001    /** 
002     * 
003     * Copyright 2004 Protique Ltd
004     * 
005     * Licensed under the Apache License, Version 2.0 (the "License"); 
006     * you may not use this file except in compliance with the License. 
007     * 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     **/
018    package org.codehaus.activesoap.handler;
019    
020    import javanet.staxutils.StAXResult;
021    import javanet.staxutils.StAXSource;
022    import org.codehaus.activesoap.Handler;
023    import org.codehaus.activesoap.MessageExchange;
024    
025    import javax.xml.stream.XMLStreamReader;
026    import javax.xml.stream.XMLStreamWriter;
027    import javax.xml.transform.Transformer;
028    import javax.xml.transform.TransformerConfigurationException;
029    import javax.xml.transform.TransformerFactory;
030    
031    /**
032     * Pipes the input into some kind of transformer to generate the response
033     *
034     * @version $Revision: 1.4 $
035     */
036    public class TransformHandler implements Handler {
037    
038        private TransformerFactory transformerFactory;
039    
040        public TransformHandler(TransformerFactory transformerFactory) {
041            this.transformerFactory = transformerFactory;
042        }
043    
044        public void invoke(MessageExchange exchange) throws Exception {
045            XMLStreamReader in = exchange.getIn();
046            XMLStreamWriter out = exchange.getOut();
047            Transformer transformer = getTransformer();
048            transformer.transform(new StAXSource(in), new StAXResult(out));
049        }
050    
051        protected Transformer getTransformer() throws TransformerConfigurationException {
052            // a transformer can only be used by one thread at once, so either
053            // cache this using ThreadLocal or just create a new one each time
054            return transformerFactory.newTransformer();
055        }
056    }