupportedOperationException();
}
@Override
public boolean remove(Object key, Object value) {
return map.entrySet().remove(Maps.immutableEntry(key, value));
}
@Override
public Set<V> removeAll(Object key) {
Set<V> values = new HashSet<V>(2);
if (!map.containsKey(key)) {
return values;
}
values.add(map.remove(key));
return values;
}
@Override
public void clear() {
map.clear();
}
@Override
Set<K> createKeySet() {
return map.keySet();
}
@Override
Collection<V> createValues() {
return map.values();
}
@Override
public Set<Entry<K, V>> entries() {
return map.entrySet();
}
@Override
Collection<Entry<K, V>> createEntries() {
throw new AssertionError("unreachable");
}
@Override
Multiset<K> createKeys() {
return new Multimaps.Keys<K, V>(this);
}
@Override
Iterator<Entry<K, V>> entryIterator() {
return map.entrySet().iterator();
}
@Override
Map<K, Collection<V>> createAsMap() {
return new AsMap<>(this);
}
@Override
public int hashCode() {
return map.hashCode();
}
private static final long serialVersionUID = 7845222491160860175L;
}
/**
* Returns a view of a multimap where each value is transformed by a function. All other
* properties of the multimap, such as iteration order, are left intact. For example, the code:
*
* <pre>{@code
* Multimap<String, Integer> multimap =
* ImmutableSetMultimap.of("a", 2, "b", -3, "b", -3, "a", 4, "c", 6);
* Function<Integer, String> square = new Function<Integer, String>() {
* public String apply(Integer in) {
* return Integer.toString(in * in);
* }
* };
* Multimap<String, String> transformed =
* Multimaps.transformValues(multimap, square);
* System.out.println(transformed);
* }</pre>
*
* ... prints {@code {a=[4, 16], b=[9, 9], c=[36]}}.
*
* <p>Changes in the underlying multimap are reflected in this view. Conversely, this view
* supports removal operations, and these are reflected in the underlying multimap.
*
* <p>It's acceptable for the underlying multimap to contain null keys, and even null values
* provided that the function is capable of accepting null input. The transformed multimap might
* contain null values, if the function sometimes gives a null result.
*
* <p>The returned multimap is not thread-safe or serializable, even if the underlying multimap
* is. The {@code equals} and {@code hashCode} methods of the returned multimap are meaningless,
* since there is not a definition of {@code equals} or {@code hashCode} for general collections,
* and {@code get()} will return a general {@code Collection} as opposed to a {@code List} or a
* {@code Set}.
*
* <p>The function is applied lazily, invoked when needed. This is necessary for the returned
* multimap to be a view, but it means that the function will be applied many times for bulk
* operations like {@link Multimap#containsValue} and {@code Multimap.toString()}. For this to
* perform well, {@code function} should be fast. To avoid lazy evaluation when the returned
* multimap doesn't need to be a view, copy the returned multimap into a new multimap of your
* choosing.
*
* @since 7.0
*/
public static <K, V1, V2> Multimap<K, V2> transformValues(
Multimap<K, V1> fromMultimap, final Function<? super V1, V2> function) {
checkNotNull(function);
EntryTransformer<K, V1, V2> transformer = Maps.asEntryTransformer(function);
return transformEntries(fromMultimap, transformer);
}
/**
* Returns a view of a {@code ListMultimap} where each value is transformed by a function. All
* other properties of the multimap, such as iteration order, are left intact. For example, the
* code:
*
* <pre>{@code
* ListMultimap<String, Integer> multimap
* = ImmutableListMultimap.of("a", 4, "a", 16, "b", 9);
* Function<Integer, Double> sqrt =
* new Function<Integer, Double>() {
* public Double apply(Integer in) {
* return Math.sqrt((int) in);
* }
* };
* ListMultimap<String, Double> transformed = Multimaps.transformValues(map,
* sqrt);
* System.out.println(transformed);
* }</pre>
*
* ... prints {@code {a=[2.0, 4.0], b=[3.0]}}.
*
* <p>Changes in the underlying multimap are reflected in this view. Conversely, this view
* supports removal operations, and these are reflected in the underlying multimap.
*
* <p>It's acceptable for the underlying multimap to contain null keys, and even null values
* provided that the function is capable of accepting null input. The transformed multimap might
* contain null values, if the function sometimes gives a null result.
*
* <p>The returned multimap is not thread-safe or serializable, even if the underlying multimap
* is.
*
* <p>The function is applied lazily, invoked when needed. This is necessary for the returned
* multimap to be a view, but it means that the function will be applied many times for bulk
* operations like {@link Multimap#containsValue} and {@code Multimap.toString()}. For this to
* perform well, {@code function} should be fast. To avoid lazy evaluation when the returned
* multimap doesn't need to be a view, copy the returned multimap into a new multimap of your
* choosing.
*
* @since 7.0
*/
public static <K, V1, V2> ListMultimap<K, V2> transformValues(
ListMultimap<K, V1> fromMultimap, final Function<? super V1, V2> function) {
checkNotNull(function);
EntryTransformer<K, V1, V2> transformer = Maps.asEntryTransformer(function);
return transformEntries(fromMultimap, transformer);
}
/**
* Returns a view of a multimap whose values are derived from the original multimap's entries. In
* contrast to {@link #transformValues}, this method's entry-transformation logic may depend on
* the key as well as the value.
*
* <p>All other properties of the transformed multimap, such as iteration order, are left intact.
* For example, the code:
*
* <pre>{@code
* SetMultimap<String, Integer> multimap =
* ImmutableSetMultimap.of("a", 1, "a", 4, "b", -6);
* EntryTransformer<String, Integer, String> transformer =
* new EntryTransformer<String, Integer, String>() {
* public String transformEntry(String key, Integer value) {
* return (value >= 0) ? key : "no" + key;
* }
* };
* Multimap<String, String> transformed =
* Multimaps.transformEntries(multimap, transformer);
* System.out.println(transformed);
* }</pre>
*
* ... prints {@code {a=[a, a], b=[nob]}}.
*
* <p>Changes in the underlying multimap are reflected in this view. Conversely, this view
* supports removal operations, and these are reflected in the underlying multimap.
*
* <p>It's acceptable for the underlying multimap to contain null keys and null values provided
* that the transformer is capable of accepting null inputs. The transformed multimap might
* contain null values if the transformer sometimes gives a null result.
*
* <p>The returned multimap is not thread-safe or serializable, even if the underlying multimap
* is. The {@code equals} and {@code hashCode} methods of the returned multimap are meaningless,
* since there is not a definition of {@code equals} or {@code hashCode} for general collections,
* and {@code get()} will return a general {@code Collection} as opposed to a {@code List} or a
* {@code Set}.
*
* <p>The transformer is applied lazily, invoked when needed. This is necessary for the returned
* multimap to be a view, but it means that the transformer will be applied many times for bulk
* operations like {@link Multimap#containsValue} and {@link Object#toString}. For this to perform
* well, {@code transformer} should be fast. To avoid lazy evaluation when the returned multimap
* doesn't need to be a view, copy the returned multimap into a new multimap of your choosing.
*
* <p><b>Warning:</b> This method assumes that for any instance {@code k} of {@code
* EntryTransformer} key type {@code K}, {@code k.equals(k2)} implies that {@code k2} is also of
* type {@code K}. Using an {@code EntryTransformer} key type for which this may not hold, such as
* {@code ArrayList}, may risk a {@code ClassCastException} when calling methods on the
* transformed multimap.
*
* @since 7.0
*/
public static <K, V1, V2> Multimap<K, V2> transformEntries(
Multimap<K, V1> fromMap, EntryTransformer<? super K, ? super V1, V2> transformer) {
return new TransformedEntriesMultimap<>(fromMap, transformer);
}
/**
* Returns a view of a {@code ListMultimap} whose values are derived from the original multimap's
* entries. In contrast to {@link #transformValues(ListMultimap, Function)}, this method's
* entry-transformation logic may depend on the key as well as the value.
*
* <p>All other properties of the transformed multimap, such as iteration order, are left intact.
* For example, the code:
*
* <pre>{@code
* Multimap<String, Integer> multimap =
* ImmutableMultimap.of("a", 1, "a", 4, "b", 6);
* EntryTransformer<String, Integer, String> transformer =
* new EntryTransformer<String, Integer, String>() {
* public String transformEntry(String key, Integer value) {
* return key + value;
* }
* };
* Multimap<String, String> transformed =
* Multimaps.transformEntries(multimap, transformer);
* System.out.println(transformed);
* }</pre>
*
* ... prints {@code {"a"=["a1", "a4"], "b"=["b6"]}}.
*
* <p>Changes in the underlying multimap are reflected in this view. Conversely, this view
* supports removal operations, and these are reflected in the underlying multimap.
*
* <p>It's acceptable for the underlying multimap to contain null keys and null values provided
* that the transformer is capable of accepting null inputs. The transformed multimap might
* contain null values if the transformer sometimes gives a null result.
*
* <p>The returned multimap is not thread-safe or serializable, even if the underlying multimap
* is.
*
* <p>The transformer is applied lazily, invoked when needed. This is necessary for the returned
* multimap to be a view, but it means that the transformer will be applied many times for bulk
* operations like {@link Multimap#containsValue} and {@link Object#toString}. For this to perform
* well, {@code transformer} should be fast. To avoid lazy evaluation when the returned multimap
* doesn't need to be a view, copy the returned multimap into a new multimap of your choosing.
*
* <p><b>Warning:</b> This method assumes that for any instance {@code k} of {@code
* EntryTransformer} key type {@code K}, {@code k.equals(k2)} implies that {@code k2} is also of
* type {@code K}. Using an {@code EntryTransformer} key type for which this may not hold, such as
* {@code ArrayList}, may risk a {@code ClassCastException} when calling methods on the
* transformed multimap.
*
* @since 7.0
*/
public static <K, V1, V2> ListMultimap<K, V2> transformEntries(
ListMultimap<K, V1> fromMap, EntryTransformer<? super K, ? super V1, V2> transformer) {
return new TransformedEntriesListMultimap<>(fromMap, transformer);
}
private static class TransformedEntriesMultimap<K, V1, V2> extends AbstractMultimap<K, V2> {
final Multimap<K, V1> fromMultimap;
final EntryTransformer<? super K, ? super V1, V2> transformer;
TransformedEntriesMultimap(
Multimap<K, V1> fromMultimap,
final EntryTransformer<? super K, ? super V1, V2> transformer) {
this.fromMultimap = checkNotNull(fromMultimap);
this.transformer = checkNotNull(transformer);
}
Collection<V2> transform(K key, Collection<V1> values) {
Function<? super V1, V2> function = Maps.asValueToValueFunction(transformer, key);
if (values instanceof List) {
return Lists.transform((List<V1>) values, function);
} else {
return Collections2.transform(values, function);
}
}
@Override
Map<K, Collection<V2>> createAsMap() {
return Maps.transformEntries(
fromMultimap.asMap(),
new EntryTransformer<K, Collection<V1>, Collection<V2>>() {
@Override
public Collection<V2> transformEntry(K key, Collection<V1> value) {
return transform(key, value);
}
});
}
@Override
public void clear() {
fromMultimap.clear();
}
@Override
public boolean containsKey(Object key) {
return fromMultimap.containsKey(key);
}
@Override
Collection<Entry<K, V2>> createEntries() {
return new Entries();
}
@Override
Iterator<Entry<K, V2>> entryIterator() {
return Iterators.transform(
fromMultimap.entries().iterator(), Maps.<K, V1, V2>asEntryToEntryFunction(transformer));
}
@Override
public Collection<V2> get(final K key) {
return transform(key, fromMultimap.get(key));
}
@Override
public boolean isEmpty() {
return fromMultimap.isEmpty();
}
@Override
Set<K> createKeySet() {
return fromMultimap.keySet();
}
@Override
Multiset<K> createKeys() {
return fromMultimap.keys();
}
@Override
public boolean put(K key, V2 value) {
throw new UnsupportedOperationException();
}
@Override
public boolean putAll(K key, Iterable<? extends V2> values) {
throw new UnsupportedOperationException();
}
@Override
public boolean putAll(Multimap<? extends K, ? extends V2> multimap) {
throw new UnsupportedOperationException();
}
@SuppressWarnings("unchecked")
@Override
public boolean remove(Object key, Object value) {
return get((K) key).remove(value);
}
@SuppressWarnings("unchecked")
@Override
public Collection<V2> removeAll(Object key) {
return transform((K) key, fromMultimap.removeAll(key));
}
@Override
public Collection<V2> replaceValues(K key, Iterable<? extends V2> values) {
throw new UnsupportedOperationException();
}
@Override
public int size() {
return fromMultimap.size();
}
@Override
Collection<V2> createValues() {
return Collections2.transform(
fromMultimap.entries(), Maps.<K, V1, V2>asEntryToValueFunction(transformer));
}
}
private static final class TransformedEntriesListMultimap<K, V1, V2>
extends TransformedEntriesMultimap<K, V1, V2> implements ListMultimap<K, V2> {
TransformedEntriesListMultimap(
ListMultimap<K, V1> fromMultimap, EntryTransformer<? super K, ? super V1, V2> transformer) {
super(fromMultimap, transformer);
}
@Override
List<V2> transform(K key, Collection<V1> values) {
return Lists.transform((List<V1>) values, Maps.asValueToValueFunction(transformer, key));
}
@Override
public List<V2> get(K key) {
return transform(key, fromMultimap.get(key));
}
@SuppressWarnings("unchecked")
@Override
public List<V2> removeAll(Object key) {
return transform((K) key, fromMultimap.removeAll(key));
}
@Override
public List<V2> replaceValues(K key, Iterable<? extends V2> values) {
throw new UnsupportedOperationException();
}
}
/**
* Creates an index {@code ImmutableListMultimap} that contains the results of applying a
* specified function to each item in an {@code Iterable} of values. Each value will be stored as
* a value in the resulting multimap, yielding a multimap with the same size as the input
* iterable. The key used to store that value in the multimap will be the result of calling the
* function on that value. The resulting multimap is created as an immutable snapshot. In the
* returned multimap, keys appear in the order they are first encountered, and the values
* corresponding to each key appear in the same order as they are encountered.
*
* <p>For example,
*
* <pre>{@code
* List<String> badGuys =
* Arrays.asList("Inky", "Blinky", "Pinky", "Pinky", "Clyde");
* Function<String, Integer> stringLengthFunction = ...;
* Multimap<Integer, String> index =
* Multimaps.index(badGuys, stringLengthFunction);
* System.out.println(index);
* }</pre>
*
* <p>prints
*
* <pre>{@code
* {4=[Inky], 6=[Blinky], 5=[Pinky, Pinky, Clyde]}
* }</pre>
*
* <p>The returned multimap is serializable if its keys and values are all serializable.
*
* @param values the values to use when constructing the {@code ImmutableListMultimap}
* @param keyFunction the function used to produce the key for each value
* @return {@code ImmutableListMultimap} mapping the result of evaluating the function {@code
* keyFunction} on each value in the input collection to that value
* @throws NullPointerException if any element of {@code values} is {@code null}, or if {@code
* keyFunction} produces {@code null} for any key
*/
public static <K, V> ImmutableListMultimap<K, V> index(
Iterable<V> values, Function<? super V, K> keyFunction) {
return index(values.iterator(), keyFunction);
}
/**
* Creates an index {@code ImmutableListMultimap} that contains the results of applying a
* specified function to each item in an {@code Iterator} of values. Each value will be stored as
* a value in the resulting multimap, yielding a multimap with the same size as the input
* iterator. The key used to store that value in the multimap will be the result of calling the
* function on that value. The resulting multimap is created as an immutable snapshot. In the
* returned multimap, keys appear in the order they are first encountered, and the values
* corresponding to each key appear in the same order as they are encountered.
*
* <p>For example,
*
* <pre>{@code
* List<String> badGuys =
* Arrays.asList("Inky", "Blinky", "Pinky", "Pinky", "Clyde");
* Function<String, Integer> stringLengthFunction = ...;
* Multimap<Integer, String> index =
* Multimaps.index(badGuys.iterator(), stringLengthFunction);
* System.out.println(index);
* }</pre>
*
* <p>prints
*
* <pre>{@code
* {4=[Inky], 6=[Blinky], 5=[Pinky, Pinky, Clyde]}
* }</pre>
*
* <p>The returned multimap is serializable if its keys and values are all serializable.
*
* @param values the values to use when constructing the {@code ImmutableListMultimap}
* @param keyFunction the function used to produce the key for each value
* @return {@code ImmutableListMultimap} mapping the result of evaluating the function {@code
* keyFunction} on each value in the input collection to that value
* @throws NullPointerException if any element of {@code values} is {@code null}, or if {@code
* keyFunction} produces {@code null} for any key
* @since 10.0
*/
public static <K, V> ImmutableListMultimap<K, V> index(
Iterator<V> values, Function<? super V, K> keyFunction) {
checkNotNull(keyFunction);
ImmutableListMultimap.Builder<K, V> builder = ImmutableListMultimap.builder();
while (values.hasNext()) {
V value = values.next();
checkNotNull(value, values);
builder.put(keyFunction.apply(value), value);
}
return builder.build();
}
static class Keys<K, V> extends AbstractMultiset<K> {
@Weak final Multimap<K, V> multimap;
Keys(Multimap<K, V> multimap) {
this.multimap = multimap;
}
@Override
Iterator<Multiset.Entry<K>> entryIterator() {
return new TransformedIterator<Map.Entry<K, Collection<V>>, Multiset.Entry<K>>(
multimap.asMap().entrySet().iterator()) {
@Override
Multiset.Entry<K> transform(final Map.Entry<K, Collection<V>> backingEntry) {
return new Multisets.AbstractEntry<K>() {
@Override
public K getElement() {
return backingEntry.getKey();
}
@Override
public int getCount() {
return backingEntry.getValue().size();
}
};
}
};
}
@Override
public Spliterator<K> spliterator() {
return CollectSpliterators.map(multimap.entries().spliterator(), Map.Entry::getKey);
}
@Override
public void forEach(Consumer<? super K> consumer) {
checkNotNull(consumer);
multimap.entries().forEach(entry -> consumer.accept(entry.getKey()));
}
@Override
int distinctElements() {
return multimap.asMap().size();
}
@Override
public int size() {
return multimap.size();
}
@Override
public boolean contains(@Nullable Object element) {
return multimap.containsKey(element);
}
@Override
public Iterator<K> iterator() {
return Maps.keyIterator(multimap.entries().iterator());
}
@Override
public int count(@Nullable Object element) {
Collection<V> values = Maps.safeGet(multimap.asMap(), element);
return (values == null) ? 0 : values.size();
}
@Override
public int remove(@Nullable Object element, int occurrences) {
checkNonnegative(occurrences, "occurrences");
if (occurrences == 0) {
return count(element);
}
Collection<V> values = Maps.safeGet(multimap.asMap(), element);
if (values == null) {
return 0;
}
int oldCount = values.size();
if (occurrences >= oldCount) {
values.clear();
} else {
Iterator<V> iterator = values.iterator();
for (int i = 0; i < occurrences; i++) {
iterator.next();
iterator.remove();
}
}
return oldCount;
}
@Override
public void clear() {
multimap.clear();
}
@Override
public Set<K> elementSet() {
return multimap.keySet();
}
@Override
Iterator<K> elementIterator() {
throw new AssertionError("should never be called");
}
}
/** A skeleton implementation of {@link Multimap#entries()}. */
abstract static class Entries<K, V> extends AbstractCollection<Map.Entry<K, V>> {
abstract Multimap<K, V> multimap();
@Override
public int size() {
return multimap().size();
}
@Override
public boolean contains(@Nullable Object o) {
if (o instanceof Map.Entry) {
Map.Entry<?, ?> entry = (Map.Entry<?, ?>) o;
return multimap().containsEntry(entry.getKey(), entry.getValue());
}
return false;
}
@Override
public boolean remove(@Nullable Object o) {
if (o instanceof Map.Entry) {
Map.Entry<?, ?> entry = (Map.Entry<?, ?>) o;
return multimap().remove(entry.getKey(), entry.getValue());
}
return false;
}
@Override
public void clear() {
multimap().clear();
}
}
/** A skeleton implementation of {@link Multimap#asMap()}. */
static final class AsMap<K, V> extends Maps.ViewCachingAbstractMap<K, Collection<V>> {
@Weak private final Multimap<K, V> multimap;
AsMap(Multimap<K, V> multimap) {
this.multimap = checkNotNull(multimap);
}
@Override
public int size() {
return multimap.keySet().size();
}
@Override
protected Set<Entry<K, Collection<V>>> createEntrySet() {
return new EntrySet();
}
void removeValuesForKey(Object key) {
multimap.keySet().remove(key);
}
@WeakOuter
class EntrySet extends Maps.EntrySet<K, Collection<V>> {
@Override
Map<K, Collection<V>> map() {
return AsMap.this;
}
@Override
public Iterator<Entry<K, Collection<V>>> iterator() {
return Maps.asMapEntryIterator(
multimap.keySet(),
new Function<K, Collection<V>>() {
@Override
public Collection<V> apply(K key) {
return multimap.get(key);
}
});
}
@Override
public boolean remove(Object o) {
if (!contains(o)) {
return false;
}
Map.Entry<?, ?> entry = (Map.Entry<?, ?>) o;
removeValuesForKey(entry.getKey());
return true;
}
}
@SuppressWarnings("unchecked")
@Override
public Collection<V> get(Object key) {
return containsKey(key) ? multimap.get((K) key) : null;
}
@Override
public Collection<V> remove(Object key) {
return containsKey(key) ? multimap.removeAll(key) : null;
}
@Override
public Set<K> keySet() {
return multimap.keySet();
}
@Override
public boolean isEmpty() {
return multimap.isEmpty();
}
@Override
public boolean containsKey(Object key) {
return multimap.containsKey(key);
}
@Override
public void clear() {
multimap.clear();
}
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} whose keys satisfy a
* predicate. The returned multimap is a live view of {@code unfiltered}; changes to one affect
* the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a key that doesn't
* satisfy the predicate, the multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose keys satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code keyPredicate} must be <i>consistent with equals</i>, as documented at
* {@link Predicate#apply}. Do not provide a predicate such as {@code
* Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals.
*
* @since 11.0
*/
public static <K, V> Multimap<K, V> filterKeys(
Multimap<K, V> unfiltered, final Predicate<? super K> keyPredicate) {
if (unfiltered instanceof SetMultimap) {
return filterKeys((SetMultimap<K, V>) unfiltered, keyPredicate);
} else if (unfiltered instanceof ListMultimap) {
return filterKeys((ListMultimap<K, V>) unfiltered, keyPredicate);
} else if (unfiltered instanceof FilteredKeyMultimap) {
FilteredKeyMultimap<K, V> prev = (FilteredKeyMultimap<K, V>) unfiltered;
return new FilteredKeyMultimap<>(
prev.unfiltered, Predicates.<K>and(prev.keyPredicate, keyPredicate));
} else if (unfiltered instanceof FilteredMultimap) {
FilteredMultimap<K, V> prev = (FilteredMultimap<K, V>) unfiltered;
return filterFiltered(prev, Maps.<K>keyPredicateOnEntries(keyPredicate));
} else {
return new FilteredKeyMultimap<>(unfiltered, keyPredicate);
}
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} whose keys satisfy a
* predicate. The returned multimap is a live view of {@code unfiltered}; changes to one affect
* the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a key that doesn't
* satisfy the predicate, the multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose keys satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code keyPredicate} must be <i>consistent with equals</i>, as documented at
* {@link Predicate#apply}. Do not provide a predicate such as {@code
* Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals.
*
* @since 14.0
*/
public static <K, V> SetMultimap<K, V> filterKeys(
SetMultimap<K, V> unfiltered, final Predicate<? super K> keyPredicate) {
if (unfiltered instanceof FilteredKeySetMultimap) {
FilteredKeySetMultimap<K, V> prev = (FilteredKeySetMultimap<K, V>) unfiltered;
return new FilteredKeySetMultimap<>(
prev.unfiltered(), Predicates.<K>and(prev.keyPredicate, keyPredicate));
} else if (unfiltered instanceof FilteredSetMultimap) {
FilteredSetMultimap<K, V> prev = (FilteredSetMultimap<K, V>) unfiltered;
return filterFiltered(prev, Maps.<K>keyPredicateOnEntries(keyPredicate));
} else {
return new FilteredKeySetMultimap<>(unfiltered, keyPredicate);
}
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} whose keys satisfy a
* predicate. The returned multimap is a live view of {@code unfiltered}; changes to one affect
* the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a key that doesn't
* satisfy the predicate, the multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose keys satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code keyPredicate} must be <i>consistent with equals</i>, as documented at
* {@link Predicate#apply}. Do not provide a predicate such as {@code
* Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals.
*
* @since 14.0
*/
public static <K, V> ListMultimap<K, V> filterKeys(
ListMultimap<K, V> unfiltered, final Predicate<? super K> keyPredicate) {
if (unfiltered instanceof FilteredKeyListMultimap) {
FilteredKeyListMultimap<K, V> prev = (FilteredKeyListMultimap<K, V>) unfiltered;
return new FilteredKeyListMultimap<>(
prev.unfiltered(), Predicates.<K>and(prev.keyPredicate, keyPredicate));
} else {
return new FilteredKeyListMultimap<>(unfiltered, keyPredicate);
}
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} whose values satisfy a
* predicate. The returned multimap is a live view of {@code unfiltered}; changes to one affect
* the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a value that doesn't
* satisfy the predicate, the multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose value satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code valuePredicate} must be <i>consistent with equals</i>, as documented
* at {@link Predicate#apply}. Do not provide a predicate such as {@code
* Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals.
*
* @since 11.0
*/
public static <K, V> Multimap<K, V> filterValues(
Multimap<K, V> unfiltered, final Predicate<? super V> valuePredicate) {
return filterEntries(unfiltered, Maps.<V>valuePredicateOnEntries(valuePredicate));
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} whose values satisfy a
* predicate. The returned multimap is a live view of {@code unfiltered}; changes to one affect
* the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a value that doesn't
* satisfy the predicate, the multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose value satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code valuePredicate} must be <i>consistent with equals</i>, as documented
* at {@link Predicate#apply}. Do not provide a predicate such as {@code
* Predicates.instanceOf(ArrayList.class)}, which is inconsistent with equals.
*
* @since 14.0
*/
public static <K, V> SetMultimap<K, V> filterValues(
SetMultimap<K, V> unfiltered, final Predicate<? super V> valuePredicate) {
return filterEntries(unfiltered, Maps.<V>valuePredicateOnEntries(valuePredicate));
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} that satisfy a predicate. The
* returned multimap is a live view of {@code unfiltered}; changes to one affect the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a key/value pair that
* doesn't satisfy the predicate, multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose keys satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code entryPredicate} must be <i>consistent with equals</i>, as documented
* at {@link Predicate#apply}.
*
* @since 11.0
*/
public static <K, V> Multimap<K, V> filterEntries(
Multimap<K, V> unfiltered, Predicate<? super Entry<K, V>> entryPredicate) {
checkNotNull(entryPredicate);
if (unfiltered instanceof SetMultimap) {
return filterEntries((SetMultimap<K, V>) unfiltered, entryPredicate);
}
return (unfiltered instanceof FilteredMultimap)
? filterFiltered((FilteredMultimap<K, V>) unfiltered, entryPredicate)
: new FilteredEntryMultimap<K, V>(checkNotNull(unfiltered), entryPredicate);
}
/**
* Returns a multimap containing the mappings in {@code unfiltered} that satisfy a predicate. The
* returned multimap is a live view of {@code unfiltered}; changes to one affect the other.
*
* <p>The resulting multimap's views have iterators that don't support {@code remove()}, but all
* other methods are supported by the multimap and its views. When adding a key/value pair that
* doesn't satisfy the predicate, multimap's {@code put()}, {@code putAll()}, and {@code
* replaceValues()} methods throw an {@link IllegalArgumentException}.
*
* <p>When methods such as {@code removeAll()} and {@code clear()} are called on the filtered
* multimap or its views, only mappings whose keys satisfy the filter will be removed from the
* underlying multimap.
*
* <p>The returned multimap isn't threadsafe or serializable, even if {@code unfiltered} is.
*
* <p>Many of the filtered multimap's methods, such as {@code size()}, iterate across every
* key/value mapping in the underlying multimap and determine which satisfy the filter. When a
* live view is <i>not</i> needed, it may be faster to copy the filtered multimap and use the
* copy.
*
* <p><b>Warning:</b> {@code entryPredicate} must be <i>consistent with equals</i>, as documented
* at {@link Predicate#apply}.
*
* @since 14.0
*/
public static <K, V> SetMultimap<K, V> filterEntries(
SetMultimap<K, V> unfiltered, Predicate<? super Entry<K, V>> entryPredicate) {
checkNotNull(entryPredicate);
return (unfiltered instanceof FilteredSetMultimap)
? filterFiltered((FilteredSetMultimap<K, V>) unfiltered, entryPredicate)
: new FilteredEntrySetMultimap<K, V>(checkNotNull(unfiltered), entryPredicate);
}
/**
* Support removal operations when filtering a filtered multimap. Since a filtered multimap has
* iterators that don't support remove, passing one to the FilteredEntryMultimap constructor would
* lead to a multimap whose removal operations would fail. This method combines the predicates to
* avoid that problem.
*/
private static <K, V> Multimap<K, V> filterFiltered(
FilteredMultimap<K, V> multimap, Predicate<? super Entry<K, V>> entryPredicate) {
Predicate<Entry<K, V>> predicate =
Predicates.<Entry<K, V>>and(multimap.entryPredicate(), entryPredicate);
return new FilteredEntryMultimap<>(multimap.unfiltered(), predicate);
}
/**
* Support removal operations when filtering a filtered multimap. Since a filtered multimap has
* iterators that don't support remove, passing one to the FilteredEntryMultimap constructor would
* lead to a multimap whose removal operations would fail. This method combines the predicates to
* avoid that problem.
*/
private static <K, V> SetMultimap<K, V> filterFiltered(
FilteredSetMultimap<K, V> multimap, Predicate<? super Entry<K, V>> entryPredicate) {
Predicate<Entry<K, V>> predicate =
Predicates.<Entry<K, V>>and(multimap.entryPredicate(), entryPredicate);
return new FilteredEntrySetMultimap<>(multimap.unfiltered(), predicate);
}
static boolean equalsImpl(Multimap<?, ?> multimap, @Nullable Object object) {
if (object == multimap) {
return true;
}
if (object instanceof Multimap) {
Multimap<?, ?> that = (Multimap<?, ?>) object;
return multimap.asMap().equals(that.asMap());
}
return false;
}
// TODO(jlevy): Create methods that filter a SortedSetMultimap.
}