franta-hg@11: package cz.frantovo.sql.vyuka.ajax;
franta-hg@11: 
franta-hg@11: import java.io.IOException;
franta-hg@11: import java.io.PrintWriter;
franta-hg@11: import javax.servlet.ServletException;
franta-hg@11: import javax.servlet.http.HttpServlet;
franta-hg@11: import javax.servlet.http.HttpServletRequest;
franta-hg@11: import javax.servlet.http.HttpServletResponse;
franta-hg@11: 
franta-hg@11: /**
franta-hg@11:  * Servlet pro vyřizování AJAXových požadavků.
franta-hg@11:  * @author fiki
franta-hg@11:  */
franta-hg@11: public class Servlet extends HttpServlet {
franta-hg@11: 
franta-hg@11:     private static final long serialVersionUID = 9102108273105288056L;
franta-hg@11: 
franta-hg@11:     private enum akce {
franta-hg@11: 
franta-hg@11:         /** Provede SQL dotaz. */
franta-hg@11:         vykonat,
franta-hg@11:         /** Vypíše historii SQL příkazů daného uživatele. */
franta-hg@11:         historie,
franta-hg@11:         /** Vypíše nějaké nepotřebné informace. */
franta-hg@11:         test,
franta-hg@11:         /** Pokud je požadovaná akce nesmysl. */
franta-hg@11:         chyba
franta-hg@11:     }
franta-hg@11: 
franta-hg@11:     /** 
franta-hg@11:      * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
franta-hg@11:      * @param request servlet request
franta-hg@11:      * @param response servlet response
franta-hg@11:      * @throws ServletException if a servlet-specific error occurs
franta-hg@11:      * @throws IOException if an I/O error occurs
franta-hg@11:      */
franta-hg@11:     protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
franta-hg@12: 
franta-hg@11:         /** Používáme pouze UTF-8 */
franta-hg@11:         response.setContentType("text/html;charset=UTF-8");
franta-hg@11:         request.setCharacterEncoding("UTF-8");
franta-hg@11: 
franta-hg@11:         PrintWriter out = response.getWriter();
franta-hg@12: 
franta-hg@11:         try {
franta-hg@11: 
franta-hg@11:             akce parametrAkce = akce.chyba;
franta-hg@11:             try {
franta-hg@11:                 parametrAkce = akce.valueOf(request.getParameter("akce"));
franta-hg@11:             } catch (Exception e) {
franta-hg@11:                 /** Chyba nebo podvržený AJAXový požadavek → zobrazíme chybovou hlášku */
franta-hg@11:             }
franta-hg@11: 
franta-hg@12: 
franta-hg@11:             Ajax a = new Ajax();
franta-hg@12:             String idSezeni = request.getRequestedSessionId();
franta-hg@11: 
franta-hg@11: 
franta-hg@11:             switch (parametrAkce) {
franta-hg@11:                 case vykonat:
franta-hg@12:                     out.println(a.geSQLVysledek(request.getParameter("sql"), idSezeni));
franta-hg@11:                     break;
franta-hg@11:                 case historie:
franta-hg@12:                     out.println(a.getHistorie(idSezeni));
franta-hg@11:                     break;
franta-hg@11:                 case test:
franta-hg@11:                     out.println("<p>AJAX jede!</p>");
franta-hg@11:                     out.println("<ol>");
franta-hg@11:                     out.println("<li>Metoda: " + request.getMethod() + "</li>");
franta-hg@11:                     out.println("<li>Host: " + request.getRemoteHost() + "</li>");
franta-hg@11:                     out.println("<li>Adresa: " + request.getRemoteAddr() + "</li>");
franta-hg@11:                     out.println("<li>Akce: " + request.getParameter("akce") + "</li>");
franta-hg@11:                     out.println("<li>SQL: " + request.getParameter("sql") + "</li>");
franta-hg@11:                     out.println("<li>Sezení: " + request.getRequestedSessionId() + "</li>");
franta-hg@11:                     out.println("<li>URL: " + request.getRequestURL().toString() + "</li>");
franta-hg@11:                     out.println("</ol>");
franta-hg@11:                     break;
franta-hg@11:                 case chyba:
franta-hg@11:                     out.println("<p>chyba</p>");
franta-hg@11:                     break;
franta-hg@11:             }
franta-hg@11:         } finally {
franta-hg@11:             out.close();
franta-hg@11:         }
franta-hg@11:     }
franta-hg@11: 
franta-hg@11:     // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
franta-hg@11:     /** 
franta-hg@11:      * Handles the HTTP <code>GET</code> method.
franta-hg@11:      * @param request servlet request
franta-hg@11:      * @param response servlet response
franta-hg@11:      * @throws ServletException if a servlet-specific error occurs
franta-hg@11:      * @throws IOException if an I/O error occurs
franta-hg@11:      */
franta-hg@11:     @Override
franta-hg@11:     protected void doGet(HttpServletRequest request, HttpServletResponse response)
franta-hg@11:             throws ServletException, IOException {
franta-hg@11:         processRequest(request, response);
franta-hg@11:     }
franta-hg@11: 
franta-hg@11:     /** 
franta-hg@11:      * Handles the HTTP <code>POST</code> method.
franta-hg@11:      * @param request servlet request
franta-hg@11:      * @param response servlet response
franta-hg@11:      * @throws ServletException if a servlet-specific error occurs
franta-hg@11:      * @throws IOException if an I/O error occurs
franta-hg@11:      */
franta-hg@11:     @Override
franta-hg@11:     protected void doPost(HttpServletRequest request, HttpServletResponse response)
franta-hg@11:             throws ServletException, IOException {
franta-hg@11:         processRequest(request, response);
franta-hg@11:     }
franta-hg@11: 
franta-hg@11:     /** 
franta-hg@11:      * Returns a short description of the servlet.
franta-hg@11:      * @return a String containing servlet description
franta-hg@11:      */
franta-hg@11:     @Override
franta-hg@11:     public String getServletInfo() {
franta-hg@11:         return "Servlet pro zpracování AJAXových požadavků.";
franta-hg@11:     }// </editor-fold>
franta-hg@11: }