org.springframework.util

## 接口 MultiValueMap<K,V>

- 类型参数:
    `K` - the key type
    `V` - the value element type
  所有超级接口:
    Map<K,List<V>>
  所有已知实现类:
    LinkedMultiValueMap

      public interface MultiValueMap<K,V>
      extends Map<K,List<V>>

  Extension of the `Map` interface that stores multiple values.
  从以下版本开始:
    3.0
  作者:
    Arjen Poutsma

- - ### 嵌套类概要

    - ### 从接口继承的嵌套类/接口 java.util.Map

      `Map.Entry<K,V>`

  - ### 方法概要

    所有方法 实例方法 抽象方法
    限定符和类型 | 方法和说明
    --- | ---
    `void` | `add(K key, V value)` Add the given single value to the current list of values for the given key.
    `void` | `addAll(K key, List<? extends V> values)` Add all the values of the given list to the current list of values for the given key.
    `void` | `addAll(MultiValueMap<K,V> values)` Add all the values of the given `MultiValueMap` to the current values.
    `V` | `getFirst(K key)` Return the first value for the given key.
    `void` | `set(K key, V value)` Set the given single value under the given key.
    `void` | `setAll(Map<K,V> values)` Set the given values under.
    `Map<K,V>` | `toSingleValueMap()` Return a `Map` with the first values contained in this `MultiValueMap`.

    - ### 从接口继承的方法 java.util.Map

      `clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values`

- - ### 方法详细资料

    - #### getFirst

          @Nullable
          V getFirst(K key)

      Return the first value for the given key.
      参数:
        `key` - the key
      返回:
        the first value for the specified key, or `null` if none

    - #### add

          void add(K key,
                   @Nullable
                   V value)

      Add the given single value to the current list of values for the given key.
      参数:
        `key` - the key
        `value` - the value to be added

    - #### addAll

          void addAll(K key,
                      List<? extends V> values)

      Add all the values of the given list to the current list of values for the given key.
      参数:
        `key` - they key
        `values` - the values to be added
      从以下版本开始:
        5.0

    - #### addAll

          void addAll(MultiValueMap<K,V> values)

      Add all the values of the given `MultiValueMap` to the current values.
      参数:
        `values` - the values to be added
      从以下版本开始:
        5.0

    - #### set

          void set(K key,
                   @Nullable
                   V value)

      Set the given single value under the given key.
      参数:
        `key` - the key
        `value` - the value to set

    - #### setAll

          void setAll(Map<K,V> values)

      Set the given values under.
      参数:
        `values` - the values.

    - #### toSingleValueMap

          Map<K,V> toSingleValueMap()

      Return a `Map` with the first values contained in this `MultiValueMap`.
      返回:
        a single value representation of this map