guava中Multimap、HashMultimap用法小结

@GwtCompatible
public interface Multimap<K, V> {
  //返回Multimap集合的key、value pair的数量  
  int size();
  //判断Multimap是否包含key、value pair
  boolean isEmpty();
  //判断Multimap中是否包含指定key的value值
  boolean containsKey(@Nullable Object key);
  //判断Multimap中是否包含指定value的key
  boolean containsValue(@Nullable Object value);
  //判断Multimap中是否包含指定的key-value pair的数据
  boolean containsEntry(@Nullable Object key, @Nullable Object value);
  //将数据加入到Multimap中
  boolean put(@Nullable K key, @Nullable V value);
  //删除Multimap中指定key-value pair
  boolean remove(@Nullable Object key, @Nullable Object value);
  //将指定的key-集合数据加入Multimap中
  boolean putAll(@Nullable K key, Iterable<? extends V> values);
  //将指定的Multimap和当前的Multimap合并
  boolean putAll(Multimap<? extends K, ? extends V> multimap);
  //替换指定key的value
  Collection<V> replaceValues(@Nullable K key, Iterable<? extends V> values);
  //删除Imultimap中的指定key数据
  Collection<V> removeAll(@Nullable Object key);
  //清空Imultimap中的数据
  void clear();
  //获取指定key的值
  Collection<V> get(@Nullable K key);
  //获取所有的key集合
  Set<K> keySet();

  Multiset<K> keys();

  Collection<V> values();

  Collection<Map.Entry<K, V>> entries();

  Map<K, Collection<V>> asMap();

  @Override
  boolean equals(@Nullable Object obj);

  @Override
  int hashCode();
}

Multimap<Integer, Integer> map = HashMultimap.<Integer, Integer>create();
        map.put(1, 2);
        map.put(1, 2);
        map.put(1, 3);
        map.put(1, 4);
        map.put(2, 3);
        map.put(3, 3);
        map.put(4, 3);
        map.put(5, 3);
        System.out.println(map);

{1=[4, 2, 3], 2=[3], 3=[3], 4=[3], 5=[3]}

 //判断集合中是否存在key-value为指定值得元素
        System.out.println(map.containsEntry(1, 2));
        System.out.println(map.containsEntry(1, 6));
        //获取key为1的value集合
        Collection<Integer> list = map.get(1);
        System.out.println(list);
        //返回集合中所有key的集合，重复的key将会用key * num的方式来表示
        Multiset<Integer> set = map.keys();
        System.out.println(set);
        //返回集合中所有不重复的key的集合
        Set<Integer> kset = map.keySet();
        System.out.println(kset);

true
false
[4, 2, 3]
[1 x 3, 2 x 2, 3, 4, 5]
[1, 2, 3, 4, 5]

Collection<Integer> coll = map.replaceValues(1, Arrays.asList(1,7,8,9,10));
        System.out.println(coll);
        System.out.println(map);

[4, 2, 3]
{1=[8, 9, 1, 10, 7], 2=[4, 3], 3=[3], 4=[3], 5=[3]}

 //创建一个静态不可变的Multimap对象
        Multimap<Integer, Integer> map = ImmutableMultimap.<Integer, Integer>of();
        Multimap<Integer, Integer> map1 = ImmutableMultimap.<Integer, Integer>builder().build();
        //从另外一个集合中复制数据元素到Multimap对象中
        Multimap<Integer, Integer> map2 = ImmutableMultimap.copyOf(map);

 Multimap<Integer, Integer> map = LinkedHashMultimap.<Integer, Integer>create();
        map.putAll(4, Arrays.asList(5,3,4,2,1,56));
        map.putAll(3, Arrays.asList(3,4,2,6,8,7));
        map.put(1, 2);
        System.out.println(map);

 Multimap<Integer, Integer> map = TreeMultimap.<Integer, Integer>create();
        map.putAll(4, Arrays.asList(5,3,4,2,1,56));
        map.putAll(3, Arrays.asList(3,4,2,6,8,7));
        map.put(1, 2);
        System.out.println(map);