Simply Basics: Spring MVC Login Page

In this post we will see how to create a login page using spring 3. Below two screen shots are the directory structure and the jar files that are necessary for to run the login application.

File: WebContent/index.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>Spring Login Page Example</title>
</head>

<body>
 <a href="forms/loginform.html">Click here for Login Page</a>
</body>

</html>

File: com.ram.form.LoginForm

package com.ram.form;

public class LoginForm {
 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;
 }
 
}

File: WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>

<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>Spring Login Page Example</display-name>

 <servlet>
  <servlet-name>dispatcher</servlet-name>
  <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
 </servlet>

 <servlet-mapping>
  <servlet-name>dispatcher</servlet-name>
  <url-pattern>/forms/*</url-pattern>
 </servlet-mapping>

 <welcome-file-list>
  <welcome-file>index.jsp</welcome-file>
 </welcome-file-list>

</web-app>

File: com.ram.controllers.LoginForm.java

package com.ram.controllers;

import java.util.Map;
import javax.validation.Valid;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.ram.form.LoginForm;

@Controller
@RequestMapping("loginform.html")
public class LoginController {
 @RequestMapping(method = RequestMethod.GET)
 public String showForm(Map model) {
  LoginForm loginForm = new LoginForm();
  model.put("loginForm", loginForm);
  return "loginform";
 }

 @RequestMapping(method = RequestMethod.POST)
 public String processForm(@Valid LoginForm loginForm, BindingResult result,
   Map model) {
  String userName = "Admin";
  String password = "root";
  if (result.hasErrors()) {
   return "loginform";

  }
  loginForm = (LoginForm) model.get("loginForm");
  if (!loginForm.getUserName().equals(userName)
    || !loginForm.getPassword().equals(password)) {
   return "loginerror";
  }
  model.put("loginForm", loginForm);
  return "loginsuccess";
 }
}

File: WEB-INF/dispatcher-servlet.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
 xmlns:context="http://www.springframework.org/schema/context"
 xmlns:mvc="http://www.springframework.org/schema/mvc"
 xsi:schemaLocation="http://www.springframework.org/schema/beans
 http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
 http://www.springframework.org/schema/context
 http://www.springframework.org/schema/context/spring-context-3.0.xsd
 http://www.springframework.org/schema/mvc
 http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">

 <!-- Enable annotation driven controllers, validation etc... -->
 <mvc:annotation-driven />

 <context:component-scan base-package="com.ram.controllers" />

 <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
  <property name="prefix" value="/WEB-INF/views/"/>

  <property name="suffix" value=".jsp"/>
 </bean>

 <bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
  <property name="basename" value="/WEB-INF/messages" />
 </bean>

</beans>

File: WEB-INF/views/loginform.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
 pageEncoding="ISO-8859-1"%>

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>
<title>Spring Login Page</title>
</head>

<body>
 <center>
  <h3>Login Page</h3>

  <form:form action="loginform.html" commandName="loginForm">

   <table>
    <tr>
     <td>User Name: <FONT color="red"><form:errors path="userName" /></FONT></td>
     <td><form:input path="userName" /></td>
    </tr>

    <tr>
     <td>Password: <FONT color="red"><form:errors path="password" /></FONT></td>
     <td><form:password path="password" /></td>
    </tr>

   </table>
   
   <p><input type="submit" value="Submit" />
   </p>

  </form:form>

 </center>

</body>

</html>

File: WEB-INF/views/loginsuccess.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
 pageEncoding="ISO-8859-1"%>

<%@ taglib prefix="core" uri="http://java.sun.com/jsp/jstl/core"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>
<title>Spring Success Page</title>

</head>

<body>

 <center>

  <h4>
   Welcome to the <core:out value="${loginForm.userName}" /> page.
  </h4>

  <p>
   <a href="loginform.html">Back</a>
  </p>
 </center>

</body>

</html>

File: WEB-INF/views/loginerror.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>Spring Error Page</title>
</head>

<body>
 <center>
  <h4 style="color: red">Error page, please go back to login page
   and enter correct credentials</h4>

  <p>
   <a href="loginform.html">Retry</a>
  </p>

 </center>

</body>

</html>

Right click. on the "SpringLoginPageExample directory structure and click on "Run As -> Run on Server". Once the login page appeared, enter the credentials "Admin" and "root" to successfully login. If incorrect credentials are given, then error page will be thrown.

Spring MVC Login Page

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