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 import org.apache.camel.util.ObjectHelper; 027 028 /** 029 * A processor which sets the body on the OUT message with an {@link Expression} 030 */ 031 public class TransformProcessor extends ServiceSupport implements Processor, Traceable { 032 private final Expression expression; 033 034 public TransformProcessor(Expression expression) { 035 ObjectHelper.notNull(expression, "expression", this); 036 this.expression = expression; 037 } 038 039 public void process(Exchange exchange) throws Exception { 040 Object newBody = expression.evaluate(exchange, Object.class); 041 042 Message old = exchange.getIn(); 043 044 // create a new message container so we do not drag specialized message objects along 045 Message msg = new DefaultMessage(); 046 msg.copyFrom(old); 047 msg.setBody(newBody); 048 exchange.setOut(msg); 049 } 050 051 @Override 052 public String toString() { 053 return "Transform(" + expression + ")"; 054 } 055 056 public String getTraceLabel() { 057 return "transform[" + expression + "]"; 058 } 059 060 @Override 061 protected void doStart() throws Exception { 062 // noop 063 } 064 065 @Override 066 protected void doStop() throws Exception { 067 // noop 068 } 069 }