Package com.yahoo.yolean.concurrent

Class CopyOnWriteHashMap<K,​V>

  • All Implemented Interfaces:
    java.util.Map<K,​V>
    public class CopyOnWriteHashMap<K,​V>
extends java.lang.Object
implements java.util.Map<K,​V>

    This is a thread hash map for small collections that are stable once built. Until it is stable there will be a race among all threads missing something in the map. They will then clone the map add the missing stuff and then put it back as active again. Here are no locks, but the cost is that inserts will happen a lot more than necessary. The map reference is volatile, but on most multi-cpu machines that has no cost unless modified.

    Author:
    baldersheim

    • Nested Class Summary

      • Nested classes/interfaces inherited from interface java.util.Map

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

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void clear()  
      boolean containsKey​(java.lang.Object key)  
      boolean containsValue​(java.lang.Object value)  
      java.util.Set<java.util.Map.Entry<K,​V>> entrySet()  
      V get​(java.lang.Object key)  
      boolean isEmpty()  
      java.util.Set<K> keySet()  
      V put​(K key, V value)  
      void putAll​(java.util.Map<? extends K,​? extends V> m)  
      V remove​(java.lang.Object key)  
      int size()  
      java.util.Collection<V> values()  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

      • Methods inherited from interface java.util.Map

        compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

    • Constructor Detail

      • CopyOnWriteHashMap

        public CopyOnWriteHashMap()

    • Method Detail

      • size

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

      • isEmpty

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

      • containsKey

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

      • containsValue

        public boolean containsValue​(java.lang.Object value)
        Specified by:
        containsValue in interface java.util.Map<K,​V>

      • get

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

      • put

        public V put​(K key,
             V value)
        Specified by:
        put in interface java.util.Map<K,​V>

      • remove

        public V remove​(java.lang.Object key)
        Specified by:
        remove in interface java.util.Map<K,​V>

      • putAll

        public void putAll​(java.util.Map<? extends K,​? extends V> m)
        Specified by:
        putAll in interface java.util.Map<K,​V>

      • clear

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

      • keySet

        public java.util.Set<K> keySet()
        Specified by:
        keySet in interface java.util.Map<K,​V>

      • values

        public java.util.Collection<V> values()
        Specified by:
        values in interface java.util.Map<K,​V>

      • entrySet

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