/*
Simple Servlet Example using a stylesheet parameter
 */
package servlet;
// Imported TraX classes
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.stream.StreamSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerConfigurationException;

// Imported SAX classes
import org.xml.sax.SAXException;

// Imported java.io and javax.servlet classes
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class UseStylesheetParamServlet extends HttpServlet {
	
	PrintWriter out;
	String xslFile, xmlFile, paramValue;
	public void doGet(HttpServletRequest req,
		HttpServletResponse res)
			throws ServletException, IOException {
		try {
			res.setContentType("text/html; charset=UTF-8");
			out = res.getWriter();

      paramValue = req.getParameter("PVAL");
			xmlFile    = req.getParameter("XML");
			xslFile    = req.getParameter("XSL");
 		if (paramValue == null) {
			out.println(
			"<h1>No input for paramValue</h1>");
			return;
		}
 		if ( xmlFile == null) {
			out.println(
			"<h1>No input for xmlFile</h1>");
			return;
		}	
		if ( xslFile == null) {
			out.println(
			"<h1>No input for xslFile</h1>");
			return;
		}
		TransformerFactory tFactory =
			TransformerFactory.newInstance();
		Transformer transformer =
			tFactory.newTransformer(new StreamSource(xslFile));

    // Set the stylesheet parameter (named param1).
			transformer.setParameter("param1", paramValue);
    // Perform the transformation.
			transformer.transform(new StreamSource(xmlFile),
					                  new StreamResult(out));
		}		
    catch (IOException e) {			
			e.printStackTrace();
			System.exit(-1);
		}
		catch (TransformerException e) {
      e.printStackTrace(out);
			return;
		}
	}
}