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.concurrent.Callable;
020 import java.util.concurrent.ExecutorService;
021
022 import org.apache.camel.AsyncCallback;
023 import org.apache.camel.AsyncProcessor;
024 import org.apache.camel.CamelContext;
025 import org.apache.camel.Exchange;
026 import org.apache.camel.ExchangePattern;
027 import org.apache.camel.Message;
028 import org.apache.camel.Ordered;
029 import org.apache.camel.Predicate;
030 import org.apache.camel.Processor;
031 import org.apache.camel.Traceable;
032 import org.apache.camel.support.ServiceSupport;
033 import org.apache.camel.support.SynchronizationAdapter;
034 import org.apache.camel.util.AsyncProcessorHelper;
035 import org.apache.camel.util.ExchangeHelper;
036 import org.apache.camel.util.ServiceHelper;
037 import org.slf4j.Logger;
038 import org.slf4j.LoggerFactory;
039
040 import static org.apache.camel.util.ObjectHelper.notNull;
041
042 /**
043 * @version
044 */
045 public class OnCompletionProcessor extends ServiceSupport implements AsyncProcessor, Traceable {
046
047 private static final Logger LOG = LoggerFactory.getLogger(OnCompletionProcessor.class);
048 private final CamelContext camelContext;
049 private final Processor processor;
050 private final ExecutorService executorService;
051 private final boolean shutdownExecutorService;
052 private final boolean onCompleteOnly;
053 private final boolean onFailureOnly;
054 private final Predicate onWhen;
055 private final boolean useOriginalBody;
056
057 public OnCompletionProcessor(CamelContext camelContext, Processor processor, ExecutorService executorService, boolean shutdownExecutorService,
058 boolean onCompleteOnly, boolean onFailureOnly, Predicate onWhen, boolean useOriginalBody) {
059 notNull(camelContext, "camelContext");
060 notNull(processor, "processor");
061 this.camelContext = camelContext;
062 this.processor = processor;
063 this.executorService = executorService;
064 this.shutdownExecutorService = shutdownExecutorService;
065 this.onCompleteOnly = onCompleteOnly;
066 this.onFailureOnly = onFailureOnly;
067 this.onWhen = onWhen;
068 this.useOriginalBody = useOriginalBody;
069 }
070
071 @Override
072 protected void doStart() throws Exception {
073 ServiceHelper.startService(processor);
074 }
075
076 @Override
077 protected void doStop() throws Exception {
078 ServiceHelper.stopService(processor);
079 }
080
081 @Override
082 protected void doShutdown() throws Exception {
083 ServiceHelper.stopAndShutdownService(processor);
084 if (shutdownExecutorService) {
085 getCamelContext().getExecutorServiceManager().shutdownNow(executorService);
086 }
087 }
088
089 public CamelContext getCamelContext() {
090 return camelContext;
091 }
092
093 public void process(Exchange exchange) throws Exception {
094 AsyncProcessorHelper.process(this, exchange);
095 }
096
097 public boolean process(Exchange exchange, AsyncCallback callback) {
098 if (processor != null) {
099 // register callback
100 exchange.getUnitOfWork().addSynchronization(new OnCompletionSynchronization());
101 }
102
103 callback.done(true);
104 return true;
105 }
106
107 /**
108 * Processes the exchange by the processors
109 *
110 * @param processor the processor
111 * @param exchange the exchange
112 */
113 protected static void doProcess(Processor processor, Exchange exchange) {
114 try {
115 processor.process(exchange);
116 } catch (Exception e) {
117 exchange.setException(e);
118 }
119 }
120
121 /**
122 * Prepares the {@link Exchange} to send as onCompletion.
123 *
124 * @param exchange the current exchange
125 * @return the exchange to be routed in onComplete
126 */
127 protected Exchange prepareExchange(Exchange exchange) {
128 Exchange answer;
129
130 // for asynchronous routing we must use a copy as we dont want it
131 // to cause side effects of the original exchange
132 // (the original thread will run in parallel)
133 answer = ExchangeHelper.createCorrelatedCopy(exchange, false);
134 if (answer.hasOut()) {
135 // move OUT to IN (pipes and filters)
136 answer.setIn(answer.getOut());
137 answer.setOut(null);
138 }
139 // set MEP to InOnly as this wire tap is a fire and forget
140 answer.setPattern(ExchangePattern.InOnly);
141
142 if (useOriginalBody) {
143 LOG.trace("Using the original IN message instead of current");
144
145 Message original = exchange.getUnitOfWork().getOriginalInMessage();
146 answer.setIn(original);
147 }
148
149 // add a header flag to indicate its a on completion exchange
150 answer.setProperty(Exchange.ON_COMPLETION, Boolean.TRUE);
151
152 return answer;
153 }
154
155 private final class OnCompletionSynchronization extends SynchronizationAdapter implements Ordered {
156
157 public int getOrder() {
158 // we want to be last
159 return Ordered.LOWEST;
160 }
161
162 @Override
163 public void onComplete(final Exchange exchange) {
164 if (onFailureOnly) {
165 return;
166 }
167
168 if (onWhen != null && !onWhen.matches(exchange)) {
169 // predicate did not match so do not route the onComplete
170 return;
171 }
172
173 // must use a copy as we dont want it to cause side effects of the original exchange
174 final Exchange copy = prepareExchange(exchange);
175
176 executorService.submit(new Callable<Exchange>() {
177 public Exchange call() throws Exception {
178 LOG.debug("Processing onComplete: {}", copy);
179 doProcess(processor, copy);
180 return copy;
181 }
182 });
183 }
184
185 public void onFailure(final Exchange exchange) {
186 if (onCompleteOnly) {
187 return;
188 }
189
190 if (onWhen != null && !onWhen.matches(exchange)) {
191 // predicate did not match so do not route the onComplete
192 return;
193 }
194
195 // must use a copy as we dont want it to cause side effects of the original exchange
196 final Exchange copy = prepareExchange(exchange);
197 // must remove exception otherwise onFailure routing will fail as well
198 // the caused exception is stored as a property (Exchange.EXCEPTION_CAUGHT) on the exchange
199 copy.setException(null);
200
201 executorService.submit(new Callable<Exchange>() {
202 public Exchange call() throws Exception {
203 LOG.debug("Processing onFailure: {}", copy);
204 doProcess(processor, copy);
205 return null;
206 }
207 });
208 }
209
210 @Override
211 public String toString() {
212 if (!onCompleteOnly && !onFailureOnly) {
213 return "onCompleteOrFailure";
214 } else if (onCompleteOnly) {
215 return "onCompleteOnly";
216 } else {
217 return "onFailureOnly";
218 }
219 }
220 }
221
222 @Override
223 public String toString() {
224 return "OnCompletionProcessor[" + processor + "]";
225 }
226
227 public String getTraceLabel() {
228 return "onCompletion";
229 }
230 }