Java tutorial
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ package color; import com.google.gson.JsonArray; import com.google.gson.JsonObject; import java.io.IOException; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.SQLNonTransientConnectionException; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import support.DBHelper; /** * * @author bhaumik */ public class GetColorMaster 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 { final DBHelper helper = DBHelper.GetDBHelper(); final Connection dataConnection = helper.getConnMpAdmin(); final JsonObject jResultObj = new JsonObject(); if (dataConnection != null) { try { String sql = "select COLOUR_CD,COLOUR_NAME,USER_ID from COLOURMST"; PreparedStatement pstLocal = dataConnection.prepareStatement(sql); ResultSet rsLocal = pstLocal.executeQuery(); JsonArray array = new JsonArray(); while (rsLocal.next()) { JsonObject object = new JsonObject(); object.addProperty("COLOUR_CD", rsLocal.getString("COLOUR_CD")); object.addProperty("COLOUR_NAME", rsLocal.getString("COLOUR_NAME")); object.addProperty("USER_ID", rsLocal.getInt("USER_ID")); array.add(object); } jResultObj.addProperty("result", 1); jResultObj.addProperty("Cause", "success"); jResultObj.add("data", array); } catch (SQLNonTransientConnectionException ex1) { jResultObj.addProperty("result", -1); jResultObj.addProperty("Cause", "Server is down"); } catch (SQLException ex) { jResultObj.addProperty("result", -1); jResultObj.addProperty("Cause", ex.getMessage()); } } response.getWriter().print(jResultObj); } // <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> }