Zusammenfassung POST und GET-Methode
Es ist vorteilhaft die vom JSDK gebotenen Methoden doGet und doPost
zu einer Methode doRequest zusammenzufassen und alle Servlets von
der Klasse BaseUserActionabzuleiten.

package xxx;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;

/**
 * <b>Klassenname:</b> BaseUserAction<br>
 * <br>
 * <b>Subsystem:</b> Frontend<br>
 * <br>
 * <b>Zugehöriger UseCase:</b> übergreifend<br>
 * <br>
 * <b>Beschreibung:</b> Abstract class for all user actions. <br>
 * <br>
 *
 * @author xxx
 * @version xxx
 */
public abstract class BaseUserAction extends HttpServlet
{
    /**
     * Forwards Request to doRequest to avoid double implementation in
     * doGet/doPost. <br><br>
     *
     * @param req Servlet Request
     * @param resp Servlet Response
     * @return -
     */
    public void doGet(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, java.io.IOException {
       doRequest(req, resp);
    } // end doGet

    /**
     * Forwards Request to doRequest to avoid double implementation in
     * doGet/doPost. <br><br>
     *
     * @param req Servlet Request
     * @param resp Servlet Response
     * @return -
     */
    public void doPost(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, java.io.IOException {
       doRequest(req, resp);
    } // end doPost

	 /**
     * Execute action.
     *  Overwrite this method to implement the background processing (application logic) and then
     *  to forward execution to the JSP file. <br><br>
     *
     * @param req HTTP request
     * @param resp HTTP response
     * @return -
     **/
    protected abstract void doRequest(HttpServletRequest req, HttpServletResponse resp)
      throws ServletException, java.io.IOException;
}