Class CopyOnWriteHashMap<K,​V>

  • All Implemented Interfaces:

    public final class CopyOnWriteHashMap<K,​V>
    extends java.util.AbstractMap<K,​V>
    An immutable map whose writes result in a new copy of the map to be created. This is essentially a hash array mapped trie: inner nodes use a bitmap in order to map hashes to slots by counting ones. In case of a collision (two values having the same 32-bits hash), a leaf node is created which stores and searches for values sequentially. Reads and writes both perform in logarithmic time. Null keys and values are not supported. This structure might need to perform several object creations per write so it is better suited for work-loads that are not too write-intensive.
    See Also:
    the wikipedia page
    • Nested Class Summary

      • Nested classes/interfaces inherited from class java.util.AbstractMap

        java.util.AbstractMap.SimpleEntry<K extends java.lang.Object,​V extends java.lang.Object>, java.util.AbstractMap.SimpleImmutableEntry<K extends java.lang.Object,​V extends java.lang.Object>
      • Nested classes/interfaces inherited from interface java.util.Map

        java.util.Map.Entry<K extends java.lang.Object,​V extends java.lang.Object>
    • Constructor Summary

      Constructor Description
      Create a new empty map.
    • Constructor Detail

      • CopyOnWriteHashMap

        public CopyOnWriteHashMap()
        Create a new empty map.
    • Method Detail

      • copyOf

        public static <K,​V> CopyOnWriteHashMap<K,​V> copyOf​(java.util.Map<? extends K,​? extends V> map)
        Return a copy of the provided map.
      • appendElement

        public static <T> T[] appendElement​(T[] array,
                                            T element)
      • insertElement

        public static <T> T[] insertElement​(T[] array,
                                            T element,
                                            int index)
      • containsKey

        public boolean containsKey​(java.lang.Object key)
        Specified by:
        containsKey in interface java.util.Map<K,​V>
        containsKey in class java.util.AbstractMap<K,​V>
      • get

        public V get​(java.lang.Object key)
        Specified by:
        get in interface java.util.Map<K,​V>
        get in class java.util.AbstractMap<K,​V>
      • size

        public int size()
        Specified by:
        size in interface java.util.Map<K,​V>
        size in class java.util.AbstractMap<K,​V>
      • copyAndPut

        public CopyOnWriteHashMap<K,​V> copyAndPut​(K key,
                                                        V value)
        Associate key with value and return a new copy of the hash table. The current hash table is not modified.
      • copyAndPutAll

        public <K1 extends K,​V1 extends VCopyOnWriteHashMap<K,​V> copyAndPutAll​(java.lang.Iterable<java.util.Map.Entry<K1,​V1>> entries)
      • copyAndPutAll

        public <K1 extends K,​V1 extends VCopyOnWriteHashMap<K,​V> copyAndPutAll​(<java.util.Map.Entry<K1,​V1>> entries)
      • copyAndRemove

        public CopyOnWriteHashMap<K,​V> copyAndRemove​(java.lang.Object key)
        Remove the given key from this map. The current hash table is not modified.
      • entrySet

        public java.util.Set<java.util.Map.Entry<K,​V>> entrySet()
        Specified by:
        entrySet in interface java.util.Map<K,​V>
        Specified by:
        entrySet in class java.util.AbstractMap<K,​V>