/*
 * 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 com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import org.checkerframework.checker.nullness.qual.Nullable;

Basic implementation of the ListMultimap interface. It's a wrapper around AbstractMapBasedMultimap that converts the returned collections into Lists. The createCollection method must return a List. 
Author:
Jared Levy
Since:
2.0/**
 * Basic implementation of the {@link ListMultimap} interface. It's a wrapper around {@link
 * AbstractMapBasedMultimap} that converts the returned collections into {@code Lists}. The {@link
 * #createCollection} method must return a {@code List}.
 *
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
abstract class AbstractListMultimap<K, V> extends AbstractMapBasedMultimap<K, V>
    implements ListMultimap<K, V> {
  
Creates a new multimap that uses the provided map.
Params:
map – place to store the mapping from each key to its corresponding values/**
   * Creates a new multimap that uses the provided map.
   *
   * @param map place to store the mapping from each key to its corresponding values
   */
  protected AbstractListMultimap(Map<K, Collection<V>> map) {
    super(map);
  }

  @Override
  abstract List<V> createCollection();

  @Override
  List<V> createUnmodifiableEmptyCollection() {
    return Collections.emptyList();
  }

  @Override
  <E> Collection<E> unmodifiableCollectionSubclass(Collection<E> collection) {
    return Collections.unmodifiableList((List<E>) collection);
  }

  @Override
  Collection<V> wrapCollection(K key, Collection<V> collection) {
    return wrapList(key, (List<V>) collection, null);
  }

  // Following Javadoc copied from ListMultimap.

  
{@inheritDoc}
Because the values for a given key may have duplicates and follow the insertion ordering, this method returns a List, instead of the Collection specified in the Multimap interface. /**
   * {@inheritDoc}
   *
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,
   * this method returns a {@link List}, instead of the {@link Collection} specified in the {@link
   * Multimap} interface.
   */
  @Override
  public List<V> get(@Nullable K key) {
    return (List<V>) super.get(key);
  }

  
{@inheritDoc}
Because the values for a given key may have duplicates and follow the insertion ordering, this method returns a List, instead of the Collection specified in the Multimap interface. /**
   * {@inheritDoc}
   *
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,
   * this method returns a {@link List}, instead of the {@link Collection} specified in the {@link
   * Multimap} interface.
   */
  @CanIgnoreReturnValue
  @Override
  public List<V> removeAll(@Nullable Object key) {
    return (List<V>) super.removeAll(key);
  }

  
{@inheritDoc}
Because the values for a given key may have duplicates and follow the insertion ordering, this method returns a List, instead of the Collection specified in the Multimap interface. /**
   * {@inheritDoc}
   *
   * <p>Because the values for a given key may have duplicates and follow the insertion ordering,
   * this method returns a {@link List}, instead of the {@link Collection} specified in the {@link
   * Multimap} interface.
   */
  @CanIgnoreReturnValue
  @Override
  public List<V> replaceValues(@Nullable K key, Iterable<? extends V> values) {
    return (List<V>) super.replaceValues(key, values);
  }

  
Stores a key-value pair in the multimap.
Params:
key – key to store in the multimap
value – value to store in the multimap
Returns:
true always/**
   * Stores a key-value pair in the multimap.
   *
   * @param key key to store in the multimap
   * @param value value to store in the multimap
   * @return {@code true} always
   */
  @CanIgnoreReturnValue
  @Override
  public boolean put(@Nullable K key, @Nullable V value) {
    return super.put(key, value);
  }

  
{@inheritDoc}
Though the method signature doesn't say so explicitly, the returned map has List values. /**
   * {@inheritDoc}
   *
   * <p>Though the method signature doesn't say so explicitly, the returned map has {@link List}
   * values.
   */
  @Override
  public Map<K, Collection<V>> asMap() {
    return super.asMap();
  }

  
Compares the specified object to this multimap for equality.
Two ListMultimap instances are equal if, for each key, they contain the same values in the same order. If the value orderings disagree, the multimaps will not be considered equal. /**
   * Compares the specified object to this multimap for equality.
   *
   * <p>Two {@code ListMultimap} instances are equal if, for each key, they contain the same values
   * in the same order. If the value orderings disagree, the multimaps will not be considered equal.
   */
  @Override
  public boolean equals(@Nullable Object object) {
    return super.equals(object);
  }

  private static final long serialVersionUID = 6588350623831699109L;
}