/*
* @(#)$Id: TransformServlet.java,v 1.4 2003/01/30 15:59:25 zongaro Exp $
*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2001-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xalan" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 2001, Sun
* Microsystems., http://www.sun.com. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* @author Morten Jorgensen
* @author Jacek Ambroziak
*
*/
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.xalan.xsltc.dom.DOMImpl;
import org.apache.xalan.xsltc.dom.DocumentCache;
import org.apache.xalan.xsltc.runtime.AbstractTranslet;
import org.apache.xalan.xsltc.runtime.output.TransletOutputHandlerFactory;
import org.xml.sax.SAXException;
/**
* This servlet demonstrates how XSL transformations can be made available as
* a web service. See the CompileServlet for an example on how stylesheets
* can be pre-compiled before this servlet is invoked.
*
* Note that the XSLTC transformation engine is invoked through its native
* interface and not the javax.xml.transform (JAXP) interface. This because
* XSLTC still does not offer precompiled transformations through JAXP.
*/
public final class TransformServlet extends HttpServlet {
/*
* This is a document cache with 32 document slots. This servlet returns
* cache statistics if the 'stats' parameter is passed with the HTTP
* request in doGet().
*/
private static DocumentCache cache = null;
/**
* Main servlet entry point
*/
public void doGet(HttpServletRequest request,
HttpServletResponse response)
throws IOException, ServletException {
// Initialise the output writer
response.setContentType("text/html");
PrintWriter out = response.getWriter();
// Get the two paramters "class" and "source".
String className = request.getParameter("class");
String documentURI = request.getParameter("source");
try {
// Initialize document cache with 32 DOM slots
if (cache == null) cache = new DocumentCache(32);
if (request.getParameter("stats") != null) {
cache.getStatistics(out);
}
else if ((className == null) || (documentURI == null)) {
out.println("<h1>XSL transformation error</h1>");
out.println("The parameters <b><tt>class</tt></b> and " +
"<b><tt>source</tt></b> must be specified");
}
else {
// Get a reference to the translet class (not object yet)
Class tc = Class.forName(className);
// Instanciate a translet object (inherits AbstractTranslet)
AbstractTranslet translet = (AbstractTranslet)tc.newInstance();
// Set the document cache for the translet. This is needed in
// case the translet uses the document() function.
translet.setDOMCache(cache);
// Read input document from the DOM cache
DOMImpl dom = cache.retrieveDocument(documentURI, 0, translet);
// Create output handler
TransletOutputHandlerFactory tohFactory =
TransletOutputHandlerFactory.newInstance();
tohFactory.setOutputType(TransletOutputHandlerFactory.STREAM);
tohFactory.setEncoding(translet._encoding);
tohFactory.setOutputMethod(translet._method);
tohFactory.setWriter(out);
// Start the transformation
final long start = System.currentTimeMillis();
translet.transform(dom, tohFactory.getTransletOutputHandler());
final long done = System.currentTimeMillis() - start;
out.println("<!-- transformed by XSLTC in "+done+"msecs -->");
}
}
catch (IOException e) {
out.println("<h1>Error</h1>");
out.println("Could not locate source document: " + documentURI);
out.println(e.toString());
}
catch (ClassNotFoundException e) {
out.println("<h1>Error</h1>");
out.println("Could not locate the translet class: " + className);
out.println(e.toString());
}
catch (SAXException e) {
out.println("<h1>Error</h1>");
out.println("Error parsing document " + documentURI);
}
catch (Exception e) {
out.println("<h1>Error</h1>");
out.println(e.toString());
}
}
}