java lang NumberFormatException null i

0 votes

I am getting this error while doing operations like update, delete and insert. But it gives an exception of null. The following are the error and the code I have used.

Error:

HTTP Status 500 - null

type Exception report

message null

description The server encountered an internal error that prevented it from fulfilling this request.

exception

java.lang.NumberFormatException: null
    java.lang.Integer.parseInt(Integer.java:454)
    java.lang.Integer.parseInt(Integer.java:527)
    Controller.ControllerTest.doGet(ControllerTest.java:48)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.37 logs.

Apache Tomcat/6.0.37

user.jsp:

<form method="POST" action='ControllerTest' name="frmAddUser">

  <jsp:useBean id="users" class="java.util.ArrayList" scope="request" />
        <% for(int i = 0; i < users.size(); i+=1) 
        { 
            UseBean user = (UseBean)users.get(i);
        %>

        id:<input type="text" name="ID" value="<%=user.getID() %>"><br/>
        Name:<input type="text" name="Name" value="<%= user.getName() %>"><br/>
        Password:<input type="text" name="password" value="<%= user.getPassword() %>"><br/>
        phoneno:<input type="text" name="Phoneo" value="<%= user.getPhoneo() %>"><br/>
        Emailid:<input type="text" name="Emailid" value="<%= user.getEmailID() %>">  <br/> 

        <%} %>
         <input type="submit" value="Submit" />
    </form>

listuser.jsp

  <body>
<table border=1>
<thead>
    <tr>
    <th>Id</th>
    <th>Name</th>
    <th>password</th>
    <th>phoneno</th>
    <th>emailid</th>
    <th colspan=2>Action</th>
    </tr>
</thead>
<tbody>
    <jsp:useBean id="users" class="java.util.ArrayList" scope="request" />
    <% for(int i = 0; i < users.size(); i+=1) 
    { 
        UseBean user = (UseBean)users.get(i);
    %>
        <tr>
        <td><%= user.getID() %></td>
        <td><%= user.getName() %></td>
        <td><%= user.getPassword() %></td>
        <td><%= user.getEmailID() %></td>
        <td><%= user.getPhoneo() %></td>
        <td><a href="ControllerTest?action=edit&userId=<%= user.getID() %>" >Update</a></td>
        <td><a href="ControllerTest?action=delete&userId=<%= user.getID() %>">Delete</a></td>
        </tr>
    <% } %>
</tbody>
</table>
<p>
<a href="ControllerTest?action=insert">Add User</a>
</p>

Controllertest.java:

package Controller;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import dao.UserDao;
import dbBean.UseBean;

public class ControllerTest extends HttpServlet
{
    private static final long serialVersionUID = 1L;
    private static String INSERT_OR_EDIT = "/user.jsp";
    private static String LIST_USER = "/listUser.jsp";

    private UserDao dao;

    public ControllerTest()
    {
        super();
        dao = new UserDao();

    }

    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException
    {

        String forward = "";
        String action = request.getParameter("action");
        if (action.equalsIgnoreCase("delete"))
        {
            try
            {
                int userId = Integer.parseInt(request.getParameter("userId"));
                dao.deleteUser(userId);
                forward = LIST_USER;
                request.setAttribute("users", dao.getAllUsers());
            }
            catch (NumberFormatException ex)
            {

                System.out.println("Error occured with during conversion delete");
            }
        } 
        else if (action.equalsIgnoreCase("edit"))
        {
            forward = INSERT_OR_EDIT;
            try
            {

                int userId = Integer.parseInt(request.getParameter("userId"));
                UseBean bean = dao.getUserById(userId);
                request.setAttribute("user", bean);

            } catch (NumberFormatException ex)
            {

                System.out.println("Error occured with during conversion edit");
            }
        }
        else if (action.equalsIgnoreCase("listUser"))
        {
            forward = LIST_USER;
            request.setAttribute("users", dao.getAllUsers());
        } else
        {
            forward = INSERT_OR_EDIT;
        }
        RequestDispatcher view = request.getRequestDispatcher(forward);
        view.forward(request, response);

    }

    protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException
    {

        try
        {
            UseBean bean = new UseBean();
            bean.setName(request.getParameter("Name"));
            bean.setPassword(request.getParameter("password"));
            bean.setPhoneo(request.getParameter("Phoneo"));
            bean.setEmailID(request.getParameter("Emailid"));
            String userid = request.getParameter("ID");
            if (userid == null || userid.isEmpty())
            {
                dao.addUser(bean);
            } else
            {
                bean.setID(Integer.parseInt(userid));
                dao.updateUser(bean);
            }
            RequestDispatcher view = request.getRequestDispatcher(LIST_USER);
            request.setAttribute("users", dao.getAllUsers());
            view.forward(request, response);

        }

        catch (Exception e)
        {
            e.printStackTrace();
            System.out.println("erro occuring in update code");
        }

    }
}

Can someone look at this code and tell me what I am doing wrong here?

May 13, 2022 in Java by Kichu
• 19,040 points
2,075 views

No answer to this question. Be the first to respond.

Your answer

Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.

Related Questions In Java

0 votes
2 answers

How can I solve java.lang.NoClassDefFoundError in Java?

NoClassDefFoundError means that the class is present ...READ MORE

answered Sep 11, 2018 in Java by Sushmita
• 6,920 points
34,139 views
0 votes
1 answer

How to prevent java.lang.NumberFormatException in Java?

"N/A" is not integer. It must throw NumberFormatException if you ...READ MORE

answered Jun 26, 2018 in Java by sharth
• 3,370 points
4,784 views
0 votes
2 answers

How can I convert a String variable to a primitive int in Java

 Here are two ways illustrating this: Integer x ...READ MORE

answered Aug 20, 2019 in Java by Sirajul
• 59,230 points
2,354 views
0 votes
2 answers

How do I get the current date and time using Java?

If you require a time stamp in ...READ MORE

answered Aug 23, 2019 in Java by Sirajul
• 59,230 points
2,985 views
0 votes
2 answers

How can I create File and write data in it using Java?

import java.io.BufferedWriter; import java.io.IOException; import java.nio.file.Files; import java.nio.file.Paths; public class WriteFiles{ ...READ MORE

answered Jul 26, 2018 in Java by samarth295
• 2,220 points
2,962 views
0 votes
1 answer

I am learning looping statements. Can you tell me how 'for-each' works in Java?

While programming we often write code that ...READ MORE

answered Apr 17, 2018 in Java by Rishabh
• 3,620 points
951 views
0 votes
1 answer

What are the different methods of session management in servlets?

Session is a conversational state between client ...READ MORE

answered Feb 18, 2019 in Java by Frankie
• 9,830 points
19,720 views
0 votes
1 answer
0 votes
0 answers

java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver

I am getting this exception when I ...READ MORE

May 7, 2022 in Java by narikkadan
• 63,600 points
2,464 views
0 votes
1 answer

The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path

Include servlet-api-3.1.jar in your dependencies. Maven <dependency> <groupId>javax.servlet</groupId> ...READ MORE

answered Sep 20, 2022 in Java-Script by Abhinaya
• 1,160 points
2,058 views
webinar REGISTER FOR FREE WEBINAR X
REGISTER NOW
webinar_success Thank you for registering Join Edureka Meetup community for 100+ Free Webinars each month JOIN MEETUP GROUP