org.apache.qpid.client.util

Class FlowControllingBlockingQueue

java.lang.Object

org.apache.qpid.client.util.FlowControllingBlockingQueue

public class FlowControllingBlockingQueue
extends Object

A blocking queue that emits events above a user specified threshold allowing the caller to take action (e.g. flow control) to try to prevent the queue growing (much) further. The underlying queue itself is not bounded therefore the caller is not obliged to react to the events.

This implementation is only safe where we have a single thread adding items and a single (different) thread removing items.

TODO Make this implement java.util.Queue and hide the implementation. Then different queue types can be substituted.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	FlowControllingBlockingQueue.ThresholdListener

Constructor Summary

Constructors

Constructor and Description
FlowControllingBlockingQueue(int threshold, FlowControllingBlockingQueue.ThresholdListener listener)
FlowControllingBlockingQueue(int highThreshold, int lowThreshold, FlowControllingBlockingQueue.ThresholdListener listener)

Method Summary

Methods

Modifier and Type	Method and Description
void	add(Object o)
boolean	isEmpty()
Iterator	iterator()
Object	take()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FlowControllingBlockingQueue

public FlowControllingBlockingQueue(int threshold,
                            FlowControllingBlockingQueue.ThresholdListener listener)

FlowControllingBlockingQueue

public FlowControllingBlockingQueue(int highThreshold,
                            int lowThreshold,
                            FlowControllingBlockingQueue.ThresholdListener listener)

Method Detail

isEmpty

public boolean isEmpty()

take

public Object take()
            throws InterruptedException

Throws:

InterruptedException

add

public void add(Object o)

iterator

public Iterator iterator()