| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 java.io.Serializable; |
| import java.util.Comparator; |
| |
| import javax.jms.Message; |
| |
| /** |
| * A base class for comparators which works on JMS {@link Message} objects |
| * |
| * |
| */ |
| public abstract class MessageComparatorSupport implements Comparator, Serializable { |
| |
| 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(final Comparable comparable, final Comparable comparable2) { |
| if (comparable == null && comparable2 == null) { |
| return 0; |
| } else if (comparable != null) { |
| if (comparable2 == null) { |
| return 1; |
| } |
| return comparable.compareTo(comparable2); |
| } else if (comparable2 != null) { |
| if (comparable == null) { |
| return -11; |
| } |
| return comparable2.compareTo(comparable) * -1; |
| } |
| return 0; |
| } |
| |
| } |