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 org.apache.camel.Exchange;
020 import org.apache.camel.Processor;
021 import org.apache.camel.impl.ServiceSupport;
022 import org.apache.camel.spi.Policy;
023 import org.apache.camel.util.ServiceHelper;
024
025 /**
026 * A Delegate pattern which delegates processing to a nested processor which can
027 * be useful for implementation inheritance when writing an {@link Policy}
028 *
029 * @version $Revision: 519941 $
030 */
031 public class DelegateProcessor extends ServiceSupport implements Processor {
032 private Processor processor;
033
034 public DelegateProcessor() {
035 }
036
037 public DelegateProcessor(Processor processor) {
038 this.processor = processor;
039 }
040
041 public void process(Exchange exchange) throws Exception {
042 processNext(exchange);
043 }
044
045 protected void processNext(Exchange exchange) throws Exception {
046 if (processor != null) {
047 processor.process(exchange);
048 }
049 }
050
051 @Override
052 public String toString() {
053 return "Delegate(" + processor + ")";
054 }
055
056 public Processor getProcessor() {
057 return processor;
058 }
059
060 public void setProcessor(Processor processor) {
061 this.processor = processor;
062 }
063
064 protected void doStart() throws Exception {
065 ServiceHelper.startServices(processor);
066 }
067
068 protected void doStop() throws Exception {
069 ServiceHelper.stopServices(processor);
070 }
071
072 /**
073 * Proceed with the underlying delegated processor
074 */
075 public void proceed(Exchange exchange) throws Exception {
076 processNext(exchange);
077 }
078 }