java.lang.ref
Class ReferenceQueuejava.lang.Object | +--java.lang.ref.ReferenceQueue
- public class ReferenceQueue
- extends Object
Reference queues, to which registered reference objects are appended by the garbage collector after the appropriate reachability changes are detected.
- Since:
- 1.2
Constructor Summary
ReferenceQueue()
Constructs a new reference-object queue.
Method Summary
Reference poll()
Polls this queue to see if a reference object is available.Reference remove()
Removes the next reference object in this queue, blocking until one becomes available.Reference remove(long timeout)
Removes the next reference object in this queue, blocking until either one becomes available or the given timeout period expires.
Methods inherited from class java.lang.Object clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
ReferenceQueue
public ReferenceQueue()
- Constructs a new reference-object queue.
Method Detail
poll
public Reference 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:
- A reference object, if one was immediately available, otherwise null
remove
public Reference remove(long timeout) throws IllegalArgumentException, InterruptedException
- 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 - If positive, block for up timeout milliseconds while waiting for a reference to be added to this queue. If zero, block indefinitely.
- Returns:
- 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
public Reference remove() throws InterruptedException
- Removes the next reference object in this queue, blocking until one becomes available.
- Returns:
- A reference object, blocking until one becomes available
- Throws:
- InterruptedException - If the wait is interrupted