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.builder;
018
019 import org.apache.camel.Endpoint;
020 import org.apache.camel.LoggingLevel;
021 import org.apache.camel.NoSuchEndpointException;
022 import org.apache.camel.Predicate;
023 import org.apache.camel.Processor;
024 import org.apache.camel.processor.DeadLetterChannel;
025 import org.apache.camel.processor.Logger;
026 import org.apache.camel.processor.RedeliveryPolicy;
027 import org.apache.camel.processor.SendProcessor;
028 import org.apache.camel.spi.RouteContext;
029 import org.apache.camel.util.ObjectHelper;
030 import org.apache.commons.logging.LogFactory;
031
032 /**
033 * A builder of a <a
034 * href="http://camel.apache.org/dead-letter-channel.html">Dead Letter
035 * Channel</a>
036 *
037 * @version $Revision: 882139 $
038 */
039 public class DeadLetterChannelBuilder extends DefaultErrorHandlerBuilder {
040
041 public DeadLetterChannelBuilder() {
042 // no-arg constructor used by Spring DSL
043 }
044
045 public DeadLetterChannelBuilder(Endpoint deadLetter) {
046 setDeadLetter(deadLetter);
047 }
048
049 public DeadLetterChannelBuilder(String uri) {
050 setDeadLetterUri(uri);
051 }
052
053 public Processor createErrorHandler(RouteContext routeContext, Processor processor) throws Exception {
054 validateDeadLetterUri(routeContext);
055
056 DeadLetterChannel answer = new DeadLetterChannel(processor, getLogger(), getOnRedelivery(), getRedeliveryPolicy(),
057 getHandledPolicy(), getExceptionPolicyStrategy(), getFailureProcessor(), getDeadLetterUri(),
058 isUseOriginalMessage());
059 // configure error handler before we can use it
060 configure(answer);
061 return answer;
062 }
063
064 public boolean supportTransacted() {
065 return false;
066 }
067
068 // Properties
069 // -------------------------------------------------------------------------
070
071 public Processor getFailureProcessor() {
072 if (failureProcessor == null) {
073 failureProcessor = new SendProcessor(deadLetter);
074 }
075 return failureProcessor;
076 }
077
078 protected void validateDeadLetterUri(RouteContext routeContext) {
079 if (deadLetter == null) {
080 ObjectHelper.notEmpty(deadLetterUri, "deadLetterUri", this);
081 deadLetter = routeContext.getCamelContext().getEndpoint(deadLetterUri);
082 if (deadLetter == null) {
083 throw new NoSuchEndpointException(deadLetterUri);
084 }
085 }
086 }
087
088 protected Predicate createHandledPolicy() {
089 // should be handled by default for dead letter channel
090 return PredicateBuilder.toPredicate(ExpressionBuilder.constantExpression(true));
091 }
092
093 @Override
094 protected RedeliveryPolicy createRedeliveryPolicy() {
095 return new RedeliveryPolicy();
096 }
097
098 protected Logger createLogger() {
099 return new Logger(LogFactory.getLog(DeadLetterChannel.class), LoggingLevel.ERROR);
100 }
101
102 @Override
103 public String toString() {
104 return "DeadLetterChannelBuilder(" + deadLetterUri + ")";
105 }
106 }