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.impl;
018
019 import java.util.ArrayList;
020 import java.util.Iterator;
021 import java.util.List;
022 import java.util.Map;
023 import java.util.concurrent.ConcurrentHashMap;
024
025 import org.apache.camel.CamelContext;
026 import org.apache.camel.Endpoint;
027 import org.apache.camel.Exchange;
028 import org.apache.camel.ExchangePattern;
029 import org.apache.camel.Message;
030 import org.apache.camel.spi.Synchronization;
031 import org.apache.camel.spi.UnitOfWork;
032 import org.apache.camel.util.ExchangeHelper;
033 import org.apache.camel.util.ObjectHelper;
034 import org.apache.camel.util.UuidGenerator;
035
036 /**
037 * A default implementation of {@link Exchange}
038 *
039 * @version $Revision: 777808 $
040 */
041 public class DefaultExchange implements Exchange {
042
043 private static final UuidGenerator DEFAULT_ID_GENERATOR = new UuidGenerator();
044 protected final CamelContext context;
045 private Map<String, Object> properties;
046 private Message in;
047 private Message out;
048 private Message fault;
049 private Exception exception;
050 private String exchangeId;
051 private UnitOfWork unitOfWork;
052 private ExchangePattern pattern;
053 private Endpoint fromEndpoint;
054 private List<Synchronization> onCompletions;
055
056 public DefaultExchange(CamelContext context) {
057 this(context, ExchangePattern.InOnly);
058 }
059
060 public DefaultExchange(CamelContext context, ExchangePattern pattern) {
061 this.context = context;
062 this.pattern = pattern;
063 }
064
065 public DefaultExchange(Exchange parent) {
066 this(parent.getContext(), parent.getPattern());
067 this.unitOfWork = parent.getUnitOfWork();
068 this.fromEndpoint = parent.getFromEndpoint();
069 }
070
071 public DefaultExchange(Endpoint fromEndpoint) {
072 this(fromEndpoint, ExchangePattern.InOnly);
073 }
074
075 public DefaultExchange(Endpoint fromEndpoint, ExchangePattern pattern) {
076 this.context = fromEndpoint.getCamelContext();
077 this.fromEndpoint = fromEndpoint;
078 this.pattern = pattern;
079 }
080
081 @Override
082 public String toString() {
083 return "Exchange[" + in + "]";
084 }
085
086 public Exchange copy() {
087 Exchange exchange = newInstance();
088 exchange.copyFrom(this);
089 return exchange;
090 }
091
092 public Exchange newCopy(boolean handoverOnCompletion) {
093 Exchange copy = copy();
094 // do not share the unit of work
095 copy.setUnitOfWork(null);
096 // handover on completeion to the copy if we got any
097 if (handoverOnCompletion && unitOfWork != null) {
098 unitOfWork.handoverSynchronization(copy);
099 }
100 return copy;
101 }
102
103 public void copyFrom(Exchange exchange) {
104 if (exchange == this) {
105 return;
106 }
107 setProperties(safeCopy(exchange.getProperties()));
108
109 // this can cause strangeness if we copy, say, a FileMessage onto an FtpExchange with overloaded getExchange() methods etc.
110 safeCopy(getIn(), exchange.getIn());
111 if (exchange.hasOut()) {
112 safeCopy(getOut(), exchange.getOut());
113 }
114 if (exchange.hasFault()) {
115 safeCopy(getFault(), exchange.getFault());
116 }
117 setException(exchange.getException());
118
119 unitOfWork = exchange.getUnitOfWork();
120 pattern = exchange.getPattern();
121 setFromEndpoint(exchange.getFromEndpoint());
122 }
123
124 private static void safeCopy(Message message, Message that) {
125 if (message != null) {
126 message.copyFrom(that);
127 }
128 }
129
130 private static Map<String, Object> safeCopy(Map<String, Object> properties) {
131 if (properties == null) {
132 return null;
133 }
134 return new ConcurrentHashMap<String, Object>(properties);
135 }
136
137 public Exchange newInstance() {
138 return new DefaultExchange(this);
139 }
140
141 public CamelContext getContext() {
142 return context;
143 }
144
145 public Object getProperty(String name) {
146 if (properties != null) {
147 return properties.get(name);
148 }
149 return null;
150 }
151
152 public <T> T getProperty(String name, Class<T> type) {
153 Object value = getProperty(name);
154 return ExchangeHelper.convertToType(this, type, value);
155 }
156
157 public void setProperty(String name, Object value) {
158 if (value != null) {
159 // avoid the NullPointException
160 getProperties().put(name, value);
161 } else {
162 // if the value is null, we just remove the key from the map
163 if (name != null) {
164 getProperties().remove(name);
165 }
166 }
167 }
168
169 public Object removeProperty(String name) {
170 return getProperties().remove(name);
171 }
172
173 public Map<String, Object> getProperties() {
174 if (properties == null) {
175 properties = new ConcurrentHashMap<String, Object>();
176 }
177 return properties;
178 }
179
180 public void setProperties(Map<String, Object> properties) {
181 this.properties = properties;
182 }
183
184 public Message getIn() {
185 if (in == null) {
186 in = createInMessage();
187 configureMessage(in);
188 }
189 return in;
190 }
191
192 public void setIn(Message in) {
193 this.in = in;
194 configureMessage(in);
195 }
196
197 public Message getOut() {
198 if (out == null) {
199 out = createOutMessage();
200 configureMessage(out);
201 }
202 return out;
203 }
204
205 public boolean hasOut() {
206 return out != null;
207 }
208
209 public Message getOut(boolean lazyCreate) {
210 if (out == null && lazyCreate) {
211 out = createOutMessage();
212 configureMessage(out);
213 }
214 return out;
215 }
216
217 public void setOut(Message out) {
218 this.out = out;
219 configureMessage(out);
220 }
221
222 public Exception getException() {
223 return exception;
224 }
225
226 public <T> T getException(Class<T> type) {
227 if (exception == null) {
228 return null;
229 }
230
231 Iterator<Throwable> it = ObjectHelper.createExceptionIterator(exception);
232 while (it.hasNext()) {
233 Throwable e = it.next();
234 if (type.isInstance(e)) {
235 return type.cast(e);
236 }
237 }
238 // not found
239 return null;
240 }
241
242 public void setException(Exception exception) {
243 this.exception = exception;
244 }
245
246 public ExchangePattern getPattern() {
247 return pattern;
248 }
249
250 public void setPattern(ExchangePattern pattern) {
251 this.pattern = pattern;
252 }
253
254 public Endpoint getFromEndpoint() {
255 return fromEndpoint;
256 }
257
258 public void setFromEndpoint(Endpoint fromEndpoint) {
259 this.fromEndpoint = fromEndpoint;
260 }
261
262 public Message getFault() {
263 if (fault == null) {
264 fault = createFaultMessage();
265 configureMessage(fault);
266 }
267 return fault;
268 }
269
270 public boolean hasFault() {
271 return fault != null;
272 }
273
274 public Message getFault(boolean lazyCreate) {
275 if (fault == null && lazyCreate) {
276 fault = createFaultMessage();
277 configureMessage(fault);
278 }
279 return fault;
280 }
281
282 public void setFault(Message fault) {
283 this.fault = fault;
284 configureMessage(fault);
285 }
286
287 public void removeFault() {
288 this.fault = null;
289 }
290
291 public String getExchangeId() {
292 if (exchangeId == null) {
293 exchangeId = createExchangeId();
294 }
295 return exchangeId;
296 }
297
298 public void setExchangeId(String id) {
299 this.exchangeId = id;
300 }
301
302 public boolean isFailed() {
303 if (hasFault()) {
304 Object faultBody = getFault().getBody();
305 if (faultBody != null) {
306 return true;
307 }
308 }
309 return getException() != null;
310 }
311
312 public boolean isTransacted() {
313 Boolean transacted = getProperty(TRANSACTED, Boolean.class);
314 return transacted != null && transacted;
315 }
316
317 public boolean isRollbackOnly() {
318 Boolean rollback = getProperty(ROLLBACK_ONLY, Boolean.class);
319 return rollback != null && rollback;
320 }
321
322 public UnitOfWork getUnitOfWork() {
323 return unitOfWork;
324 }
325
326 public void setUnitOfWork(UnitOfWork unitOfWork) {
327 this.unitOfWork = unitOfWork;
328 if (this.onCompletions != null) {
329 // now an unit of work has been assigned so add the on completions
330 // we might have registered already
331 for (Synchronization onCompletion : this.onCompletions) {
332 this.unitOfWork.addSynchronization(onCompletion);
333 }
334 // cleanup the temporary on completion list as they now have been registered
335 // on the unit of work
336 this.onCompletions.clear();
337 this.onCompletions = null;
338 }
339 }
340
341 public void addOnCompletion(Synchronization onCompletion) {
342 if (this.unitOfWork == null) {
343 // unit of work not yet registered so we store the on completion temporary
344 // until the unit of work is assigned to this exchange by the UnitOfWorkProcessor
345 if (this.onCompletions == null) {
346 this.onCompletions = new ArrayList<Synchronization>();
347 }
348 this.onCompletions.add(onCompletion);
349 } else {
350 this.getUnitOfWork().addSynchronization(onCompletion);
351 }
352 }
353
354 /**
355 * Factory method used to lazily create the IN message
356 */
357 protected Message createInMessage() {
358 return new DefaultMessage();
359 }
360
361 /**
362 * Factory method to lazily create the OUT message
363 */
364 protected Message createOutMessage() {
365 return new DefaultMessage();
366 }
367
368 /**
369 * Factory method to lazily create the FAULT message
370 */
371 protected Message createFaultMessage() {
372 return new DefaultMessage();
373 }
374
375 /**
376 * Configures the message after it has been set on the exchange
377 */
378 protected void configureMessage(Message message) {
379 if (message instanceof MessageSupport) {
380 MessageSupport messageSupport = (MessageSupport)message;
381 messageSupport.setExchange(this);
382 }
383 }
384
385 protected String createExchangeId() {
386 String answer = null;
387 if (in != null) {
388 answer = in.createExchangeId();
389 }
390 if (answer == null) {
391 answer = DefaultExchange.DEFAULT_ID_GENERATOR.generateId();
392 }
393 return answer;
394 }
395
396 }