java.lang.ref

Class WeakReference

java.lang.Object

java.lang.ref.Reference

java.lang.ref.WeakReference

public class WeakReference
extends Reference

This class provides support for weak references. Weak references are most often used to implement canonicalizing mappings. Suppose that the garbage collector determines at a certain point in time that an object is weakly reachable. At that time it will atomically clear all the weak references to that object and all weak references to any other weakly- reachable objects from which that object is reachable through a chain of strong and weak references.

Since:

JDK1.2, CLDC 1.1

Constructor Summary

Constructors

Constructor and Description
WeakReference(Object referent) Creates a new weak reference that refers to the given object.

Method Summary

Methods

Modifier and Type	Method and Description
void	clear() Clears this reference object.
Object	get() Returns this reference object's referent.

Methods inherited from class java.lang.Object

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

Constructor Detail

WeakReference

public WeakReference(Object referent)

Creates a new weak reference that refers to the given object.

Method Detail

get

public Object get()

Returns this reference object's referent. If this reference object has been cleared, either by the program or by the garbage collector, then this method returns null.

Overrides:

get in class Reference

Returns:

The object to which this reference refers, or null if this reference object has been cleared

clear

public void clear()

Clears this reference object.

Overrides:

clear in class Reference