topicservlet.java

仿校内网站

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import myTools.DataBase;

/**
 *
 * @author Administrator
 */
public class TopicServlet extends HttpServlet {
   
    /** 
    * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
    * @param request servlet request
    * @param response servlet response
    */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        String operation = request.getParameter("operation");
        System.out.println(operation);
        DataBase db = new DataBase();
        ResultSet rs = null;
        db.connectToDB();
        try {
            if(operation ==null){
                System.out.println("TOPIC SERVLET ERROR");
            }else if(operation.equals("create")){
                String topic_maker_id = request.getParameter("maker_id");
                String des = new String(request.getParameter("textarea").getBytes("ISO-8859-1"),"GB2312");
                String a = new String(request.getParameter("textfield1").getBytes("ISO-8859-1"),"gb2312");
                String b = new String(request.getParameter("textfield2").getBytes("ISO-8859-1"),"gb2312");
                String c = new String(request.getParameter("textfield3").getBytes("ISO-8859-1"),"gb2312");
                String d = new String(request.getParameter("textfield4").getBytes("ISO-8859-1"),"gb2312");
                String e = new String(request.getParameter("textfield5").getBytes("ISO-8859-1"),"gb2312");
                String sql = "insert into topics (topic_maker_id, topic_description, a, b, c, d, e) values ('" +
                        topic_maker_id + "', '" + des + "' '" + a + "', '" + b + "', '" + c + "', '" + d + "', '" + e + "')";
 
                db.executeUpdate(sql);
                 sql = "select topic_id from topics where topic_description = " + des;
                 rs = db.executeQuery(sql);
                 String id = "";
                 try{
                    if(rs.next()){
                        id = rs.getString(1);
                    }
                }catch(Exception ee){
                   System.out.println(id);
                }
                response.sendRedirect("vote.jsp?id="+id);
            }else if(operation.equals("vote")){
                String topic_id = request.getParameter("topic_id");
                String yes = request.getParameter("RadioGroup1");
                String sql = "select " + yes + " from topics where topic_id = " + topic_id;
                rs = db.executeQuery(sql);
                System.out.println(sql);
                int number=0;
                try{
                    if(rs.next()){
                        number = rs.getInt(1);
                        number ++;
                        sql = "update topics set " + yes + " = " + number + " where topic_id = " + topic_id;
                        System.out.println(sql);
                        db.executeUpdate(sql);
                        response.sendRedirect("vote.jsp?id="+topic_id);
                    }
                }catch(SQLException e){
                    System.out.println("VOTE ERROR");
                }
               
            }
            
        } finally { 
            db.close();
            out.close();
        }
    } 

    // <editor-fold defaultstate="collapsed" desc="HttpServlet 方法。单击左侧的 + 号以编辑代码。">
    /** 
    * Handles the HTTP <code>GET</code> method.
    * @param request servlet request
    * @param response servlet response
    */
    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
    */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
    * Returns a short description of the servlet.
    */
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>

}