added a helper method so a BrokerFilter can lookup all the active destinations for a specific wildcard which can be useful for implementing things like AMQ-452 to support virtual destinations

git-svn-id: https://svn.apache.org/repos/asf/incubator/activemq/trunk@419629 13f79535-47bb-0310-9956-ffa450edef68

activemq-core/src/main/java/org/apache/activemq/broker/BrokerFilter.java

@@ -16,8 +16,6 @@
  */
 package org.apache.activemq.broker;
 
-import java.util.Map;
-import java.util.Set;
 import org.apache.activemq.broker.region.Destination;
 import org.apache.activemq.broker.region.Subscription;
 import org.apache.activemq.command.ActiveMQDestination;
@@ -35,6 +33,9 @@ import org.apache.activemq.command.RemoveSubscriptionInfo;
 import org.apache.activemq.command.SessionInfo;
 import org.apache.activemq.command.TransactionId;
 
+import java.util.Map;
+import java.util.Set;
+
 /**
  * Allows you to intercept broker operation so that features such as security can be 
  * implemented as a pluggable filter.
@@ -49,7 +50,6 @@ public class BrokerFilter implements Broker {
         this.next=next;
     }
    
-   
     public Broker getAdaptor(Class type){
         if (type.isInstance(this)){
             return this;
@@ -61,6 +61,10 @@ public class BrokerFilter implements Broker {
         return next.getDestinationMap();
     }
 
+    public Set getDestinations(ActiveMQDestination destination) {
+        return next.getDestinations(destination);
+    }
+
     public void acknowledge(ConnectionContext context, MessageAck ack) throws Exception {
         next.acknowledge(context, ack);
     }

activemq-core/src/main/java/org/apache/activemq/broker/EmptyBroker.java

@@ -16,9 +16,6 @@
  */
 package org.apache.activemq.broker;
 
-import java.util.Collections;
-import java.util.Map;
-import java.util.Set;
 import org.apache.activemq.broker.region.Destination;
 import org.apache.activemq.broker.region.Subscription;
 import org.apache.activemq.command.ActiveMQDestination;
@@ -36,6 +33,10 @@ import org.apache.activemq.command.RemoveSubscriptionInfo;
 import org.apache.activemq.command.SessionInfo;
 import org.apache.activemq.command.TransactionId;
 
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
+
 /**
  * Dumb implementation - used to be overriden by listeners
  * 
@@ -62,6 +63,10 @@ public class EmptyBroker implements Broker{
         return Collections.EMPTY_MAP;
     }
 
+    public Set getDestinations(ActiveMQDestination destination) {
+        return Collections.EMPTY_SET;
+    }
+
     public void addConnection(ConnectionContext context,ConnectionInfo info) throws Exception{
 
     }

activemq-core/src/main/java/org/apache/activemq/broker/ErrorBroker.java

@@ -54,6 +54,10 @@ public class ErrorBroker implements Broker {
         return Collections.EMPTY_MAP;
     }
 
+    public Set getDestinations(ActiveMQDestination destination) {
+        return Collections.EMPTY_SET;
+    }
+
     public Broker getAdaptor(Class type){
         if (type.isInstance(this)){
             return this;

activemq-core/src/main/java/org/apache/activemq/broker/MutableBrokerFilter.java

@@ -16,8 +16,6 @@
  */
 package org.apache.activemq.broker;
 
-import java.util.Map;
-import java.util.Set;
 import org.apache.activemq.broker.region.Destination;
 import org.apache.activemq.broker.region.Subscription;
 import org.apache.activemq.command.ActiveMQDestination;
@@ -35,6 +33,9 @@ import org.apache.activemq.command.RemoveSubscriptionInfo;
 import org.apache.activemq.command.SessionInfo;
 import org.apache.activemq.command.TransactionId;
 
+import java.util.Map;
+import java.util.Set;
+
 /**
  * Like a BrokerFilter but it allows you to switch the getNext().broker.  This has more 
  * overhead than a BrokerFilter since access to the getNext().broker has to synchronized
@@ -74,6 +75,10 @@ public class MutableBrokerFilter implements Broker {
         return getNext().getDestinationMap();
     }
 
+    public Set getDestinations(ActiveMQDestination destination) {
+        return getNext().getDestinations(destination);
+    }
+
     public void acknowledge(ConnectionContext context, MessageAck ack) throws Exception {
         getNext().acknowledge(context, ack);
     }

activemq-core/src/main/java/org/apache/activemq/broker/region/AbstractRegion.java

@@ -134,6 +134,17 @@ abstract public class AbstractRegion implements Region {
         }
     }
     
+    /**
+     * Provide an exact or wildcard lookup of destinations in the region
+     * 
+     * @return a set of matching destination objects.
+     */
+    public Set getDestinations(ActiveMQDestination destination) {
+        synchronized(destinationsMutex){
+            return destinationMap.get(destination);
+        }
+    }
+    
     public Map getDestinationMap() {
         synchronized(destinationsMutex){
             return new HashMap(destinations);

activemq-core/src/main/java/org/apache/activemq/broker/region/Region.java

@@ -26,6 +26,7 @@ import org.apache.activemq.command.MessageDispatchNotification;
 import org.apache.activemq.command.RemoveSubscriptionInfo;
 
 import java.util.Map;
+import java.util.Set;
 
 /**
  * A Region is used to implement the different QOS options available to 
@@ -115,4 +116,11 @@ public interface Region extends Service {
 
     public void gc();
 
+    /**
+     * Provide an exact or wildcard lookup of destinations in the region
+     * 
+     * @return a set of matching destination objects.
+     */
+    public Set getDestinations(ActiveMQDestination destination);
+    
 }

activemq-core/src/main/java/org/apache/activemq/broker/region/RegionBroker.java

@@ -103,6 +103,21 @@ public class RegionBroker implements Broker {
         return answer;
     }
 
+    public Set getDestinations(ActiveMQDestination destination) {
+        switch(destination.getDestinationType()) {
+        case ActiveMQDestination.QUEUE_TYPE:
+            return queueRegion.getDestinations(destination);
+        case ActiveMQDestination.TOPIC_TYPE:
+            return topicRegion.getDestinations(destination);
+        case ActiveMQDestination.TEMP_QUEUE_TYPE:
+            return tempQueueRegion.getDestinations(destination);
+        case ActiveMQDestination.TEMP_TOPIC_TYPE:
+            return tempTopicRegion.getDestinations(destination);
+        default:
+            return Collections.EMPTY_SET;
+        }
+    }
+
     public Broker getAdaptor(Class type){
         if (type.isInstance(this)){
             return this;