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.processor;
018    
019    import org.apache.camel.Exchange;
020    import org.apache.camel.Expression;
021    import org.apache.camel.Message;
022    import org.apache.camel.Processor;
023    import org.apache.camel.Traceable;
024    import org.apache.camel.impl.DefaultMessage;
025    import org.apache.camel.support.ServiceSupport;
026    
027    /**
028     * A processor which sets the body on the IN message with an {@link Expression}
029     */
030    public class SetBodyProcessor extends ServiceSupport implements Processor, Traceable {
031        private final Expression expression;
032    
033        public SetBodyProcessor(Expression expression) {
034            this.expression = expression;
035        }
036    
037        public void process(Exchange exchange) throws Exception {
038            Object newBody = expression.evaluate(exchange, Object.class);
039    
040            Message old = exchange.getIn();
041    
042            // create a new message container so we do not drag specialized message objects along
043            Message msg = new DefaultMessage();
044            msg.copyFrom(old);
045            msg.setBody(newBody);
046            exchange.setIn(msg);
047        }
048    
049        @Override
050        public String toString() {
051            return "SetBody(" + expression + ")";
052        }
053    
054        public String getTraceLabel() {
055            return "setBody[" + expression + "]";
056        }
057    
058        @Override
059        protected void doStart() throws Exception {
060            // noop
061        }
062    
063        @Override
064        protected void doStop() throws Exception {
065            // noop
066        }
067    }