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.Collection;
021    import java.util.List;
022    
023    import org.apache.camel.Exchange;
024    import org.apache.camel.Navigate;
025    import org.apache.camel.Processor;
026    import org.apache.camel.impl.ServiceSupport;
027    import org.apache.camel.util.ServiceHelper;
028    
029    /**
030     * Represents a composite pattern, aggregating a collection of processors
031     * together as a single processor
032     * 
033     * @version $Revision: 769303 $
034     */
035    public class CompositeProcessor extends ServiceSupport implements Processor, Navigate<Processor> {
036        private final Collection<Processor> processors;
037    
038        public CompositeProcessor(Collection<Processor> processors) {
039            this.processors = processors;
040        }
041    
042        public void process(Exchange exchange) throws Exception {
043            for (Processor processor : processors) {
044                processor.process(exchange);
045            }
046        }
047    
048        @Override
049        public String toString() {
050            StringBuilder builder = new StringBuilder("[ ");
051            boolean first = true;
052            for (Processor processor : processors) {
053                if (first) {
054                    first = false;
055                } else {
056                    builder.append(", ");
057                }
058                builder.append(processor.toString());
059            }
060            builder.append(" ]");
061            return builder.toString();
062        }
063    
064        public Collection<Processor> getProcessors() {
065            return processors;
066        }
067    
068        public List<Processor> next() {
069            if (!hasNext()) {
070                return null;
071            }
072            return new ArrayList<Processor>(processors);
073        }
074    
075        public boolean hasNext() {
076            return processors != null && !processors.isEmpty();
077        }
078    
079        protected void doStart() throws Exception {
080            ServiceHelper.startServices(processors);
081        }
082    
083        protected void doStop() throws Exception {
084            ServiceHelper.stopServices(processors);
085        }
086    }