001/*
002 * Copyright (C) 2010 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package com.google.common.collect;
018
019import com.google.common.annotations.GwtCompatible;
020import com.google.errorprone.annotations.CanIgnoreReturnValue;
021import java.util.Map.Entry;
022import java.util.Set;
023import javax.annotation.CheckForNull;
024import org.checkerframework.checker.nullness.qual.Nullable;
025
026/**
027 * A set multimap which forwards all its method calls to another set multimap. Subclasses should
028 * override one or more methods to modify the behavior of the backing multimap as desired per the <a
029 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
030 *
031 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
032 * default} methods. Instead, it inherits their default implementations. When those implementations
033 * invoke methods, they invoke methods on the {@code ForwardingSetMultimap}.
034 *
035 * @author Kurt Alfred Kluever
036 * @since 3.0
037 */
038@GwtCompatible
039@ElementTypesAreNonnullByDefault
040public abstract class ForwardingSetMultimap<K extends @Nullable Object, V extends @Nullable Object>
041    extends ForwardingMultimap<K, V> implements SetMultimap<K, V> {
042
043  @Override
044  protected abstract SetMultimap<K, V> delegate();
045
046  @Override
047  public Set<Entry<K, V>> entries() {
048    return delegate().entries();
049  }
050
051  @Override
052  public Set<V> get(@ParametricNullness K key) {
053    return delegate().get(key);
054  }
055
056  @CanIgnoreReturnValue
057  @Override
058  public Set<V> removeAll(@CheckForNull Object key) {
059    return delegate().removeAll(key);
060  }
061
062  @CanIgnoreReturnValue
063  @Override
064  public Set<V> replaceValues(@ParametricNullness K key, Iterable<? extends V> values) {
065    return delegate().replaceValues(key, values);
066  }
067}