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 org.apache.camel.Consumer;
020    import org.apache.camel.Exchange;
021    import org.apache.camel.Processor;
022    import org.apache.camel.spi.ExceptionHandler;
023    
024    /**
025     * An {@link ExceptionHandler} that uses the {@link DefaultConsumer} to
026     * process the caused exception to send the message into the Camel routing engine
027     * which allows to let the routing engine handle the exception.
028     * <p/>
029     * An endpoint can be configured with <tt>consumer.bridgeErrorHandler=true</tt> in the URI
030     * to enable this {@link BridgeExceptionHandlerToErrorHandler} on the consumer.
031     * The consumer must extend the {@link DefaultConsumer}, to support this, if not an
032     * {@link IllegalArgumentException} is thrown upon startup.
033     */
034    public class BridgeExceptionHandlerToErrorHandler implements ExceptionHandler {
035    
036        private final LoggingExceptionHandler fallback;
037        private final Consumer consumer;
038        private final Processor bridge;
039    
040        public BridgeExceptionHandlerToErrorHandler(DefaultConsumer consumer) {
041            this.consumer = consumer;
042            this.fallback = new LoggingExceptionHandler(consumer.getClass());
043            this.bridge = consumer.getProcessor();
044        }
045    
046        @Override
047        public void handleException(Throwable exception) {
048            handleException(null, exception);
049        }
050    
051        @Override
052        public void handleException(String message, Throwable exception) {
053            handleException(message, null, exception);
054        }
055    
056        @Override
057        public void handleException(String message, Exchange exchange, Throwable exception) {
058            if (exchange == null) {
059                exchange = consumer.getEndpoint().createExchange();
060            }
061    
062            // set the caused exception
063            exchange.setException(exception);
064            // and the message
065            exchange.getIn().setBody(message);
066            // and mark as redelivery exhausted as we cannot do redeliveries
067            exchange.setProperty(Exchange.REDELIVERY_EXHAUSTED, Boolean.TRUE);
068    
069            try {
070                bridge.process(exchange);
071            } catch (Exception e) {
072                fallback.handleException("Error handling exception " + exception.getMessage(), exchange, e);
073            }
074        }
075    }