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 */ 017package org.apache.camel.util; 018 019import java.util.ArrayList; 020import java.util.HashMap; 021import java.util.List; 022import java.util.Map; 023import java.util.concurrent.ConcurrentHashMap; 024import java.util.concurrent.ExecutionException; 025import java.util.concurrent.Future; 026import java.util.concurrent.TimeUnit; 027import java.util.concurrent.TimeoutException; 028 029import org.apache.camel.CamelContext; 030import org.apache.camel.CamelExchangeException; 031import org.apache.camel.CamelExecutionException; 032import org.apache.camel.Endpoint; 033import org.apache.camel.Exchange; 034import org.apache.camel.ExchangePattern; 035import org.apache.camel.InvalidPayloadException; 036import org.apache.camel.Message; 037import org.apache.camel.MessageHistory; 038import org.apache.camel.NoSuchBeanException; 039import org.apache.camel.NoSuchEndpointException; 040import org.apache.camel.NoSuchHeaderException; 041import org.apache.camel.NoSuchPropertyException; 042import org.apache.camel.NoTypeConversionAvailableException; 043import org.apache.camel.TypeConversionException; 044import org.apache.camel.TypeConverter; 045import org.apache.camel.impl.DefaultExchange; 046import org.apache.camel.impl.MessageSupport; 047import org.apache.camel.spi.UnitOfWork; 048 049/** 050 * Some helper methods for working with {@link Exchange} objects 051 * 052 * @version 053 */ 054public final class ExchangeHelper { 055 056 /** 057 * Utility classes should not have a public constructor. 058 */ 059 private ExchangeHelper() { 060 } 061 062 /** 063 * Extracts the Exchange.BINDING of the given type or null if not present 064 * 065 * @param exchange the message exchange 066 * @param type the expected binding type 067 * @return the binding object of the given type or null if it could not be found or converted 068 */ 069 public static <T> T getBinding(Exchange exchange, Class<T> type) { 070 return exchange != null ? exchange.getProperty(Exchange.BINDING, type) : null; 071 } 072 073 /** 074 * Attempts to resolve the endpoint for the given value 075 * 076 * @param exchange the message exchange being processed 077 * @param value the value which can be an {@link Endpoint} or an object 078 * which provides a String representation of an endpoint via 079 * {@link #toString()} 080 * @return the endpoint 081 * @throws NoSuchEndpointException if the endpoint cannot be resolved 082 */ 083 public static Endpoint resolveEndpoint(Exchange exchange, Object value) throws NoSuchEndpointException { 084 Endpoint endpoint; 085 if (value instanceof Endpoint) { 086 endpoint = (Endpoint) value; 087 } else { 088 String uri = value.toString().trim(); 089 endpoint = CamelContextHelper.getMandatoryEndpoint(exchange.getContext(), uri); 090 } 091 return endpoint; 092 } 093 094 /** 095 * Gets the mandatory property of the exchange of the correct type 096 * 097 * @param exchange the exchange 098 * @param propertyName the property name 099 * @param type the type 100 * @return the property value 101 * @throws TypeConversionException is thrown if error during type conversion 102 * @throws NoSuchPropertyException is thrown if no property exists 103 */ 104 public static <T> T getMandatoryProperty(Exchange exchange, String propertyName, Class<T> type) throws NoSuchPropertyException { 105 T result = exchange.getProperty(propertyName, type); 106 if (result != null) { 107 return result; 108 } 109 throw new NoSuchPropertyException(exchange, propertyName, type); 110 } 111 112 /** 113 * Gets the mandatory inbound header of the correct type 114 * 115 * @param exchange the exchange 116 * @param headerName the header name 117 * @param type the type 118 * @return the header value 119 * @throws TypeConversionException is thrown if error during type conversion 120 * @throws NoSuchHeaderException is thrown if no headers exists 121 */ 122 public static <T> T getMandatoryHeader(Exchange exchange, String headerName, Class<T> type) throws TypeConversionException, NoSuchHeaderException { 123 T answer = exchange.getIn().getHeader(headerName, type); 124 if (answer == null) { 125 throw new NoSuchHeaderException(exchange, headerName, type); 126 } 127 return answer; 128 } 129 130 /** 131 * Returns the mandatory inbound message body of the correct type or throws 132 * an exception if it is not present 133 * 134 * @param exchange the exchange 135 * @return the body, is never <tt>null</tt> 136 * @throws InvalidPayloadException Is thrown if the body being <tt>null</tt> or wrong class type 137 * @deprecated use {@link org.apache.camel.Message#getMandatoryBody()} 138 */ 139 @Deprecated 140 public static Object getMandatoryInBody(Exchange exchange) throws InvalidPayloadException { 141 return exchange.getIn().getMandatoryBody(); 142 } 143 144 /** 145 * Returns the mandatory inbound message body of the correct type or throws 146 * an exception if it is not present 147 * @deprecated use {@link org.apache.camel.Message#getMandatoryBody(Class)} 148 */ 149 @Deprecated 150 public static <T> T getMandatoryInBody(Exchange exchange, Class<T> type) throws InvalidPayloadException { 151 return exchange.getIn().getMandatoryBody(type); 152 } 153 154 /** 155 * Returns the mandatory outbound message body of the correct type or throws 156 * an exception if it is not present 157 * @deprecated use {@link org.apache.camel.Message#getMandatoryBody()} 158 */ 159 @Deprecated 160 public static Object getMandatoryOutBody(Exchange exchange) throws InvalidPayloadException { 161 return exchange.getOut().getMandatoryBody(); 162 } 163 164 /** 165 * Returns the mandatory outbound message body of the correct type or throws 166 * an exception if it is not present 167 * @deprecated use {@link org.apache.camel.Message#getMandatoryBody(Class)} 168 */ 169 @Deprecated 170 public static <T> T getMandatoryOutBody(Exchange exchange, Class<T> type) throws InvalidPayloadException { 171 return exchange.getOut().getMandatoryBody(type); 172 } 173 174 /** 175 * Converts the value to the given expected type or throws an exception 176 * 177 * @return the converted value 178 * @throws TypeConversionException is thrown if error during type conversion 179 * @throws NoTypeConversionAvailableException} if no type converters exists to convert to the given type 180 */ 181 public static <T> T convertToMandatoryType(Exchange exchange, Class<T> type, Object value) 182 throws TypeConversionException, NoTypeConversionAvailableException { 183 CamelContext camelContext = exchange.getContext(); 184 ObjectHelper.notNull(camelContext, "CamelContext of Exchange"); 185 TypeConverter converter = camelContext.getTypeConverter(); 186 if (converter != null) { 187 return converter.mandatoryConvertTo(type, exchange, value); 188 } 189 throw new NoTypeConversionAvailableException(value, type); 190 } 191 192 /** 193 * Converts the value to the given expected type 194 * 195 * @return the converted value 196 * @throws org.apache.camel.TypeConversionException is thrown if error during type conversion 197 */ 198 public static <T> T convertToType(Exchange exchange, Class<T> type, Object value) throws TypeConversionException { 199 CamelContext camelContext = exchange.getContext(); 200 ObjectHelper.notNull(camelContext, "CamelContext of Exchange"); 201 TypeConverter converter = camelContext.getTypeConverter(); 202 if (converter != null) { 203 return converter.convertTo(type, exchange, value); 204 } 205 return null; 206 } 207 208 /** 209 * Creates a new instance and copies from the current message exchange so that it can be 210 * forwarded to another destination as a new instance. Unlike regular copy this operation 211 * will not share the same {@link org.apache.camel.spi.UnitOfWork} so its should be used 212 * for async messaging, where the original and copied exchange are independent. 213 * 214 * @param exchange original copy of the exchange 215 * @param handover whether the on completion callbacks should be handed over to the new copy. 216 */ 217 public static Exchange createCorrelatedCopy(Exchange exchange, boolean handover) { 218 return createCorrelatedCopy(exchange, handover, false); 219 } 220 221 /** 222 * Creates a new instance and copies from the current message exchange so that it can be 223 * forwarded to another destination as a new instance. Unlike regular copy this operation 224 * will not share the same {@link org.apache.camel.spi.UnitOfWork} so its should be used 225 * for async messaging, where the original and copied exchange are independent. 226 * 227 * @param exchange original copy of the exchange 228 * @param handover whether the on completion callbacks should be handed over to the new copy. 229 * @param useSameMessageId whether to use same message id on the copy message. 230 */ 231 public static Exchange createCorrelatedCopy(Exchange exchange, boolean handover, boolean useSameMessageId) { 232 String id = exchange.getExchangeId(); 233 234 Exchange copy = exchange.copy(); 235 // do not reuse message id on copy 236 if (!useSameMessageId) { 237 if (copy.hasOut()) { 238 copy.getOut().setMessageId(null); 239 } 240 copy.getIn().setMessageId(null); 241 } 242 // do not share the unit of work 243 copy.setUnitOfWork(null); 244 // do not reuse the message id 245 // hand over on completion to the copy if we got any 246 UnitOfWork uow = exchange.getUnitOfWork(); 247 if (handover && uow != null) { 248 uow.handoverSynchronization(copy); 249 } 250 // set a correlation id so we can track back the original exchange 251 copy.setProperty(Exchange.CORRELATION_ID, id); 252 return copy; 253 } 254 255 /** 256 * Creates a new instance and copies from the current message exchange so that it can be 257 * forwarded to another destination as a new instance. 258 * 259 * @param exchange original copy of the exchange 260 * @param preserveExchangeId whether or not the exchange id should be preserved 261 * @return the copy 262 */ 263 public static Exchange createCopy(Exchange exchange, boolean preserveExchangeId) { 264 Exchange copy = exchange.copy(); 265 if (preserveExchangeId) { 266 // must preserve exchange id 267 copy.setExchangeId(exchange.getExchangeId()); 268 } 269 return copy; 270 } 271 272 /** 273 * Copies the results of a message exchange from the source exchange to the result exchange 274 * which will copy the message contents, exchange properties and the exception. 275 * Notice the {@link ExchangePattern} is <b>not</b> copied/altered. 276 * 277 * @param result the result exchange which will have the output and error state added 278 * @param source the source exchange which is not modified 279 */ 280 public static void copyResults(Exchange result, Exchange source) { 281 282 // -------------------------------------------------------------------- 283 // TODO: merge logic with that of copyResultsPreservePattern() 284 // -------------------------------------------------------------------- 285 286 if (result == source) { 287 // we just need to ensure MEP is as expected (eg copy result to OUT if out capable) 288 // and the result is not failed 289 if (result.getPattern() == ExchangePattern.InOptionalOut) { 290 // keep as is 291 } else if (result.getPattern().isOutCapable() && !result.hasOut() && !result.isFailed()) { 292 // copy IN to OUT as we expect a OUT response 293 result.getOut().copyFrom(source.getIn()); 294 } 295 return; 296 } 297 298 if (result != source) { 299 result.setException(source.getException()); 300 if (source.hasOut()) { 301 result.getOut().copyFrom(source.getOut()); 302 } else if (result.getPattern() == ExchangePattern.InOptionalOut) { 303 // special case where the result is InOptionalOut and with no OUT response 304 // so we should return null to indicate this fact 305 result.setOut(null); 306 } else { 307 // no results so lets copy the last input 308 // as the final processor on a pipeline might not 309 // have created any OUT; such as a mock:endpoint 310 // so lets assume the last IN is the OUT 311 if (result.getPattern().isOutCapable()) { 312 // only set OUT if its OUT capable 313 result.getOut().copyFrom(source.getIn()); 314 } else { 315 // if not replace IN instead to keep the MEP 316 result.getIn().copyFrom(source.getIn()); 317 // clear any existing OUT as the result is on the IN 318 if (result.hasOut()) { 319 result.setOut(null); 320 } 321 } 322 } 323 324 if (source.hasProperties()) { 325 result.getProperties().putAll(source.getProperties()); 326 } 327 } 328 } 329 330 /** 331 * Copies the <code>source</code> exchange to <code>target</code> exchange 332 * preserving the {@link ExchangePattern} of <code>target</code>. 333 * 334 * @param source source exchange. 335 * @param result target exchange. 336 */ 337 public static void copyResultsPreservePattern(Exchange result, Exchange source) { 338 339 // -------------------------------------------------------------------- 340 // TODO: merge logic with that of copyResults() 341 // -------------------------------------------------------------------- 342 343 if (result == source) { 344 // we just need to ensure MEP is as expected (eg copy result to OUT if out capable) 345 // and the result is not failed 346 if (result.getPattern() == ExchangePattern.InOptionalOut) { 347 // keep as is 348 } else if (result.getPattern().isOutCapable() && !result.hasOut() && !result.isFailed()) { 349 // copy IN to OUT as we expect a OUT response 350 result.getOut().copyFrom(source.getIn()); 351 } 352 return; 353 } 354 355 // copy in message 356 result.getIn().copyFrom(source.getIn()); 357 358 // copy out message 359 if (source.hasOut()) { 360 // exchange pattern sensitive 361 Message resultMessage = source.getOut().isFault() ? result.getOut() : getResultMessage(result); 362 resultMessage.copyFrom(source.getOut()); 363 } 364 365 // copy exception 366 result.setException(source.getException()); 367 368 // copy properties 369 if (source.hasProperties()) { 370 result.getProperties().putAll(source.getProperties()); 371 } 372 } 373 374 /** 375 * Returns the message where to write results in an 376 * exchange-pattern-sensitive way. 377 * 378 * @param exchange message exchange. 379 * @return result message. 380 */ 381 public static Message getResultMessage(Exchange exchange) { 382 if (exchange.getPattern().isOutCapable()) { 383 return exchange.getOut(); 384 } else { 385 return exchange.getIn(); 386 } 387 } 388 389 /** 390 * Returns true if the given exchange pattern (if defined) can support OUT messages 391 * 392 * @param exchange the exchange to interrogate 393 * @return true if the exchange is defined as an {@link ExchangePattern} which supports 394 * OUT messages 395 */ 396 public static boolean isOutCapable(Exchange exchange) { 397 ExchangePattern pattern = exchange.getPattern(); 398 return pattern != null && pattern.isOutCapable(); 399 } 400 401 /** 402 * Creates a new instance of the given type from the injector 403 * 404 * @param exchange the exchange 405 * @param type the given type 406 * @return the created instance of the given type 407 */ 408 public static <T> T newInstance(Exchange exchange, Class<T> type) { 409 return exchange.getContext().getInjector().newInstance(type); 410 } 411 412 /** 413 * Creates a Map of the variables which are made available to a script or template 414 * 415 * @param exchange the exchange to make available 416 * @return a Map populated with the require variables 417 */ 418 public static Map<String, Object> createVariableMap(Exchange exchange) { 419 Map<String, Object> answer = new HashMap<String, Object>(); 420 populateVariableMap(exchange, answer); 421 return answer; 422 } 423 424 /** 425 * Populates the Map with the variables which are made available to a script or template 426 * 427 * @param exchange the exchange to make available 428 * @param map the map to populate 429 */ 430 public static void populateVariableMap(Exchange exchange, Map<String, Object> map) { 431 map.put("exchange", exchange); 432 Message in = exchange.getIn(); 433 map.put("in", in); 434 map.put("request", in); 435 map.put("headers", in.getHeaders()); 436 map.put("body", in.getBody()); 437 if (isOutCapable(exchange)) { 438 // if we are out capable then set out and response as well 439 // however only grab OUT if it exists, otherwise reuse IN 440 // this prevents side effects to alter the Exchange if we force creating an OUT message 441 Message msg = exchange.hasOut() ? exchange.getOut() : exchange.getIn(); 442 map.put("out", msg); 443 map.put("response", msg); 444 } 445 map.put("camelContext", exchange.getContext()); 446 } 447 448 /** 449 * Returns the MIME content type on the input message or null if one is not defined 450 * 451 * @param exchange the exchange 452 * @return the MIME content type 453 */ 454 public static String getContentType(Exchange exchange) { 455 return MessageHelper.getContentType(exchange.getIn()); 456 } 457 458 /** 459 * Returns the MIME content encoding on the input message or null if one is not defined 460 * 461 * @param exchange the exchange 462 * @return the MIME content encoding 463 */ 464 public static String getContentEncoding(Exchange exchange) { 465 return MessageHelper.getContentEncoding(exchange.getIn()); 466 } 467 468 /** 469 * Performs a lookup in the registry of the mandatory bean name and throws an exception if it could not be found 470 * 471 * @param exchange the exchange 472 * @param name the bean name 473 * @return the bean 474 * @throws NoSuchBeanException if no bean could be found in the registry 475 */ 476 public static Object lookupMandatoryBean(Exchange exchange, String name) throws NoSuchBeanException { 477 Object value = lookupBean(exchange, name); 478 if (value == null) { 479 throw new NoSuchBeanException(name); 480 } 481 return value; 482 } 483 484 /** 485 * Performs a lookup in the registry of the mandatory bean name and throws an exception if it could not be found 486 * 487 * @param exchange the exchange 488 * @param name the bean name 489 * @param type the expected bean type 490 * @return the bean 491 * @throws NoSuchBeanException if no bean could be found in the registry 492 */ 493 public static <T> T lookupMandatoryBean(Exchange exchange, String name, Class<T> type) { 494 T value = lookupBean(exchange, name, type); 495 if (value == null) { 496 throw new NoSuchBeanException(name); 497 } 498 return value; 499 } 500 501 /** 502 * Performs a lookup in the registry of the bean name 503 * 504 * @param exchange the exchange 505 * @param name the bean name 506 * @return the bean, or <tt>null</tt> if no bean could be found 507 */ 508 public static Object lookupBean(Exchange exchange, String name) { 509 return exchange.getContext().getRegistry().lookupByName(name); 510 } 511 512 /** 513 * Performs a lookup in the registry of the bean name and type 514 * 515 * @param exchange the exchange 516 * @param name the bean name 517 * @param type the expected bean type 518 * @return the bean, or <tt>null</tt> if no bean could be found 519 */ 520 public static <T> T lookupBean(Exchange exchange, String name, Class<T> type) { 521 return exchange.getContext().getRegistry().lookupByNameAndType(name, type); 522 } 523 524 /** 525 * Returns the first exchange in the given collection of exchanges which has the same exchange ID as the one given 526 * or null if none could be found 527 * 528 * @param exchanges the exchanges 529 * @param exchangeId the exchangeId to find 530 * @return matching exchange, or <tt>null</tt> if none found 531 */ 532 public static Exchange getExchangeById(Iterable<Exchange> exchanges, String exchangeId) { 533 for (Exchange exchange : exchanges) { 534 String id = exchange.getExchangeId(); 535 if (id != null && id.equals(exchangeId)) { 536 return exchange; 537 } 538 } 539 return null; 540 } 541 542 /** 543 * Prepares the exchanges for aggregation. 544 * <p/> 545 * This implementation will copy the OUT body to the IN body so when you do 546 * aggregation the body is <b>only</b> in the IN body to avoid confusing end users. 547 * 548 * @param oldExchange the old exchange 549 * @param newExchange the new exchange 550 */ 551 public static void prepareAggregation(Exchange oldExchange, Exchange newExchange) { 552 // move body/header from OUT to IN 553 if (oldExchange != null) { 554 if (oldExchange.hasOut()) { 555 oldExchange.setIn(oldExchange.getOut()); 556 oldExchange.setOut(null); 557 } 558 } 559 560 if (newExchange != null) { 561 if (newExchange.hasOut()) { 562 newExchange.setIn(newExchange.getOut()); 563 newExchange.setOut(null); 564 } 565 } 566 } 567 568 /** 569 * Checks whether the exchange has been failure handed 570 * 571 * @param exchange the exchange 572 * @return <tt>true</tt> if failure handled, <tt>false</tt> otherwise 573 */ 574 public static boolean isFailureHandled(Exchange exchange) { 575 return exchange.getProperty(Exchange.FAILURE_HANDLED, false, Boolean.class); 576 } 577 578 /** 579 * Checks whether the exchange {@link UnitOfWork} is exhausted 580 * 581 * @param exchange the exchange 582 * @return <tt>true</tt> if exhausted, <tt>false</tt> otherwise 583 */ 584 public static boolean isUnitOfWorkExhausted(Exchange exchange) { 585 return exchange.getProperty(Exchange.UNIT_OF_WORK_EXHAUSTED, false, Boolean.class); 586 } 587 588 /** 589 * Sets the exchange to be failure handled. 590 * 591 * @param exchange the exchange 592 */ 593 public static void setFailureHandled(Exchange exchange) { 594 exchange.setProperty(Exchange.FAILURE_HANDLED, Boolean.TRUE); 595 // clear exception since its failure handled 596 exchange.setException(null); 597 } 598 599 /** 600 * Checks whether the exchange is redelivery exhausted 601 * 602 * @param exchange the exchange 603 * @return <tt>true</tt> if exhausted, <tt>false</tt> otherwise 604 */ 605 public static boolean isRedeliveryExhausted(Exchange exchange) { 606 return exchange.getProperty(Exchange.REDELIVERY_EXHAUSTED, false, Boolean.class); 607 } 608 609 /** 610 * Checks whether the exchange {@link UnitOfWork} is redelivered 611 * 612 * @param exchange the exchange 613 * @return <tt>true</tt> if redelivered, <tt>false</tt> otherwise 614 */ 615 public static boolean isRedelivered(Exchange exchange) { 616 return exchange.getIn().hasHeaders() && exchange.getIn().getHeader(Exchange.REDELIVERED, false, Boolean.class); 617 } 618 619 /** 620 * Checks whether the exchange {@link UnitOfWork} has been interrupted during processing 621 * 622 * @param exchange the exchange 623 * @return <tt>true</tt> if interrupted, <tt>false</tt> otherwise 624 */ 625 public static boolean isInterrupted(Exchange exchange) { 626 return exchange.getException(InterruptedException.class) != null; 627 } 628 629 /** 630 * Extracts the body from the given exchange. 631 * <p/> 632 * If the exchange pattern is provided it will try to honor it and retrieve the body 633 * from either IN or OUT according to the pattern. 634 * 635 * @param exchange the exchange 636 * @param pattern exchange pattern if given, can be <tt>null</tt> 637 * @return the result body, can be <tt>null</tt>. 638 * @throws CamelExecutionException is thrown if the processing of the exchange failed 639 */ 640 public static Object extractResultBody(Exchange exchange, ExchangePattern pattern) { 641 Object answer = null; 642 if (exchange != null) { 643 // rethrow if there was an exception during execution 644 if (exchange.getException() != null) { 645 throw ObjectHelper.wrapCamelExecutionException(exchange, exchange.getException()); 646 } 647 648 // result could have a fault message 649 if (hasFaultMessage(exchange)) { 650 Message msg = exchange.hasOut() ? exchange.getOut() : exchange.getIn(); 651 answer = msg.getBody(); 652 return answer; 653 } 654 655 // okay no fault then return the response according to the pattern 656 // try to honor pattern if provided 657 boolean notOut = pattern != null && !pattern.isOutCapable(); 658 boolean hasOut = exchange.hasOut(); 659 if (hasOut && !notOut) { 660 // we have a response in out and the pattern is out capable 661 answer = exchange.getOut().getBody(); 662 } else if (!hasOut && exchange.getPattern() == ExchangePattern.InOptionalOut) { 663 // special case where the result is InOptionalOut and with no OUT response 664 // so we should return null to indicate this fact 665 answer = null; 666 } else { 667 // use IN as the response 668 answer = exchange.getIn().getBody(); 669 } 670 } 671 return answer; 672 } 673 674 /** 675 * Tests whether the exchange has a fault message set and that its not null. 676 * 677 * @param exchange the exchange 678 * @return <tt>true</tt> if fault message exists 679 */ 680 public static boolean hasFaultMessage(Exchange exchange) { 681 Message msg = exchange.hasOut() ? exchange.getOut() : exchange.getIn(); 682 return msg.isFault() && msg.getBody() != null; 683 } 684 685 /** 686 * Tests whether the exchange has already been handled by the error handler 687 * 688 * @param exchange the exchange 689 * @return <tt>true</tt> if handled already by error handler, <tt>false</tt> otherwise 690 */ 691 public static boolean hasExceptionBeenHandledByErrorHandler(Exchange exchange) { 692 return Boolean.TRUE.equals(exchange.getProperty(Exchange.ERRORHANDLER_HANDLED)); 693 } 694 695 /** 696 * Extracts the body from the given future, that represents a handle to an asynchronous exchange. 697 * <p/> 698 * Will wait until the future task is complete. 699 * 700 * @param context the camel context 701 * @param future the future handle 702 * @param type the expected body response type 703 * @return the result body, can be <tt>null</tt>. 704 * @throws CamelExecutionException is thrown if the processing of the exchange failed 705 */ 706 public static <T> T extractFutureBody(CamelContext context, Future<Object> future, Class<T> type) { 707 try { 708 return doExtractFutureBody(context, future.get(), type); 709 } catch (InterruptedException e) { 710 throw ObjectHelper.wrapRuntimeCamelException(e); 711 } catch (ExecutionException e) { 712 // execution failed due to an exception so rethrow the cause 713 throw ObjectHelper.wrapCamelExecutionException(null, e.getCause()); 714 } finally { 715 // its harmless to cancel if task is already completed 716 // and in any case we do not want to get hold of the task a 2nd time 717 // and its recommended to cancel according to Brian Goetz in his Java Concurrency in Practice book 718 future.cancel(true); 719 } 720 } 721 722 /** 723 * Extracts the body from the given future, that represents a handle to an asynchronous exchange. 724 * <p/> 725 * Will wait for the future task to complete, but waiting at most the timeout value. 726 * 727 * @param context the camel context 728 * @param future the future handle 729 * @param timeout timeout value 730 * @param unit timeout unit 731 * @param type the expected body response type 732 * @return the result body, can be <tt>null</tt>. 733 * @throws CamelExecutionException is thrown if the processing of the exchange failed 734 * @throws java.util.concurrent.TimeoutException is thrown if a timeout triggered 735 */ 736 public static <T> T extractFutureBody(CamelContext context, Future<Object> future, long timeout, TimeUnit unit, Class<T> type) throws TimeoutException { 737 try { 738 if (timeout > 0) { 739 return doExtractFutureBody(context, future.get(timeout, unit), type); 740 } else { 741 return doExtractFutureBody(context, future.get(), type); 742 } 743 } catch (InterruptedException e) { 744 // execution failed due interruption so rethrow the cause 745 throw ObjectHelper.wrapCamelExecutionException(null, e); 746 } catch (ExecutionException e) { 747 // execution failed due to an exception so rethrow the cause 748 throw ObjectHelper.wrapCamelExecutionException(null, e.getCause()); 749 } finally { 750 // its harmless to cancel if task is already completed 751 // and in any case we do not want to get hold of the task a 2nd time 752 // and its recommended to cancel according to Brian Goetz in his Java Concurrency in Practice book 753 future.cancel(true); 754 } 755 } 756 757 private static <T> T doExtractFutureBody(CamelContext context, Object result, Class<T> type) { 758 if (result == null) { 759 return null; 760 } 761 if (type.isAssignableFrom(result.getClass())) { 762 return type.cast(result); 763 } 764 if (result instanceof Exchange) { 765 Exchange exchange = (Exchange) result; 766 Object answer = ExchangeHelper.extractResultBody(exchange, exchange.getPattern()); 767 return context.getTypeConverter().convertTo(type, exchange, answer); 768 } 769 return context.getTypeConverter().convertTo(type, result); 770 } 771 772 /** 773 * @deprecated use org.apache.camel.CamelExchangeException.createExceptionMessage instead 774 */ 775 @Deprecated 776 public static String createExceptionMessage(String message, Exchange exchange, Throwable cause) { 777 return CamelExchangeException.createExceptionMessage(message, exchange, cause); 778 } 779 780 /** 781 * Strategy to prepare results before next iterator or when we are complete, 782 * which is done by copying OUT to IN, so there is only an IN as input 783 * for the next iteration. 784 * 785 * @param exchange the exchange to prepare 786 */ 787 public static void prepareOutToIn(Exchange exchange) { 788 // we are routing using pipes and filters so we need to manually copy OUT to IN 789 if (exchange.hasOut()) { 790 exchange.getIn().copyFrom(exchange.getOut()); 791 exchange.setOut(null); 792 } 793 } 794 795 /** 796 * Gets both the messageId and exchangeId to be used for logging purposes. 797 * <p/> 798 * Logging both ids, can help to correlate exchanges which may be redelivered messages 799 * from for example a JMS broker. 800 * 801 * @param exchange the exchange 802 * @return a log message with both the messageId and exchangeId 803 */ 804 public static String logIds(Exchange exchange) { 805 String msgId = exchange.hasOut() ? exchange.getOut().getMessageId() : exchange.getIn().getMessageId(); 806 return "(MessageId: " + msgId + " on ExchangeId: " + exchange.getExchangeId() + ")"; 807 } 808 809 /** 810 * Copies the exchange but the copy will be tied to the given context 811 * 812 * @param exchange the source exchange 813 * @param context the camel context 814 * @return a copy with the given camel context 815 */ 816 public static Exchange copyExchangeAndSetCamelContext(Exchange exchange, CamelContext context) { 817 return copyExchangeAndSetCamelContext(exchange, context, true); 818 } 819 820 /** 821 * Copies the exchange but the copy will be tied to the given context 822 * 823 * @param exchange the source exchange 824 * @param context the camel context 825 * @param handover whether to handover on completions from the source to the copy 826 * @return a copy with the given camel context 827 */ 828 public static Exchange copyExchangeAndSetCamelContext(Exchange exchange, CamelContext context, boolean handover) { 829 DefaultExchange answer = new DefaultExchange(context, exchange.getPattern()); 830 if (exchange.hasProperties()) { 831 answer.setProperties(safeCopy(exchange.getProperties())); 832 } 833 if (handover) { 834 // Need to hand over the completion for async invocation 835 exchange.handoverCompletions(answer); 836 } 837 answer.setIn(exchange.getIn().copy()); 838 if (exchange.hasOut()) { 839 answer.setOut(exchange.getOut().copy()); 840 } 841 answer.setException(exchange.getException()); 842 return answer; 843 } 844 845 /** 846 * Replaces the existing message with the new message 847 * 848 * @param exchange the exchange 849 * @param newMessage the new message 850 * @param outOnly whether to replace the message as OUT message 851 */ 852 public static void replaceMessage(Exchange exchange, Message newMessage, boolean outOnly) { 853 Message old = exchange.hasOut() ? exchange.getOut() : exchange.getIn(); 854 if (outOnly || exchange.hasOut()) { 855 exchange.setOut(newMessage); 856 } else { 857 exchange.setIn(newMessage); 858 } 859 860 // need to de-reference old from the exchange so it can be GC 861 if (old instanceof MessageSupport) { 862 ((MessageSupport) old).setExchange(null); 863 } 864 } 865 866 @SuppressWarnings("unchecked") 867 private static Map<String, Object> safeCopy(Map<String, Object> properties) { 868 if (properties == null) { 869 return null; 870 } 871 872 Map<String, Object> answer = new ConcurrentHashMap<String, Object>(properties); 873 874 // safe copy message history using a defensive copy 875 List<MessageHistory> history = (List<MessageHistory>) answer.remove(Exchange.MESSAGE_HISTORY); 876 if (history != null) { 877 answer.put(Exchange.MESSAGE_HISTORY, new ArrayList<MessageHistory>(history)); 878 } 879 880 return answer; 881 } 882}