error in web application

In your application when i am trying to execute it from the below page

<%@ page language="java" import="java.util.*;"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
 <HEAD>
  <TITLE>Servlet Application</TITLE>

  <script language="javascript">
function editRecord(id){

    window.location.href="UserServlet/"+id; 
  }


  function deleteRecord(id){

    window.location.href="deleteUser/"+id; 
  }
</script>
 </HEAD>

 <BODY>
 <br>
<table align="center">

</table>
<br>
  <table width="600px"  align="center" style="background-color:#EDF6EA;border:1px solid #000000;">
 <tr><td colspan=9 align="center" height="10px"></td></tr>

    <tr><td colspan=9 align="center"><a href="addUser.jsp" style="font-weight:bold;color:#cc0000;">Add New User</a></td></tr>
<tr><td colspan=9 align="center" height="10px"></td></tr>
  <tr style="background-color:#7BA88B;font-weight:bold;">
     <td>User Id</td><td>UserName</td><td>First Name</td>
     <td>Last Name</td><td>City</td><td>Sate</td>
     <td>Country</td><td>Edit</td><td>Delete</td>
  </tr>
    <%
    String bgcolor="";
    int count=0;
    List viewList = new ArrayList();
    Iterator  viewItr;

    if(request.getAttribute("userList")!=null && request.getAttribute("userList")!="")
    {
        List userList =  (ArrayList)request.getAttribute("userList");
        Iterator itr = userList.iterator();

        while(itr.hasNext())
        {

            if(count%2==0)
            {
             bgcolor = "#C8E2D1";
            }
            else
            {

                bgcolor = "#EAF8EF";
            }

            viewList = (ArrayList)itr.next();
            int id = Integer.parseInt(viewList.get(0).toString());
            viewItr = viewList.iterator();
            %>
            <tr style="background-color:<%=bgcolor%>;">
            <%  
            while(viewItr.hasNext())
            {

                %>
                <td><%=viewItr.next()%></td>

                <%

            }
            count++;
            %>
            <td><input type="button" name="edit" value="Edit" style="background-color:#49743D;font-weight:bold;color:#ffffff;" onclick="editRecord(<%=id%>);" ></td>
                <td><input type="button" name="delete" style="background-color:#ff0000;font-weight:bold;;color:#ffffff;" value="Delete" onclick="deleteRecord(<%=id%>);"></td>
            </tr>
            <%
        }
    }
    if(count==0)
    {
        %>
        <tr><td colspan="9" align="center">&nbsp;</td></tr>
            <tr><td colspan="9" align="center">No Record Avaliable</td></tr>
        <%
    }
    %>
     <tr><td colspan=9 align="center" height="2px"></td></tr>
  </table>  
 </BODY>
</HTML>

when i click on edit button it is going on follwoing servlet

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

public class UserServlet extends HttpServlet{ 

   public void doGet(HttpServletRequest request, HttpServletResponse response)
                                   throws ServletException,IOException{
            response.setContentType("text/html");
            PrintWriter out = response.getWriter();
            String str[] = request.getRequestURI().toString().split("/");

         int id = Integer.parseInt(str[3]);
            System.out.println("MySQL Connect Example.");
            Connection conn = null;
            String url = "jdbc:mysql://localhost:3306/";
            String dbName = "user_register";
            String driver = "com.mysql.jdbc.Driver";
            String userName = "root"; 
            String password = "root";

        //  out.println(request.getRequestURI());
            Statement st;
            try {
                Class.forName(driver).newInstance();
                conn = DriverManager.getConnection(url+dbName,userName,password);
                System.out.println("Connected to the database");


                ArrayList userList=null;
                String query = "select * from userregister where id="+id;
                System.out.println("query " + query);
                st = conn.createStatement();
                ResultSet  rs = st.executeQuery(query);


                while(rs.next())
                {

                  userList =new ArrayList();
                  userList.add(rs.getInt(1));
                  userList.add(rs.getString(2));
                  userList.add(rs.getString(4));
                  userList.add(rs.getString(5));
                  userList.add(rs.getString(6));
                  userList.add(rs.getString(7));
                  userList.add(rs.getString(8));

                }

                request.setAttribute("userList",userList);

                String nextJSP = "/editUser.jsp";
                RequestDispatcher dispatcher = getServletContext().getRequestDispatcher(nextJSP);
                dispatcher.forward(request,response);
                conn.close();
                System.out.println("Disconnected from database");
            } catch (Exception e) {
            e.printStackTrace();
            }
  }
}

but not redicting to editUser.jsp that is following

<%@ page language="java" import="java.util.*;"%>
<html>
<head>
</head>
<body>
<%!
int id;
String first_name="";
String last_name="";
String username="";
String city="";
String state="";
String country="";
List  userList=null;
%>

<%

if(request.getAttribute("userList")!=null && request.getAttribute("userList")!="")
{
        userList = (ArrayList)request.getAttribute("userList");
        id=Integer.parseInt(userList.get(0).toString());
        username=userList.get(1).toString();
        first_name=userList.get(2).toString();
        last_name=userList.get(3).toString();
        city=userList.get(4).toString();
        state=userList.get(5).toString();
        country=userList.get(6).toString();
        //out.println(id);
}
%>

<form name="userform" method="post" action="../editUser">
<br><br><br>
<table align="center" width="300px" style="background-color:#EDF6EA;border:1px solid #000000;">
<input type="hidden" name="id" value="<%=id%>">
<tr><td colspan=2 style="font-weight:bold;" align="center">Edit User</td></tr>
<tr><td colspan=2 align="center" height="10px"></td></tr>
    <tr>
        <td>First Name</td>
        <td><input type="text" name="first_name" value="<%=first_name%>"></td>
    </tr>
    <tr>
        <td>Last Name</td>
        <td><input type="text" name="last_name" value="<%=last_name%>"></td>
    </tr>
    <tr>
        <td>UserName</td>
        <td><input type="text" name="username" value="<%=username%>"></td>
    </tr>
    <tr>
        <td>Password</td>
        <td><input type="password" name="password" value=""></td>
    </tr>

    <tr>
        <td>City</td>
        <td><input type="text"  name="city" value="<%=city%>"></td>
    </tr>
    <tr>
        <td>State</td>
        <td><input type="text" name="state" value="<%=state%>"></td>
    </tr>
    <tr>
        <td>Country</td>
        <td><input type="text" name="country" value="<%=country%>"></td>
    </tr>

    <tr>
        <td></td>
        <td><input type="submit" name="Submit" value="Edit" style="background-color:#49743D;font-weight:bold;color:#ffffff;"></td>
    </tr>
    <tr><td colspan=2 align="center" height="10px"></td></tr>
</table>
</form>
</body>
</html>

please help me

View Answers

March 28, 2012 at 11:43 AM

We are providing you another application. Check it.

1)application.jsp:

<%@ page import="java.sql.*" %>
<html>
<head>
<script language="javascript">
function editRecord(id){
    var f=document.form;
    f.method="post";
    f.action='edit.jsp?id='+id;
    f.submit();
}
function deleteRecord(id){
    var f=document.form;
    f.method="post";
    f.action='delete.jsp?id='+id;
    f.submit();
}
</script>
</head>
<body>

<br><br>
<form method="post" name="form">
<table border="1">
<tr><th>Name</th><th>Address</th><th>Contact No</th><th>Email</th></tr>
<%
Connection con = null;
String url = "jdbc:mysql://localhost:3306/";
String db = "test";
String driver = "com.mysql.jdbc.Driver";
String userName ="root";
String password="root";

int sumcount=0;
Statement st;
try{
Class.forName(driver).newInstance();
con = DriverManager.getConnection(url+db,userName,password);
String query = "select * from employee";
st = con.createStatement();
ResultSet rs = st.executeQuery(query);
%>

<%
while(rs.next()){
%>
<tr><td><%=rs.getString(2)%></td>
<td><%=rs.getString(3)%></td>
<td><%=rs.getString(4)%></td>
<td><%=rs.getString(5)%></td>
<td><input type="button" name="edit" value="Edit" style="background-color:#49743D;font-weight:bold;color:#ffffff;" onclick="editRecord(<%=rs.getString(1)%>);" ></td>
<td><input type="button" name="delete" value="Delete" style="background-color:#ff0000;font-weight:bold;color:#ffffff;" onclick="deleteRecord(<%=rs.getString(1)%>);" ></td>
</tr>
<%
}
%>
<%
}
catch(Exception e){
e.printStackTrace();
}
%>
</table>
</form>
</body>
</html>

2)edit.jsp:

<%@page language="java"%>
<%@page import="java.sql.*"%>
<form method="post" action="update.jsp">
<table border="1">
<tr><th>Name</th><th>Address</th><th>Contact No</th><th>Email</th></tr>
<%
String id=request.getParameter("id");
int no=Integer.parseInt(id);
int sumcount=0;
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root");
String query = "select * from employee where id='"+no+"'";
Statement st = conn.createStatement();
ResultSet rs = st.executeQuery(query);
while(rs.next()){
%>
<tr>
<td><input type="text" name="name" value="<%=rs.getString("name")%>"></td>
<td><input type="text" name="address" value="<%=rs.getString("address")%>"></td>
<td><input type="text" name="contact" value="<%=rs.getInt("contactNo")%>"></td>
<td><input type="text" name="email" value="<%=rs.getString("email")%>"></td>
<td><input type="hidden" name="id" value="<%=rs.getString(1)%>"></td>
</tr>
<tr>
<td><input type="submit" name="Submit" value="Update" style="background-color:#49743D;font-weight:bold;color:#ffffff;"></td>
</tr>
<%
}
}
catch(Exception e){}
%>
</table>
</form>

March 28, 2012 at 11:44 AM

continue..

3)update.jsp:

<%@page import="java.sql.*"%>

<%
String ide=request.getParameter("id");
int num=Integer.parseInt(ide);
String name=request.getParameter("name");
String address=request.getParameter("address");
int contact=Integer.parseInt(request.getParameter("contact"));
String email=request.getParameter("email");
try{
Connection conn = null;
Class.forName("com.mysql.jdbc.Driver").newInstance();
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root", "root");
Statement st=null;
st=conn.createStatement();
st.executeUpdate("update employee set name='"+name+"',address='"+address+"',contactNo="+contact+",email='"+email+"' where id='"+num+"'");
response.sendRedirect("/examples/jsp/application.jsp");
}
catch(Exception e){
System.out.println(e);
    }
%>

4)delete.jsp:

<%@page import="java.sql.*"%>
<%

String id=request.getParameter("id");
int no=Integer.parseInt(id);
int sumcount=0;
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root");
Statement st = conn.createStatement();
st.executeUpdate("DELETE FROM employee WHERE id = '"+no+"'");
response.sendRedirect("application.jsp");
}
catch(Exception e){}
%>

March 28, 2012 at 12:33 PM

thanx for your help but i need in servlet form as there is lots of other functionality which i have to embed in it..

can you help me with this..

just tell me the way i can extract data from the database in jsp form field but logic i have to apply to apply in servlets only for extraction of database fields and in jsp just i have to print the values extracted through servlet...