This post explains the Registration applications in Java using Servlet, JSP, and MySQL database servers. This Java registration form follows Model View Controller (MVC) architecture. Let us understand what is MVC and how this should be used while developing any application.
For Login application in java, refer to the post Login application in Java using MVC
The Model View Controller (MVC) architecture can be best explained with the help of the following diagram.
We are making use of Eclipse Integrated development environment(IDE) for this Java Registration Application. To follow the basic coding standards, I have created my folder structure as shown in the following diagram.
Login Applications in Java:
Any Registration or Login application always begins with views. It can be a page in HTML, JSP, PHP, VB, or any other language. Our Java Registration application begins with Register.jsp and from Register.jsp we will call RegisterServlet.java class.
Register.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Register</title>
<script>
function validate()
{
var fullname = document.form.fullname.value;
var email = document.form.email.value;
var username = document.form.username.value;
var password = document.form.password.value;
var conpassword= document.form.conpassword.value;
if (fullname==null || fullname=="")
{
alert("Full Name can't be blank");
return false;
}
else if (email==null || email=="")
{
alert("Email can't be blank");
return false;
}
else if (username==null || username=="")
{
alert("Username can't be blank");
return false;
}
else if(password.length<6)
{
alert("Password must be at least 6 characters long.");
return false;
}
else if (password!=conpassword)
{
alert("Confirm Password should match with the Password");
return false;
}
}
</script>
</head>
<body>
<center><h2>Java Registration application using MVC and MySQL </h2></center>
<form name="form" action="RegisterServlet" method="post" onsubmit="return validate()">
<table align="center">
<tr>
<td>Full Name</td>
<td><input type="text" name="fullname" /></td>
</tr>
<tr>
<td>Email</td>
<td><input type="text" name="email" /></td>
</tr>
<tr>
<td>Username</td>
<td><input type="text" name="username" /></td>
</tr>
<tr>
<td>Password</td>
<td><input type="password" name="password" /></td>
</tr>
<tr>
<td>Confirm Password</td>
<td><input type="password" name="conpassword" /></td>
</tr>
<tr>
<td><%=(request.getAttribute("errMessage") == null) ? ""
: request.getAttribute("errMessage")%></td>
</tr>
<tr>
<td></td>
<td><input type="submit" value="Register"></input><input
type="reset" value="Reset"></input></td>
</tr>
</table>
</form>
</body>
</html>
RegisterServlet.java
package com.mvc.controller;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.mvc.bean.RegisterBean;
import com.mvc.dao.RegisterDao;
public class RegisterServlet extends HttpServlet {
public RegisterServlet() {
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//Copying all the input parameters in to local variables
String fullName = request.getParameter("fullname");
String email = request.getParameter("email");
String userName = request.getParameter("username");
String password = request.getParameter("password");
RegisterBean registerBean = new RegisterBean();
//Using Java Beans - An easiest way to play with group of related data
registerBean.setFullName(fullName);
registerBean.setEmail(email);
registerBean.setUserName(userName);
registerBean.setPassword(password);
RegisterDao registerDao = new RegisterDao();
//The core Logic of the Registration application is present here. We are going to insert user data in to the database.
String userRegistered = registerDao.registerUser(registerBean);
if(userRegistered.equals("SUCCESS")) //On success, you can display a message to user on Home page
{
request.getRequestDispatcher("/Home.jsp").forward(request, response);
}
else //On Failure, display a meaningful message to the User.
{
request.setAttribute("errMessage", userRegistered);
request.getRequestDispatcher("/Register.jsp").forward(request, response);
}
}
}
To summarize RegisterServlet.java flow :
1. Assign all the inputs(user details) to local variables.
2. Call RegisterBean.java to set all the user details using java setters.
3. Next, go to RegisterDao.java where you are just going to insert user details into the database.
4. Once it is successful, you are displaying a successful message.
RegisterDao.java
Data Access Object – It focuses on business logic with database connections and operations.
Here the RegisterDao.java code makes a connection with the Database layer and inserts user details into the database.
package com.mvc.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import com.mvc.bean.RegisterBean;
import com.mvc.util.DBConnection;
public class RegisterDao {
public String registerUser(RegisterBean registerBean)
{
String fullName = registerBean.getFullName();
String email = registerBean.getEmail();
String userName = registerBean.getUserName();
String password = registerBean.getPassword();
Connection con = null;
PreparedStatement preparedStatement = null;
try
{
con = DBConnection.createConnection();
String query = "insert into users(SlNo,fullName,Email,userName,password) values (NULL,?,?,?,?)"; //Insert user details into the table 'USERS'
preparedStatement = con.prepareStatement(query); //Making use of prepared statements here to insert bunch of data
preparedStatement.setString(1, fullName);
preparedStatement.setString(2, email);
preparedStatement.setString(3, userName);
preparedStatement.setString(4, password);
int i= preparedStatement.executeUpdate();
if (i!=0) //Just to ensure data has been inserted into the database
return "SUCCESS";
}
catch(SQLException e)
{
e.printStackTrace();
}
return "Oops.. Something went wrong there..!"; // On failure, send a message from here.
}
}
RegisterBean.java
JavaBeans are classes that encapsulate many objects into a single object (the bean). A JavaBean property is a named feature that can be accessed by the user of the object. Here the RegisterBean encapsulates registration properties fullName, email, userName, password. To set or access individual properties, set and get functions have been implemented.
package com.mvc.bean;
public class RegisterBean {
private String fullName;
private String email;
private String userName;
private String password;
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public void setFullName(String fullName) {
this.fullName = fullName;
}
public String getFullName() {
return fullName;
}
public void setEmail(String email) {
this.email = email;
}
public String getEmail() {
return email;
}
}
DBConnection.java We are making use of MySQL database server in this application. The URL format and driver name going to be different for different database servers.
package com.mvc.util;
import java.sql.Connection;
import java.sql.DriverManager;
public class DBConnection {
public static Connection createConnection()
{
Connection con = null;
String url = "jdbc:mysql://localhost:3306/customers"; //MySQL URL followed by the database name
String username = "root"; //MySQL username
String password = "root123"; //MySQL password
System.out.println("In DBConnection.java class ");
try
{
try
{
Class.forName("com.mysql.jdbc.Driver"); //loading MySQL drivers. This differs for database servers
}
catch (ClassNotFoundException e)
{
e.printStackTrace();
}
con = DriverManager.getConnection(url, username, password); //attempting to connect to MySQL database
System.out.println("Printing connection object "+con);
}
catch (Exception e)
{
e.printStackTrace();
}
return con;
}
}
web.xml
The web.xml is known as the deployment descriptor. It declares which Servlets exist and which URLs they handle. You need to mention the fully qualified path for Servlet here.
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>RegistrationMVC</display-name>
<welcome-file-list>
<welcome-file>Register.jsp</welcome-file>
</welcome-file-list>
<servlet>
<description></description>
<display-name>RegisterServlet</display-name>
<servlet-name>RegisterServlet</servlet-name>
<servlet-class>com.mvc.controller.RegisterServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>RegisterServlet</servlet-name>
<url-pattern>/RegisterServlet</url-pattern>
</servlet-mapping>
</web-app>
Home.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Home Page</title>
</head>
<body>
<center><h2>Home Page</h2></center>
<b>User Registration Successful</b>
<br></br>
<b>Please <a href="https://krazytech.com/programs/a-login-application-in-java-using-model-view-controllermvc-design-pattern">log-in</a> to continue.</b>
</body>
</html>
The code base can be downloaded from here.
HTTP Status 500 –
type Exception report
message
description The server encountered an internal error that prevented it from fulfilling this request.
exception
java.lang.NullPointerException
com.mvc.dao.RegisterDao.registerUser(RegisterDao.java:23)
com.mvc.controller.RegisterServlet.doPost(RegisterServlet.java:38)
javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
note The full stack trace of the root cause is available in the Apache Tomcat/8.0.44 logs.
i am phasing this error when clicking the register button plz help me out to solve this
Hi,
I have analyzed the issue. The issue is mainly because of using the higher version of MySQL server.
The Mysql connection string and driver details need to be updated if you are using MySQL version 5+. If not, the same code will work.
Please find the source code and try it yourself – https://krazytech.com/wp-content/uploads/2020/07/RegistrationMvc.zip
HTTP Status 500 -Internal Server Error
java.lang.NullPointerException
com.mvc.dao.RegisterDao.registerUser(RegisterDao.java:21)
com.mvc.controller.RegisterServlet.doPost(RegisterServlet.java:33)
javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
Hi sir, i am up with this kind of error plz help me ….
Hi Smruti,
Have you maintained the same directory structure and file names? Did you include web.xml and jar files?
HTTP Status 404 – Not Found
Type Status Report
Message /RegisterMVC/RegisterServlet
Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.
help me i got this error
Hi,
Check on 2 things.
1. Directory structure and names of each file.
2. Match web.xml as per names used.
Kindly tell me how the video file can be uploaded by admin
and display on website.
sir ,many of them not only me suffering with HTTP Status 500 -Internal Server Error
java.lang.NullPointerException
com.mvc.dao.RegisterDao.registerUser(RegisterDao.java:21)
com.mvc.controller.RegisterServlet.doPost(RegisterServlet.java:33)
javax.servlet.http.HttpServlet.service(HttpServlet.java:647)
javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) error
plse help sir
Hi Charan,
As I have mentioned many times, this is because of the MySQL database version. You can take the following source code and try to compile it.
https://krazytech.com/wp-content/uploads/2020/07/RegistrationMvc.zip
Let me know if this works or not
i checked that 02 things and it was showing like this only.
HTTP Status 404 – Not Found
Type Status Report
Message /RegisterMVC/RegisterServlet
Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.
help me i got this error
Hi,
Did you download the source code and try? It is a working example that I have uploaded.
The origin server did not find a current representation for the target resource – 404 means file not found.
/RegisterMVC/RegisterServlet – Check whether the servlet name and the directory name are exactly matching.
Also, can you explain me at what point are you getting this error?