Module java.base
Package java.lang.ref

Class ReferenceQueue<T>

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

public class ReferenceQueue<T> extends Object
ReferenceQueue is the container on which reference objects are enqueued when their reachability type is detected for the referent.
Since:
1.2
  • Constructor Summary

    Constructors
    Constructor
    Description
    Constructs a new instance of this class.
  • Method Summary

    Modifier and Type
    Method
    Description
    Reference<? extends T>
    Returns the next available reference from the queue if one is enqueued, null otherwise.
    Reference<? extends T>
    Return the next available enqueued reference on the queue, blocking indefinitely until one is available.
    Reference<? extends T>
    remove(long timeout)
    Return the next available enqueued reference on the queue, blocking up to the time given until one is available.

    Methods declared in class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • ReferenceQueue

      public ReferenceQueue()
      Constructs a new instance of this class.
  • Method Details

    • poll

      public Reference<? extends T> poll()
      Returns the next available reference from the queue if one is enqueued, null otherwise. Does not wait for a reference to become available.
      Returns:
      Reference next available Reference or NULL.
    • remove

      public Reference<? extends T> remove() throws InterruptedException
      Return the next available enqueued reference on the queue, blocking indefinitely until one is available.
      Returns:
      Reference a Reference object if one is available, null otherwise.
      Throws:
      InterruptedException - to interrupt the wait.
    • remove

      public Reference<? extends T> remove(long timeout) throws IllegalArgumentException, InterruptedException
      Return the next available enqueued reference on the queue, blocking up to the time given until one is available. Return null if no reference became available.
      Parameters:
      timeout - maximum time spent waiting for a reference object to become available.
      Returns:
      Reference a Reference object if one is available, null otherwise.
      Throws:
      IllegalArgumentException - if the wait period is negative.
      InterruptedException - to interrupt the wait.