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 */
017package org.apache.camel.processor;
018
019import java.io.ByteArrayOutputStream;
020
021import org.apache.camel.AsyncCallback;
022import org.apache.camel.AsyncProcessor;
023import org.apache.camel.CamelContext;
024import org.apache.camel.CamelContextAware;
025import org.apache.camel.Exchange;
026import org.apache.camel.Message;
027import org.apache.camel.Traceable;
028import org.apache.camel.converter.stream.CachedOutputStream;
029import org.apache.camel.spi.DataFormat;
030import org.apache.camel.support.ServiceSupport;
031import org.apache.camel.util.AsyncProcessorHelper;
032import org.apache.camel.util.ObjectHelper;
033import org.apache.camel.util.ServiceHelper;
034
035/**
036 * Marshals the body of the incoming message using the given
037 * <a href="http://camel.apache.org/data-format.html">data format</a>
038 *
039 * @version
040 */
041public class MarshalProcessor extends ServiceSupport implements AsyncProcessor, Traceable, CamelContextAware {
042    private CamelContext camelContext;
043    private final DataFormat dataFormat;
044
045    public MarshalProcessor(DataFormat dataFormat) {
046        this.dataFormat = dataFormat;
047    }
048
049    public void process(Exchange exchange) throws Exception {
050        AsyncProcessorHelper.process(this, exchange);
051    }
052
053    public boolean process(Exchange exchange, AsyncCallback callback) {
054        ObjectHelper.notNull(dataFormat, "dataFormat");
055
056        // if stream caching is enabled then use that so we can stream accordingly
057        // for example to overflow to disk for big streams
058        CachedOutputStream cos;
059        ByteArrayOutputStream os;
060        if (exchange.getContext().getStreamCachingStrategy().isEnabled()) {
061            cos = new CachedOutputStream(exchange);
062            os = null;
063        } else {
064            cos = null;
065            os = new ByteArrayOutputStream();
066        }
067
068        Message in = exchange.getIn();
069        Object body = in.getBody();
070
071        // lets setup the out message before we invoke the dataFormat
072        // so that it can mutate it if necessary
073        Message out = exchange.getOut();
074        out.copyFrom(in);
075
076        try {
077            if (cos != null) {
078                dataFormat.marshal(exchange, body, cos);
079                out.setBody(cos.newStreamCache());
080            } else {
081                dataFormat.marshal(exchange, body, os);
082                byte[] data = os.toByteArray();
083                out.setBody(data);
084            }
085        } catch (Exception e) {
086            // remove OUT message, as an exception occurred
087            exchange.setOut(null);
088            exchange.setException(e);
089        }
090
091        callback.done(true);
092        return true;
093    }
094
095    @Override
096    public String toString() {
097        return "Marshal[" + dataFormat + "]";
098    }
099
100    public String getTraceLabel() {
101        return "marshal[" + dataFormat + "]";
102    }
103
104    public CamelContext getCamelContext() {
105        return camelContext;
106    }
107
108    public void setCamelContext(CamelContext camelContext) {
109        this.camelContext = camelContext;
110    }
111
112    @Override
113    protected void doStart() throws Exception {
114        // inject CamelContext on data format
115        if (dataFormat instanceof CamelContextAware) {
116            ((CamelContextAware) dataFormat).setCamelContext(camelContext);
117        }
118        ServiceHelper.startService(dataFormat);
119    }
120
121    @Override
122    protected void doStop() throws Exception {
123        ServiceHelper.stopService(dataFormat);
124    }
125}