Class ReferenceQueue<T>
java.lang.Object
java.lang.ref.ReferenceQueue<T>
- Type Parameters:
T
- the type of the reference object
Reference queues, to which registered reference objects are appended by the
garbage collector after the appropriate reachability changes are detected.
- Since:
- 1.2
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Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionpoll()
Polls this queue to see if a reference object is available.remove()
Removes the next reference object in this queue, blocking until one becomes available.remove
(long timeout) Removes the next reference object in this queue, blocking until either one becomes available or the given timeout period expires.
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Constructor Details
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ReferenceQueue
public ReferenceQueue()Constructs a new reference-object queue.
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Method Details
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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 returnsnull
.- Returns:
- A reference object, if one was immediately available,
otherwise
null
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remove
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 totimeout
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 negativeInterruptedException
- If the timeout wait is interrupted
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remove
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
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