java.lang.ref.WeakReference Maven / Gradle / Ivy
/*
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This work corresponds to the API signatures of JSR 219: Foundation
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*/
package java.lang.ref;
/**
* Weak reference objects, which do not prevent their referents from being
* made finalizable, finalized, and then reclaimed. 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 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 soft
* references. At the same time it will declare all of the formerly
* weakly-reachable objects to be finalizable. At the same time or at some
* later time it will enqueue those newly-cleared weak references that are
* registered with reference queues.
*
* @version 1.11, 02/02/00
* @author Mark Reinhold
* @since 1.2
*/
public class WeakReference extends Reference
{
/**
* Creates a new weak reference that refers to the given object. The new
* reference is not registered with any queue.
*
* @param referent object the new weak reference will refer to
*/
public WeakReference(Object referent) {
super(referent);
}
/**
* Creates a new weak reference that refers to the given object and is
* registered with the given queue.
*
* @param referent object the new weak reference will refer to
* @param q queue the weak reference is registered with
* @throws NullPointerException If the queue argument
* is null
*
*/
public WeakReference(Object referent, ReferenceQueue q) {
super(referent, q);
}
}