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.ArrayList;
020 import java.util.List;
021
022 import org.apache.camel.Exchange;
023 import org.apache.camel.Predicate;
024 import org.apache.camel.Processor;
025 import org.apache.camel.impl.ServiceSupport;
026 import org.apache.camel.util.ServiceHelper;
027
028 /**
029 * Implements a Choice structure where one or more predicates are used which if
030 * they are true their processors are used, with a default otherwise clause used
031 * if none match.
032 *
033 * @version $Revision: 563607 $
034 */
035 public class ChoiceProcessor extends ServiceSupport implements Processor {
036 private List<FilterProcessor> filters = new ArrayList<FilterProcessor>();
037 private Processor otherwise;
038
039 public ChoiceProcessor(List<FilterProcessor> filters, Processor otherwise) {
040 this.filters = filters;
041 this.otherwise = otherwise;
042 }
043
044 public void process(Exchange exchange) throws Exception {
045 for (FilterProcessor filterProcessor : filters) {
046 Predicate<Exchange> predicate = filterProcessor.getPredicate();
047 if (predicate != null && predicate.matches(exchange)) {
048 filterProcessor.getProcessor().process(exchange);
049 return;
050 }
051 }
052 if (otherwise != null) {
053 otherwise.process(exchange);
054 }
055 }
056
057 @Override
058 public String toString() {
059 StringBuilder builder = new StringBuilder("choice{");
060 boolean first = true;
061 for (FilterProcessor processor : filters) {
062 if (first) {
063 first = false;
064 } else {
065 builder.append(", ");
066 }
067 builder.append("when ");
068 builder.append(processor.getPredicate().toString());
069 builder.append(": ");
070 builder.append(processor.getProcessor());
071 }
072 if (otherwise != null) {
073 builder.append(", otherwise: ");
074 builder.append(otherwise);
075 }
076 builder.append("}");
077 return builder.toString();
078 }
079
080 public List<FilterProcessor> getFilters() {
081 return filters;
082 }
083
084 public Processor getOtherwise() {
085 return otherwise;
086 }
087
088 protected void doStart() throws Exception {
089 ServiceHelper.startServices(filters);
090 ServiceHelper.startServices(otherwise);
091 }
092
093 protected void doStop() throws Exception {
094 ServiceHelper.stopServices(otherwise);
095 ServiceHelper.stopServices(filters);
096 }
097 }