viewmessageservlet.java

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package ksnb;

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


public class ViewMessageServlet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=GB2312";
    private Connection con;
    private String cmd;
    private Message message;

    //Initialize global variables
    public void init() throws ServletException {
          message=new Message();
    }

    //Process the HTTP Get request
    public void service(HttpServletRequest request, HttpServletResponse response) throws
            ServletException, IOException {
        cmd=(String)request.getParameter("cmd");
        String page=null;
        //System.out.println(cmd);
        HttpSession session=request.getSession(true);


        if(cmd.equals("1"))
        {
            //System.out.println(cmd);
            page="AddMessage.jsp";
        }
        else if(cmd.equals("2"))
        {
            String id=(String)session.getAttribute("ID");

            message.insert(request);
            message.query(id);
            page="ViewMessage.jsp";

        }
        else
        {
            String id=request.getParameter("id");
            message=new Message();
            message.query(id);
           page="ViewMessage.jsp";

        }
        RequestDispatcher rd = request.getRequestDispatcher(page);
        rd.forward(request, response);

    }

    //Process the HTTP Post request
   /* public void doPost(HttpServletRequest request, HttpServletResponse response) throws
            ServletException, IOException {
        doGet(request, response);
    }*/

    //Clean up resources
    public void destroy() {
    }
}