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.Exchange; 021 import org.apache.camel.Expression; 022 import org.apache.camel.LoggingLevel; 023 import org.apache.camel.Predicate; 024 import org.apache.camel.Processor; 025 import org.apache.camel.processor.DeadLetterChannel; 026 import org.apache.camel.processor.Logger; 027 import org.apache.camel.processor.RecipientList; 028 import org.apache.camel.processor.RedeliveryPolicy; 029 import org.apache.camel.processor.SendProcessor; 030 import org.apache.camel.spi.RouteContext; 031 import org.apache.commons.logging.LogFactory; 032 033 /** 034 * A builder of a <a 035 * href="http://camel.apache.org/dead-letter-channel.html">Dead Letter 036 * Channel</a> 037 * 038 * @version $Revision: 792966 $ 039 */ 040 public class DeadLetterChannelBuilder extends DefaultErrorHandlerBuilder { 041 042 public DeadLetterChannelBuilder() { 043 // no-arg constructor used by Spring DSL 044 } 045 046 public DeadLetterChannelBuilder(Endpoint deadLetter) { 047 setDeadLetter(deadLetter); 048 } 049 050 public DeadLetterChannelBuilder(String uri) { 051 setDeadLetterUri(uri); 052 } 053 054 public Processor createErrorHandler(RouteContext routeContext, Processor processor) throws Exception { 055 DeadLetterChannel answer = new DeadLetterChannel(processor, getLogger(), getOnRedelivery(), getRedeliveryPolicy(), 056 getHandledPolicy(), getExceptionPolicyStrategy(), getFailureProcessor(), getDeadLetterUri(), 057 isUseOriginalMessage()); 058 // configure error handler before we can use it 059 configure(answer); 060 return answer; 061 } 062 063 public boolean supportTransacted() { 064 return false; 065 } 066 067 // Properties 068 // ------------------------------------------------------------------------- 069 070 public Processor getFailureProcessor() { 071 if (failureProcessor == null) { 072 if (deadLetter != null) { 073 failureProcessor = new SendProcessor(deadLetter); 074 } else { 075 // use a recipient list since we only have an uri for the endpoint 076 failureProcessor = new RecipientList(new Expression() { 077 public Object evaluate(Exchange exchange) { 078 return deadLetterUri; 079 } 080 081 public <T> T evaluate(Exchange exchange, Class<T> type) { 082 return exchange.getContext().getTypeConverter().convertTo(type, deadLetterUri); 083 } 084 }); 085 } 086 } 087 return failureProcessor; 088 } 089 090 protected Predicate createHandledPolicy() { 091 // should be handled by default for dead letter channel 092 return PredicateBuilder.toPredicate(ExpressionBuilder.constantExpression(true)); 093 } 094 095 @Override 096 protected RedeliveryPolicy createRedeliveryPolicy() { 097 return new RedeliveryPolicy(); 098 } 099 100 protected Logger createLogger() { 101 return new Logger(LogFactory.getLog(DeadLetterChannel.class), LoggingLevel.ERROR); 102 } 103 104 @Override 105 public String toString() { 106 return "DeadLetterChannelBuilder(" + deadLetterUri + ")"; 107 } 108 }