added in API level 1

ReferenceQueue

public class ReferenceQueue
extends Object

java.lang.Object
   ↳ java.lang.ref.ReferenceQueue<T>


Reference queues, to which registered reference objects are appended by the garbage collector after the appropriate reachability changes are detected.

Summary

Public constructors

ReferenceQueue()

Constructs a new reference-object queue.

Public methods

Reference<? extends T> poll()

Polls this queue to see if a reference object is available.

Reference<? extends T> remove(long timeout)

Removes the next reference object in this queue, blocking until either one becomes available or the given timeout period expires.

Reference<? extends T> remove()

Removes the next reference object in this queue, blocking until one becomes available.

Inherited methods

Public constructors

ReferenceQueue

added in API level 1
public ReferenceQueue ()

Constructs a new reference-object queue.

Public methods

poll

added in API level 1
public Reference<? extends T> poll ()

Polls this queue to see if a reference object is available. If one is available without further delay then it is removed from the queue and returned. Otherwise this method immediately returns null.

Returns
Reference<? extends T> A reference object, if one was immediately available, otherwise null

remove

added in API level 1
public Reference<? extends T> remove (long timeout)

Removes the next reference object in this queue, blocking until either one becomes available or the given timeout period expires.

This method does not offer real-time guarantees: It schedules the timeout as if by invoking the Object.wait(long) method.

Parameters
timeout long: If positive, block for up to timeout milliseconds while waiting for a reference to be added to this queue. If zero, block indefinitely.

Returns
Reference<? extends T> A reference object, if one was available within the specified timeout period, otherwise null

Throws
IllegalArgumentException If the value of the timeout argument is negative
InterruptedException If the timeout wait is interrupted

remove

added in API level 1
public Reference<? extends T> remove ()

Removes the next reference object in this queue, blocking until one becomes available.

Returns
Reference<? extends T> A reference object, blocking until one becomes available

Throws
InterruptedException If the wait is interrupted