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//---PACKAGE DECLARATION--- |
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package uk.ac.ukc.iscream.util; |
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//---IMPORTS--- |
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import java.util.LinkedList; |
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import java.util.NoSuchElementException; |
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//import uk.ac.ukc.iscream.util.*; |
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import uk.ac.ukc.iscream.util.*; |
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/** |
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* A Queue class designed to operate in a multi-threaded environment, with |
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* @author $Author$ |
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* @version $Id$ |
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*/ |
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class Queue { |
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public class Queue { |
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//---FINAL ATTRIBUTES--- |
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} |
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return o; |
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} |
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/** |
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* This method releases a get() method that's currently |
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* waiting on an empty queue. This was designed for |
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* shutdown() type methods that may have problems closing |
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* if the thread of control is waiting on a queue. |
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* |
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* @param queue the queue to release |
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*/ |
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public void releaseQueue(int queue) { |
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synchronized(((LinkedList) _lists.get(queue))) { |
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((LinkedList) _lists.get(queue)).notifyAll(); |
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} |
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} |
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/** |
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* This method returns a textual status of the queues. It |
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* is merely for observation, and would most likely be used |
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* by a larger "monitoring" component. Information returned |
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} |
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/** |
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* Returns the size of a given queue. A consumer can use |
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* this to see how big their queue is at any given time. |
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* they should use their queue number as the parameter. |
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* |
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* @param queue The queue number to query. |
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* @return the current size of the queue. |
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*/ |
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public int queueSize(int queue) throws InvalidQueueException { |
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if (queue >= _lists.size() || _lists.get(queue) == null) { |
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throw new InvalidQueueException("Requested queue "+queue+" does not exist"); |
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} |
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return ((LinkedList) _lists.get(queue)).size(); |
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} |
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/** |
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* Returns the total numer of elements to have passed |
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* through this queue (ie. a counter on the add method). |
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* |
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* @return the element-ometer |
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*/ |
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public int elementCount() { |
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return _count; |
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} |
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/** |
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* This method assigns a queue to a consumer. The idea behind |
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* this is to ensure that only 1 consumer can be associated with |
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* a given queue, otherwise the whole "blocking" thing fails |
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* |
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* @return the name of this class and its CVS revision |
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*/ |
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/*public String toString() { |
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public String toString() { |
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return FormatName.getName( |
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_name, |
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getClass().getName(), |
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REVISION); |
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}*/ |
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} |
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//---PRIVATE METHODS--- |
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* can be placed here. This name could also |
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* be changed to null for utility classes. |
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*/ |
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//private String _name = <!THIS SHOULD CALL A STATIC NAME IN THE COMPONENT CLASS FOR THIS OBJECT!>; |
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/** |
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* This holds a reference to the |
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* system logger that is being used. |
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*/ |
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//private Logger _logger = ReferenceManager.getInstance().getLogger(); |
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private String _name = null; |
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//---STATIC ATTRIBUTES--- |
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