Andrej Cimperšek - diploma

package org.lidar;

import com.google.gson.Gson;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.ArrayList;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.hibernate.Query;

import org.hibernate.Session;

import org.hibernate.Transaction;

import org.lidar.HibernateUtil;

/**

 * Log Servlet

 * @author Andrej Cimpersek

 */

public class LogServlet extends HttpServlet {

    /**

     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.

     * @param request servlet request

     * @param response servlet response

     * @throws ServletException if a servlet-specific error occurs

     * @throws IOException if an I/O error occurs

     */

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {

        response.setContentType("application/json;charset=UTF-8");

        PrintWriter out = response.getWriter();

        Gson gson = new Gson();

        try {

            int start = 0;

            int limit = 15;

            if (request.getParameter("limit") != null) {

                limit = Integer.parseInt(request.getParameter("limit"));

            }

            if (request.getParameter("start") != null) {

                start = Integer.parseInt(request.getParameter("start"));

            }

            Session session = HibernateUtil.getSessionFactory().getCurrentSession();

            Transaction tx = session.beginTransaction();

            // FIX: use COUNT instead

            int total = session.createQuery("from Log as log").list().size();

            Query query = session.createQuery("from Log as log order by log.date desc");

            query.setFirstResult(start);

            query.setMaxResults(limit);

            JSONResponse resp = new JSONResponse(true, total, (ArrayList) query.list());

            out.write(gson.toJson(resp));

            tx.commit();

        } catch (Exception e) {

            response.setContentType("text/plain;charset=UTF-8");

            out.write(e.getMessage());

        } finally {

            out.close();

        }

    }

    class JSONResponse {

        private boolean success = true;

        private int total;

        private ArrayList rows;

        public JSONResponse(boolean success, int total, ArrayList rows) {

            this.success = success;

            this.total = total;

            this.rows = rows;

        }

    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">

    /**

     * Handles the HTTP <code>GET</code> method.

     * @param request servlet request

     * @param response servlet response

     * @throws ServletException if a servlet-specific error occurs

     * @throws IOException if an I/O error occurs

     */

    @Override

    protected void doGet(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {

        processRequest(request, response);

    }

    /**

     * Handles the HTTP <code>POST</code> method.

     * @param request servlet request

     * @param response servlet response

     * @throws ServletException if a servlet-specific error occurs

     * @throws IOException if an I/O error occurs

     */

    @Override

    protected void doPost(HttpServletRequest request, HttpServletResponse response)

            throws ServletException, IOException {

        processRequest(request, response);

    }

    /**

     * Returns a short description of the servlet.

     * @return a String containing servlet description

     */

    @Override

    public String getServletInfo() {

        return "Short description";

    }// </editor-fold>

}