--- projects/cms/source/util/uk/org/iscream/cms/util/Queue.java	2001/03/01 01:05:49	1.14
+++ projects/cms/source/util/uk/org/iscream/cms/util/Queue.java	2001/03/26 17:59:47	1.20
@@ -1,11 +1,11 @@
 //---PACKAGE DECLARATION---
-package uk.ac.ukc.iscream.util;
+package uk.org.iscream.util;
 
 //---IMPORTS---
 import java.util.LinkedList;
 import java.util.NoSuchElementException;
 import java.util.Random;
-import uk.ac.ukc.iscream.util.*;
+import uk.org.iscream.util.*;
 
 /**
  * A Queue class designed to operate in a multi-threaded environment, with
@@ -14,7 +14,7 @@ import uk.ac.ukc.iscream.util.*;
  * actually contains some elements.
  *
  * @author  $Author: tdb $
- * @version $Id: Queue.java,v 1.14 2001/03/01 01:05:49 tdb Exp $
+ * @version $Id: Queue.java,v 1.20 2001/03/26 17:59:47 tdb Exp $
  */
 public class Queue {
 
@@ -23,7 +23,7 @@ public class Queue {
     /**
      * The current CVS revision of this class
      */
-    public static final String REVISION = "$Revision: 1.14 $";
+    public static final String REVISION = "$Revision: 1.20 $";
     
     /**
      * Pass to constructor to remove a RANDOM item from
@@ -49,6 +49,11 @@ public class Queue {
      */
     public static final int DROP = 3;
     
+    /**
+     * To allow opposite lookups.
+     */
+    public static final String[] algorithms = {"RANDOM", "FIRST", "LAST", "DROP"};
+    
 //---STATIC METHODS---
 
 //---CONSTRUCTORS---  
@@ -92,12 +97,12 @@ public class Queue {
                 // get size before adding to the Queue
                 int s = ((LinkedList) _lists.get(i)).size();
                 // check whether we need to remove an item from the current Queue
-                if(_maxSize!=-1 && s==_maxSize && _removeAlgorithm!=DROP) {
+                if(_maxSize!=-1 && s>=_maxSize && _removeAlgorithm!=DROP) {
                     // we need to remove an item
                     removeQueueItem((LinkedList) _lists.get(i));
                 }
                 // check if we should add (not if Queue full, and using DROP algorithm)
-                if(!(s==_maxSize && _removeAlgorithm==DROP)) {
+                if(!(s>=_maxSize && _removeAlgorithm==DROP)) {
                     // add the next item, ensuring we lock
                     synchronized(this) {
                         // LinkedList.add() does the same thing, but this ensures behaviour
@@ -106,10 +111,8 @@ public class Queue {
                 }
                 // if the queue was empty before the add it is possible
                 // that a consumer is waiting... so we notify them
-                if (s == 0) {
-                    synchronized(((LinkedList) _lists.get(i))) {
-                        ((LinkedList) _lists.get(i)).notifyAll();
-                    }
+                synchronized(((LinkedList) _lists.get(i))) {
+                    ((LinkedList) _lists.get(i)).notifyAll();
                 }
             }
         }
@@ -131,8 +134,8 @@ public class Queue {
             throw new InvalidQueueException("Requested queue "+queue+" does not exist");
         }
         // block if the queue is empty
-        if (((LinkedList) _lists.get(queue)).size() == 0) {
-            synchronized(((LinkedList) _lists.get(queue))) {
+        synchronized(((LinkedList) _lists.get(queue))) {
+            if (((LinkedList) _lists.get(queue)).size() == 0) {
                 try { ((LinkedList) _lists.get(queue)).wait(); } catch(Exception e) {}
             }
         }
@@ -201,7 +204,7 @@ public class Queue {
         if(_maxSize != -1) {
             status += " maxSize=\""+_maxSize+"\"";
         }
-        status += "</queue>";
+        status += "></queue>";
         return status;
     }
     
@@ -242,7 +245,7 @@ public class Queue {
      *
      * @return An integer to be passed to the get() method.
      */
-    public int getQueue() {
+    public synchronized int getQueue() {
         int pos = -1;
         for(int i=0; i < _lists.size(); i++) {
             if(_lists.get(i) == null) {
@@ -266,7 +269,7 @@ public class Queue {
      *
      * @param queue The integer identifier for the queue, given by getQueue().
      */
-    public void removeQueue(int queue) {
+    public synchronized void removeQueue(int queue) {
         _lists.set(queue, null);
     }
     
@@ -327,7 +330,7 @@ public class Queue {
      * Overrides the {@link java.lang.Object#toString() Object.toString()}
      * method to provide clean logging (every class should have this).
      *
-     * This uses the uk.ac.ukc.iscream.util.FormatName class
+     * This uses the uk.org.iscream.util.FormatName class
      * to format the toString()
      *
      * @return the name of this class and its CVS revision.