org.apache.axis2.jaxws.util
Class WeakKey

java.lang.Object
  java.lang.ref.Reference<T>
      java.lang.ref.WeakReference<Object>
          org.apache.axis2.jaxws.util.WeakKey

public class WeakKey
extends WeakReference<Object>

Implement a WeakReference key to be used in a collection. Being a WeakReference, it will not prevent the key from being Garbage Collected. The key can only be created with a reference queue so that users of this class provide cleanup logic which uses the items in the reference queue to cleanup entries in the collection. Note that the ReferenceQueue will contain the WeakKey instance that assocaited with the referent that was GC'd. So, the elements on the ReferenceQueue can be used to directly access and remove entries in the collection it is a key for. For example, one could do something like the following in cleanup logic: Object gcKey = null; while ((gcKey = q.poll()) != null) { WeakKey wk = (WeakKey) gcKey; removedEntry = collection.remove(wk); ... }

Constructor Summary

WeakKey(Object key, ReferenceQueue q)

Method Summary

static WeakKey	comparisonKey(Object checkKey) Return an instance of WeakKey that can be used in comparsion operations.
boolean	equals(Object o)
int	hashCode()

Methods inherited from class java.lang.ref.Reference

clear, enqueue, get, isEnqueued

Methods inherited from class java.lang.Object

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

Constructor Detail

WeakKey

public WeakKey(Object key,
               ReferenceQueue q)

Method Detail

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

comparisonKey

public static WeakKey comparisonKey(Object checkKey)

Return an instance of WeakKey that can be used in comparsion operations. For example, it can be used to lookup a key in a collection that has a WeakKey as the key.

Parameters:

checkKey - the key value

Returns:

an instance of WeakKey for the value