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 java.io.InputStream;
020    
021    import org.apache.camel.CamelContext;
022    import org.apache.camel.CamelContextAware;
023    import org.apache.camel.Exchange;
024    import org.apache.camel.Message;
025    import org.apache.camel.Processor;
026    import org.apache.camel.RuntimeCamelException;
027    import org.apache.camel.Traceable;
028    import org.apache.camel.spi.DataFormat;
029    import org.apache.camel.support.ServiceSupport;
030    import org.apache.camel.util.IOHelper;
031    import org.apache.camel.util.ObjectHelper;
032    import org.apache.camel.util.ServiceHelper;
033    
034    /**
035     * Unmarshals the body of the incoming message using the given
036     * <a href="http://camel.apache.org/data-format.html">data format</a>
037     *
038     * @version 
039     */
040    public class UnmarshalProcessor extends ServiceSupport implements Processor, Traceable, CamelContextAware {
041        private CamelContext camelContext;
042        private final DataFormat dataFormat;
043    
044        public UnmarshalProcessor(DataFormat dataFormat) {
045            this.dataFormat = dataFormat;
046        }
047    
048        public void process(Exchange exchange) throws Exception {
049            ObjectHelper.notNull(dataFormat, "dataFormat");
050    
051            InputStream stream = exchange.getIn().getMandatoryBody(InputStream.class);
052            try {
053                // lets setup the out message before we invoke the dataFormat so that it can mutate it if necessary
054                Message out = exchange.getOut();
055                out.copyFrom(exchange.getIn());
056    
057                Object result = dataFormat.unmarshal(exchange, stream);
058                if (result instanceof Exchange) {
059                    if (result != exchange) {
060                        // it's not allowed to return another exchange other than the one provided to dataFormat
061                        throw new RuntimeCamelException("The returned exchange " + result + " is not the same as " + exchange + " provided to the DataFormat");
062                    }
063                } else if (result instanceof Message) {
064                    // the dataformat has probably set headers, attachments, etc. so let's use it as the outbound payload
065                    exchange.setOut((Message) result);
066                } else {
067                    out.setBody(result);
068                }
069            } catch (Exception e) {
070                // remove OUT message, as an exception occurred
071                exchange.setOut(null);
072                throw e;
073            } finally {
074                IOHelper.close(stream, "input stream");
075            }
076        }
077    
078        public String toString() {
079            return "Unmarshal[" + dataFormat + "]";
080        }
081    
082        public String getTraceLabel() {
083            return "unmarshal[" + dataFormat + "]";
084        }
085    
086        public CamelContext getCamelContext() {
087            return camelContext;
088        }
089    
090        public void setCamelContext(CamelContext camelContext) {
091            this.camelContext = camelContext;
092        }
093    
094        @Override
095        protected void doStart() throws Exception {
096            // inject CamelContext on data format
097            if (dataFormat instanceof CamelContextAware) {
098                ((CamelContextAware) dataFormat).setCamelContext(camelContext);
099            }
100            ServiceHelper.startService(dataFormat);
101        }
102    
103        @Override
104        protected void doStop() throws Exception {
105            ServiceHelper.stopService(dataFormat);
106        }
107    
108    }