Package com.tangosol.util

Class CopyOnWriteMap<K,​V>

  • All Implemented Interfaces:
    Map<K,​V>
    public class CopyOnWriteMap<K,​V>
extends Object
implements Map<K,​V>
    A thread-safe variant of Map in which all mutating operations (e.g. put, putAll) are implemented by making a fresh copy of the underlying map.

    Iterators over this map are guaranteed to produce a safe-iteration and not to throw ConcurrentModificationException. The iterator will not reflect concurrent additions, removals, or changes to this map.

    Note: mutations on this map are costly, but may be more efficient than alternatives when "get" operations vastly outnumber mutations. All mutating operations are synchronized, so concurrent mutation can be prevented by holding synchronization on this object.

    Since:
    Coherence 3.7.2
    Author:
    pp 2011.09.17, rhl 2010.09.09 (from CopyOnWriteLongArray)

    • Constructor Detail

      • CopyOnWriteMap

        public CopyOnWriteMap​(Class clazz)

      • CopyOnWriteMap

        public CopyOnWriteMap​(Map<K,​V> map)
        Construct a CopyOnWriteMap, initialized with the contents of the specified map.
        Parameters:
        map - the initial map

    • Method Detail

      • getInternalMap

        protected Map<K,​V> getInternalMap()
        Return the internal map.
        Returns:
        the internal map

      • setInternalMap

        protected void setInternalMap​(Map<K,​V> map)
        Set the internal map.
        Parameters:
        map - the new internal map

      • instantiateMap

        protected Map<K,​V> instantiateMap​(Class clazz)
        Create a new instance of Map based on the provided Class.
        Parameters:
        clazz - the type of Map to instantiate
        Returns:
        a new empty instance of Map
        Throws:
        IllegalArgumentException - if the provided Class does not implement Map.

      • copyMap

        protected Map<K,​V> copyMap​(Map<K,​V> map)
        Create an instance of Map based on the contents of the provided map.
        Parameters:
        map - the map to copy
        Returns:
        an instance of Map populated with the contents of the provided map

      • size

        public int size()
        Specified by:
        size in interface Map<K,​V>

      • isEmpty

        public boolean isEmpty()
        Specified by:
        isEmpty in interface Map<K,​V>

      • containsKey

        public boolean containsKey​(Object oKey)
        Specified by:
        containsKey in interface Map<K,​V>

      • containsValue

        public boolean containsValue​(Object oValue)
        Specified by:
        containsValue in interface Map<K,​V>

      • get

        public V get​(Object oKey)
        Specified by:
        get in interface Map<K,​V>

      • put

        public V put​(K oKey,
             V oValue)
        Specified by:
        put in interface Map<K,​V>

      • remove

        public V remove​(Object oKey)
        Specified by:
        remove in interface Map<K,​V>

      • putAll

        public void putAll​(Map<? extends K,​? extends V> map)
        Specified by:
        putAll in interface Map<K,​V>

      • clear

        public void clear()
        Specified by:
        clear in interface Map<K,​V>

      • keySet

        public Set<K> keySet()
        Returns a Set view of the keys contained in the underlying map.
        Specified by:
        keySet in interface Map<K,​V>
        Returns:
        a Set view of the keys contained in the underlying map

      • entrySet

        public Set<Map.Entry<K,​V>> entrySet()
        Return a set view of the underlying map.
        Specified by:
        entrySet in interface Map<K,​V>
        Returns:
        a set view of the underlying map