001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.camel.processor;
018
019 import java.util.Comparator;
020 import java.util.List;
021 import java.util.Set;
022 import java.util.TreeSet;
023
024 import org.apache.camel.Endpoint;
025 import org.apache.camel.Exchange;
026 import org.apache.camel.Expression;
027 import org.apache.camel.Processor;
028 import org.apache.camel.util.ExpressionComparator;
029 import org.apache.camel.util.ExpressionListComparator;
030
031 /**
032 * An implementation of the <a href="http://activemq.apache.org/camel/resequencer.html">Resequencer</a>
033 * which can reorder messages within a batch.
034 *
035 * @version $Revision: 630591 $
036 */
037 public class Resequencer extends BatchProcessor {
038 public Resequencer(Endpoint endpoint, Processor processor, Expression<Exchange> expression) {
039 this(endpoint, processor, createSet(expression));
040 }
041
042 public Resequencer(Endpoint endpoint, Processor processor, List<Expression> expressions) {
043 this(endpoint, processor, createSet(expressions));
044 }
045
046 public Resequencer(Endpoint endpoint, Processor processor, Set<Exchange> collection) {
047 super(endpoint, processor, collection);
048 }
049
050 @Override
051 public String toString() {
052 return "Resequencer[to: " + getProcessor() + "]";
053 }
054
055 // Implementation methods
056 //-------------------------------------------------------------------------
057
058 protected static Set<Exchange> createSet(Expression<Exchange> expression) {
059 return createSet(new ExpressionComparator<Exchange>(expression));
060 }
061
062 protected static Set<Exchange> createSet(List<Expression> expressions) {
063 if (expressions.size() == 1) {
064 return createSet(expressions.get(0));
065 }
066 return createSet(new ExpressionListComparator(expressions));
067 }
068
069 protected static Set<Exchange> createSet(Comparator<? super Exchange> comparator) {
070 return new TreeSet<Exchange>(comparator);
071 }
072 }