Module org.glassfish.hk2.utilities
Package org.glassfish.hk2.utilities.general.internal

Class WeakHashClockImpl<K,V>

java.lang.Object
org.glassfish.hk2.utilities.general.internal.WeakHashClockImpl<K,V>
All Implemented Interfaces:
WeakHashClock<K,V>
public class WeakHashClockImpl<K,V> extends Object implements WeakHashClock<K,V>
Implementation of WeakHashClock as needed by the CAR algorithm
Author:
jwells

  • Constructor Summary

    Constructors
    Constructor
    Description
    WeakHashClockImpl(boolean isWeak)
     

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    clear()
    Sets the clock size back to zero, no entries
    void
    clearStaleReferences()
    Causes stale references to be cleared from the data structures.
    V
    get(K key)
    Gets the given key, returning null if not found
    boolean
    hasWeakKeys()
    Tells if this WeakHashClock has Weak keys
    Map.Entry<K,V>
    next()
    Returns the next key/value pair in the clock, or null if the clock has no members.
    void
    put(K key, V value)
    Adds the given pair to the clock.
    void
    releaseMatching(CacheKeyFilter<K> filter)
    Releases all key/value pairs that match the filter
    V
    remove(K key)
    Removes the given key from the clock, if found
    int
    size()
    Returns the number of elements currently in the clock.
    String
    toString()
     

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • WeakHashClockImpl

      public WeakHashClockImpl(boolean isWeak)

  • Method Details

    • put

      public void put(K key, V value)
      Description copied from interface: WeakHashClock
      Adds the given pair to the clock. It will be placed at the current tail of the clock
      Specified by:
      put in interface WeakHashClock<K,V>
      Parameters:
      key - Must not be null
      value - May not be null

    • get

      public V get(K key)
      Description copied from interface: WeakHashClock
      Gets the given key, returning null if not found
      Specified by:
      get in interface WeakHashClock<K,V>
      Parameters:
      key - The key to search for, may not be null
      Returns:
      The value found, or null if not found

    • remove

      public V remove(K key)
      Description copied from interface: WeakHashClock
      Removes the given key from the clock, if found
      Specified by:
      remove in interface WeakHashClock<K,V>
      Parameters:
      key - The key to remove, may not be null
      Returns:
      The value removed if found, or null if not found

    • releaseMatching

      public void releaseMatching(CacheKeyFilter<K> filter)
      Description copied from interface: WeakHashClock
      Releases all key/value pairs that match the filter
      Specified by:
      releaseMatching in interface WeakHashClock<K,V>
      Parameters:
      filter - A non-null filter that can be used to delete every key/value pair that matches the filter

    • size

      public int size()
      Description copied from interface: WeakHashClock
      Returns the number of elements currently in the clock. References that have gone away because they were weakly referenced will not be counted in the size
      Specified by:
      size in interface WeakHashClock<K,V>
      Returns:
      The number of entries currently in the clock

    • next

      public Map.Entry<K,V> next()
      Description copied from interface: WeakHashClock
      Returns the next key/value pair in the clock, or null if the clock has no members. This will advance the head and tail of the clock to the next element. If the WeakReference for the returned element is null then this element will also have been removed from the clock by this operation
      Specified by:
      next in interface WeakHashClock<K,V>
      Returns:
      The next key/value pair in the

    • clear

      public void clear()
      Description copied from interface: WeakHashClock
      Sets the clock size back to zero, no entries
      Specified by:
      clear in interface WeakHashClock<K,V>

    • clearStaleReferences

      public void clearStaleReferences()
      Description copied from interface: WeakHashClock
      Causes stale references to be cleared from the data structures. Since this is a weak clock the references can go away at any time, which happens whenever any operation has been performed. However, it may be the case that no operation will be performed for a while and so this method is provided to have a no-op operation to call in order to clear out any stale references
      Specified by:
      clearStaleReferences in interface WeakHashClock<K,V>

    • hasWeakKeys

      public boolean hasWeakKeys()
      Description copied from interface: WeakHashClock
      Tells if this WeakHashClock has Weak keys
      Specified by:
      hasWeakKeys in interface WeakHashClock<K,V>
      Returns:
      true if this map has weak keys, true otherwise

    • toString

      public String toString()
      Overrides:
      toString in class Object