Package org.apache.commons.collections4.multimap

Class ArrayListValuedHashMap<K,​V>

  • Type Parameters:
    K - the type of the keys in this map
    V - the type of the values in this map
    All Implemented Interfaces:
    Serializable, ListValuedMap<K,​V>, MultiValuedMap<K,​V>
    public class ArrayListValuedHashMap<K,​V>
extends AbstractListValuedMap<K,​V>
implements Serializable
    Implements a ListValuedMap, using a HashMap to provide data storage and ArrayLists as value collections. This is the standard implementation of a ListValuedMap.

    Note that ArrayListValuedHashMap is not synchronized and is not thread-safe. If you wish to use this map from multiple threads concurrently, you must use appropriate synchronization. This class may throw exceptions when accessed by concurrent threads without synchronization.

    Since:
    4.1
    See Also:
    Serialized Form

    • Constructor Detail

      • ArrayListValuedHashMap

        public ArrayListValuedHashMap()
        Creates an empty ArrayListValuedHashMap with the default initial map capacity (16) and the default initial list capacity (3).

      • ArrayListValuedHashMap

        public ArrayListValuedHashMap​(int initialListCapacity)
        Creates an empty ArrayListValuedHashMap with the default initial map capacity (16) and the specified initial list capacity.
        Parameters:
        initialListCapacity - the initial capacity used for value collections

      • ArrayListValuedHashMap

        public ArrayListValuedHashMap​(int initialMapCapacity,
                              int initialListCapacity)
        Creates an empty ArrayListValuedHashMap with the specified initial map and list capacities.
        Parameters:
        initialMapCapacity - the initial hashmap capacity
        initialListCapacity - the initial capacity used for value collections

      • ArrayListValuedHashMap

        public ArrayListValuedHashMap​(MultiValuedMap<? extends K,​? extends V> map)
        Creates an ArrayListValuedHashMap copying all the mappings of the given map.
        Parameters:
        map - a MultiValuedMap to copy into this map

      • ArrayListValuedHashMap

        public ArrayListValuedHashMap​(Map<? extends K,​? extends V> map)
        Creates an ArrayListValuedHashMap copying all the mappings of the given map.
        Parameters:
        map - a Map to copy into this map

    • Method Detail

      • trimToSize

        public void trimToSize()
        Trims the capacity of all value collections to their current size.