XMLServlet

package c3.servlet;

import c3.xml.XMLWriter;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import org.xml.sax.*;

/**
 * An abstract class from which each example servlet extends. This class wraps the XML creation
 * (delegated to the child servlet class) and submission back through the HTTP response.
 *
 */
public abstract class XMLServlet extends HttpServlet {

	private String _encoding_output;

	public XMLServlet() {
	}

	public void init(ServletConfig config) throws ServletException {
		super.init(config);
		if((_encoding_output = getInitParameter("encoding.output")) == null)
			_encoding_output = "utf-8";
	}

	protected long getLastModified(HttpServletRequest req) {
		return -1L;
	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
	throws ServletException, IOException {

		// Set content to xml
		response.setContentType("text/xml; charset="+ _encoding_output);
		response.setHeader("Cache-Control", "no-cache");
		PrintWriter out = response.getWriter();
		try {
			XMLWriter handler = new XMLWriter(out, _encoding_output);
			handler.setPrettyPrinting(true);
			getContent(handler);
			out.flush();
			out.close();
		} catch (SAXException e) {
			response.sendError(HttpServletResponse.SC_FORBIDDEN, e.getMessage());
		}

	}

	public void doGet(HttpServletRequest request, HttpServletResponse response)
		throws ServletException, IOException {
		doPost(request, response);
	}

	/**
	 * Each child class should override this method to generate the specific XML content necessary for each AJAX action.
	 */
	public abstract void getContent(ContentHandler handler) throws SAXException;

}