added helper classes for comparing messages

git-svn-id: https://svn.apache.org/repos/asf/incubator/activemq/trunk@396891 13f79535-47bb-0310-9956-ffa450edef68

activemq-core/src/main/java/org/apache/activemq/util/MessageComparatorSupport.java

@@ -0,0 +1,48 @@
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.activemq.util;
+
+import javax.jms.Message;
+
+import java.util.Comparator;
+
+/**
+ * A base class for comparators which works on JMS {@link Message} objects
+ * 
+ * @version $Revision$
+ */
+public abstract class MessageComparatorSupport implements Comparator {
+
+    public int compare(Object object1, Object object2) {
+        Message command1 = (Message) object1;
+        Message command2 = (Message) object2;
+        return compareMessages(command1, command2);
+    }
+
+    protected abstract int compareMessages(Message message1, Message message2);
+
+    protected int compareComparators(Comparable comparable, Comparable comparable2) {
+        if (comparable != null) {
+            return comparable.compareTo(comparable2);
+        }
+        else if (comparable2 != null) {
+            return comparable2.compareTo(comparable) * -1;
+        }
+        return 0;
+    }
+
+}

activemq-core/src/main/java/org/apache/activemq/util/MessageDestinationComparator.java

@@ -0,0 +1,56 @@
+/**
+ *
+ * Copyright 2005-2006 The Apache Software Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.activemq.util;
+
+import org.apache.activemq.command.ActiveMQMessage;
+
+import javax.jms.*;
+
+/**
+ * A comparator which works on SendCommand objects to compare the destinations
+ * 
+ * @version $Revision$
+ */
+public class MessageDestinationComparator extends MessageComparatorSupport {
+
+    protected int compareMessages(Message message1, Message message2) {
+        return compareComparators(getComparable(getDestination(message1)), getComparable(getDestination(message2)));
+    }
+
+    protected Destination getDestination(Message message) {
+        if (message instanceof ActiveMQMessage) {
+            ActiveMQMessage amqMessage = (ActiveMQMessage) message;
+            return amqMessage.getDestination();
+        }
+        try {
+            return message.getJMSDestination();
+        }
+        catch (JMSException e) {
+            return null;
+        }
+    }
+
+    protected Comparable getComparable(Destination destination) {
+        if (destination != null) {
+            return destination.toString();
+        }
+        return null;
+    }
+
+
+    
+}