org.hypergraphdb.handle
Class PhantomHandle

java.lang.Object
  java.lang.ref.Reference<T>
      java.lang.ref.PhantomReference<java.lang.Object>
          org.hypergraphdb.handle.PhantomHandle

All Implemented Interfaces:

java.lang.Comparable<HGHandle>, HGLiveHandle, HGHandle

Direct Known Subclasses:

PhantomManagedHandle

public class PhantomHandle
extends java.lang.ref.PhantomReference<java.lang.Object>
implements HGLiveHandle, java.lang.Comparable<HGHandle>

An implementation of a live handle that tracks garbage collection activity by extending PhantomReference.

Author:

Borislav Iordanov

Field Summary

static java.lang.ThreadLocal<java.lang.Boolean>

returnEnqueued This is for internal use ONLY.

Constructor Summary

PhantomHandle(java.lang.Object ref, HGPersistentHandle persistentHandle, byte flags, java.lang.ref.ReferenceQueue<java.lang.Object> refQueue)

Method Summary

void	accessed()
int	compareTo(HGHandle h)
boolean	equals(java.lang.Object other)
java.lang.Object	fetchRef() A getter of the referent that uses reflection to access the field directly.
byte	getFlags()
HGPersistentHandle	getPersistentHandle()
java.lang.Object	getRef()
int	hashCode()
void	storeRef(java.lang.Object ref) A setter of the referent.
java.lang.String	toString()

Methods inherited from class java.lang.ref.PhantomReference

get

Methods inherited from class java.lang.ref.Reference

clear, enqueue, isEnqueued

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

returnEnqueued

public static java.lang.ThreadLocal<java.lang.Boolean> returnEnqueued

This is for internal use ONLY.

See comments in 'getRef' for information about this variable.

Constructor Detail

PhantomHandle

public PhantomHandle(java.lang.Object ref,
                     HGPersistentHandle persistentHandle,
                     byte flags,
                     java.lang.ref.ReferenceQueue<java.lang.Object> refQueue)

Method Detail

getFlags

public byte getFlags()

Specified by:

getFlags in interface HGLiveHandle

getPersistentHandle

public HGPersistentHandle getPersistentHandle()

Specified by:

getPersistentHandle in interface HGLiveHandle

fetchRef

public java.lang.Object fetchRef()

A getter of the referent that uses reflection to access the field directly. Thus, the field is available even after it's finalized. Therefore, this method should only be called if it doesn't result in the referent becoming strongly reachable again.

storeRef

public void storeRef(java.lang.Object ref)

A setter of the referent. This setter will block the current Thread while the reference is being enqueued by the grabage collector.

Parameters:

ref -

getRef

public java.lang.Object getRef()

Specified by:

getRef in interface HGLiveHandle

accessed

public void accessed()

hashCode

public final int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public final boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

compareTo

public int compareTo(HGHandle h)

Specified by:

compareTo in interface java.lang.Comparable<HGHandle>