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.
Hello Sir,
I am facing this problem can u help me out
Exception
java.lang.NullPointerException
com.mvc.dao.RegisterDao.registerUser(RegisterDao.java:23)
com.mvc.controller.RegisterServlet.doPost(RegisterServlet.java:33)
javax.servlet.http.HttpServlet.service(HttpServlet.java:652)
javax.servlet.http.HttpServlet.service(HttpServlet.java:733)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
Hello Godavari,
The issue could be because of MySQL version. The latest version has some driver related changes.
Can you please try with the following code once?
https://krazytech.com/wp-content/uploads/2020/07/RegistrationMvc.zip
Hi Ravi,
/*
I am getting this below error:
In DB Connection Succesfully
SQL connected succesfullycom.mysql.cj.jdbc.ConnectionImpl@7191eda3
java.sql.SQLIntegrityConstraintViolationException: Column ‘fullName’ cannot be null
*/
I have given all the columns to be not null in mysql and while filling the form I have given all the values but still it isnt inserting into the database.
Any idea what the issue might be.
I have tried multiple ways but cant find any solution
Below is my query
String query = “insert into login_users(fullName,emailId,mobileNo,Age,UserName,Password) Values(?,?,?,?,?,?)”
Hi Pavani,
Before inserting into the database, print all the values and check if anything is going null.
I think you are missing out the serial number column which will be an auto incrementing unique key. Refer to my database script.
Also, make use of MySQL query window to run your query along with the values to debug it.
“insert into users(SlNo,fullName,Email,userName,password) values (NULL,?,?,?,?)”;
Glad to see that you are modifying the application as per your needs. Keep learning!
hi, i’m getting this problem, can u help me?
HTTP Status 500 – Internal Server Error
type Exception report
messageInternal Server Error
descriptionThe server encountered an internal error that prevented it from fulfilling this request.
exception
java.lang.NullPointerException
note The full stack traces of the exception and its root causes are available in the GlassFish Server Open Source Edition 4.1.1 logs.
Hi,
It is mainly happening because of MySQL version. I have attached the full project over here. Please try it.
https://krazytech.com/wp-content/uploads/2020/07/RegistrationMvc.zip
Hi ,
I have got the same error and I tried to change the JDBC driver. If your mysql version is 8.0 get the latest version of jdbc driver online on their website and import it under lib section in eclipse. It will be working now.
Regards,
Pavani
Thanks for helping Syahirah, Pavani.