001 /**
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one or more
004 * contributor license agreements. See the NOTICE file distributed with
005 * this work for additional information regarding copyright ownership.
006 * The ASF licenses this file to You under the Apache License, Version 2.0
007 * (the "License"); you may not use this file except in compliance with
008 * the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.apache.camel.processor;
019
020 import org.apache.camel.Predicate;
021 import org.apache.camel.Processor;
022 import org.apache.camel.Exchange;
023 import org.apache.camel.util.ServiceHelper;
024 import org.apache.camel.impl.ServiceSupport;
025
026 import java.util.ArrayList;
027 import java.util.List;
028
029 /**
030 * Implements a Choice structure where one or more predicates are used which if they are true their processors
031 * are used, with a default otherwise clause used if none match.
032 *
033 * @version $Revision: 534145 $
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 }
065 else {
066 builder.append(", ");
067 }
068 builder.append("when ");
069 builder.append(processor.getPredicate().toString());
070 builder.append(": ");
071 builder.append(processor.getProcessor());
072 }
073 if (otherwise != null) {
074 builder.append(", otherwise: ");
075 builder.append(otherwise);
076 }
077 builder.append("}");
078 return builder.toString();
079 }
080
081 public List<FilterProcessor> getFilters() {
082 return filters;
083 }
084
085 public Processor getOtherwise() {
086 return otherwise;
087 }
088
089
090 protected void doStart() throws Exception {
091 ServiceHelper.startServices(filters);
092 ServiceHelper.startServices(otherwise);
093 }
094
095 protected void doStop() throws Exception {
096 ServiceHelper.stopServices(otherwise);
097 ServiceHelper.stopServices(filters);
098 }
099 }