Spring MVC Login Application

Technology Stack

Project Structure

Table of Contents

pom.xml

Add the below in pom.xml

spring-boot-starter-parent – add this as parent
mysql-connector-java – needed for mysql driver and other related classes.

Add the below spring boot starters

spring-boot-starter-web – needed for spring mvc
spring-boot-starter-thymeleaf – needed for thymeleaf
spring-boot-starter-data-jpa – needed for spring data jpa

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-parent</artifactId>

<version>2.2.2.RELEASE</version>

</parent>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-web</artifactId>

</dependency>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-thymeleaf</artifactId>

</dependency>

<groupId>mysql</groupId>

<artifactId>mysql-connector-java</artifactId>

</dependency>

<groupId>org.springframework.boot</groupId>

<artifactId>spring-boot-starter-data-jpa</artifactId>

</dependency>

</dependencies>

Domain Layer

Define the Account Entity here.

package com.spring.mvc.model;

import javax.persistence.Entity;

import javax.persistence.Id;

@Entity

public class Account {

public Account() {}

@Id

private String username;

public Account(String username, String password, String firstname, String lastname) {

this.username = username;

this.password = password;

this.firstname = firstname;

this.lastname = lastname;

}

private String password;

private String firstname;

private String lastname;

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 String getFirstname() {

return firstname;

}

public void setFirstname(String firstname) {

this.firstname = firstname;

}

public String getLastname() {

return lastname;

}

public void setLastname(String lastname) {

this.lastname = lastname;

}

Repository Layer

Define the Spring Data JPA Interface which extends CrudRepository.

Please visit Spring Data JPA+Spring Boot+MySQL for better understanding of Spring Data JPA.

package com.spring.mvc.repository;

import org.springframework.data.repository.CrudRepository;

import com.spring.mvc.model.Account;

public interface AccountRepository extends CrudRepository<Account, String>{

}

Service Layer

Define Service Interface

package com.spring.mvc.service;

import com.spring.mvc.model.Account;

public interface AccountService {

public Account createAccount(Account account);

public Account findAccount(String username, String password);

}

Define Service Implementation

package com.spring.mvc.service;

import java.util.Optional;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import com.spring.mvc.model.Account;

import com.spring.mvc.repository.AccountRepository;

@Service

public class AccountServiceImpl implements AccountService{

@Autowired

private AccountRepository repository;

@Override

public Account createAccount(Account account) {

if (repository.existsById(account.getUsername())) {

return null;

}

return repository.save(account);

}

@Override

public Account findAccount(String username, String password) {

Optional<Account> dbAccount = repository.findById(username);

if (dbAccount.isPresent() && dbAccount.get().getPassword().equals(password)) {

return dbAccount.get();

}

return null;

}

Controller Layer

package com.spring.mvc.controller;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Controller;

import org.springframework.ui.Model;

import org.springframework.util.StringUtils;

import org.springframework.web.bind.annotation.GetMapping;

import org.springframework.web.bind.annotation.PostMapping;

import org.springframework.web.bind.annotation.RequestParam;

import com.spring.mvc.model.Account;

import com.spring.mvc.service.AccountService;

@Controller

public class ApplicationController {

@Autowired

private AccountService accountService;

@GetMapping(“/”)

public String landingPage(Model model) {

return “landing”;

}

@PostMapping(“/login”)

public String welcome(@RequestParam(“username”) String username, @RequestParam(“password”) String password,

Model model) {

if(username == null || username.isEmpty()) {

model.addAttribute(“errormessage”, “Please enter username”);

return landingPage(model);

}

if(password == null || password.isEmpty()) {

model.addAttribute(“password”, “Please enter password”);

return landingPage(model);

}

Account account = accountService.findAccount(username, password);

if (account == null) {

model.addAttribute(“errormessage”, “Your username and password combination is not correct”);

model.addAttribute(“username”, username);

model.addAttribute(“password”, password);

return landingPage(model);

}

model.addAttribute(“account”, account);

return “welcome”;

}

@GetMapping(“/registration”)

public String registration(Model model) {

return “registration”;

}

@PostMapping(“/createAccount”)

public String createAccount(Model model,@RequestParam(“username”) String username,

@RequestParam(“password”) String password,@RequestParam(“againpassword”) String againpassword,

@RequestParam(“firstname”) String firstname,@RequestParam(“lastname”) String lastname) {

boolean reloadPage = false;

if (StringUtils.isEmpty(username) || StringUtils.isEmpty(password) || StringUtils.isEmpty(againpassword)

|| StringUtils.isEmpty(firstname) || StringUtils.isEmpty(lastname)) {

reloadPage = true;

model.addAttribute(“errormessage”, “All fields are mandatory.”);

}

if (!reloadPage && !password.equals(againpassword)) {

reloadPage = true;

model.addAttribute(“errormessage”, “Password does not match”);

}

if (!reloadPage) {

Account account = new Account(username, password, firstname, lastname);

Account dbAccount = accountService.createAccount(account);

if (dbAccount == null) {

reloadPage = true;

model.addAttribute(“errormessage”, “Account already exists for the username”);

}

if (reloadPage) {

model.addAttribute(“username”, username);

model.addAttribute(“password”, password);

model.addAttribute(“againpassword”, againpassword);

model.addAttribute(“firstname”, firstname);

model.addAttribute(“lastname”, lastname);

return registration(model);

}

model.addAttribute(“message”, “Account successfully created. Please login.”);

return landingPage(model);

}

Application class annotated with @SpringBootApplication

Define datasource, entityManagerFactory and other beans here.

package com.spring.mvc.config;

import java.util.Properties;

import javax.sql.DataSource;

import org.hibernate.jpa.HibernatePersistenceProvider;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.PropertySource;

import org.springframework.core.env.Environment;

import org.springframework.data.jpa.repository.config.EnableJpaRepositories;

import org.springframework.jdbc.datasource.DriverManagerDataSource;

import org.springframework.orm.jpa.JpaTransactionManager;

import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;

import org.springframework.transaction.annotation.EnableTransactionManagement;

@SpringBootApplication(scanBasePackages = {“com.spring.mvc.controller”,”com.spring.mvc.service”})

@EnableTransactionManagement

@EnableJpaRepositories(“com.spring.mvc.repository”)

@PropertySource(“classpath:database.properties”)

public class Application {

public static void main(String[] args) {

SpringApplication.run(Application.class, args);

}

@Autowired

Environment environment;

private final String URL = “url”;

private final String USER = “dbuser”;

private final String PASSWORD = “dbpassword”;

private final String PROPERTY_SHOW_SQL = “hibernate.show_sql”;

private final String PROPERTY_DIALECT = “hibernate.dialect”;

@Bean

DataSource dataSource() {

DriverManagerDataSource driverManagerDataSource = new DriverManagerDataSource();

driverManagerDataSource.setUrl(environment.getProperty(URL));

driverManagerDataSource.setUsername(environment.getProperty(USER));

driverManagerDataSource.setPassword(environment.getProperty(PASSWORD));

return driverManagerDataSource;

}

@Bean

LocalContainerEntityManagerFactoryBean entityManagerFactory() {

LocalContainerEntityManagerFactoryBean lfb = new LocalContainerEntityManagerFactoryBean();

lfb.setDataSource(dataSource());

lfb.setPersistenceProviderClass(HibernatePersistenceProvider.class);

lfb.setPackagesToScan(“com.spring.mvc.model”);

lfb.setJpaProperties(hibernateProps());

return lfb;

}

Properties hibernateProps() {

Properties properties = new Properties();

properties.setProperty(PROPERTY_DIALECT, environment.getProperty(PROPERTY_DIALECT));

properties.setProperty(PROPERTY_SHOW_SQL, environment.getProperty(PROPERTY_SHOW_SQL));

return properties;

}

@Bean

JpaTransactionManager transactionManager() {

JpaTransactionManager transactionManager = new JpaTransactionManager();

transactionManager.setEntityManagerFactory(entityManagerFactory().getObject());

return transactionManager;

}

database.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/testchema
dbuser=root
dbpassword=root
hibernate.dialect=org.hibernate.dialect.MySQLDialect
hibernate.show_sql=true

View Layer – templates

Thymeleaf is a default template used by Spring Boot.
By default, Spring Boot looks for the templates in src/main/resources/templates location.

Add the html files inside src/main/resources/templates

landing.html

<head>
<meta http-equiv=”Content-Type” content=”text/html; charset=UTF-8″>
<title>Application</title>
<link rel=”stylesheet” href=″https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css″>

</head>
<body style=”width:50%;margin: 20px;padding: 20px;”>
<h3>Spring MVC Application using Spring Boot and Thymeleaf</h3>
<p style=”color: red;”>[[${errormessage}]]</p>
<p style=”color: green;”>[[${message}]]</p>
<div style=”margin: 20px;border: 1px solid blue;padding: 20px;”>
<div class=”form” style=”margin: 20px;padding: 20px;”>
<h4>Login</h4>
<form action=”login” method=”post”>
<table class=”table table-bordered”>
<tr>
<td>Please Enter Your UserName</td>
<td><input id=”username” name=”username” th:value=”${username}”></td>
</tr>
<tr>
<td>Please Enter Your Password</td>
<td><input id=”password” name=”password” type=”password” th:value=”${password}”></td>
</tr>
</table>
<input type=”submit” value=”Submit”>
</form>
</div>

welcome.html

</head>
<body style=”width:50%;”>
<div style=”margin: 20px;padding: 20px;”>
<h3>Spring MVC Application using Spring Boot and Thymeleaf</h3>
<div class=”form” style=”margin: 20px;border: 1px solid blue;padding: 20px;”>

<h4>Your Details are mentioned below:</h4>
<table class=”table table-bordered” style=”padding: 20px;”>
<tr>
<td>UserName</td>
<td>[[${account.username}]]</td>
</tr>
<tr>
<td>FirstName</td>
<td>[[${account.firstname}]]</td>
</tr>
<tr>
<td>LastName</td>
<td>[[${account.lastname}]]</td>
</tr>
</table>
<div class=”form”>
<form action=”/” method=”get”>
<table>
<tr>
<td><input type=”submit” value=”Logout”></td>
</tr>
</table>
</form>
</div>
</div>
</div>
</body>
</html>

registration.html

</head>

</head>

<body style=”width:50%;margin: 20px;padding: 20px;”>
<h3>Spring MVC Application using Spring Boot and Thymeleaf</h3>
<p style=”color: red;”>[[${errormessage}]]</p>
<div style=”margin: 20px;border: 1px solid blue;padding: 20px;”>
<div class=”form” style=”margin: 20px;padding: 20px;”>
<h4>Registration</h4>
<form action=”createAccount” method=”post”>
<table class=”table table-bordered”>
<tr>
<td>Please Enter Your UserName</td>
<td><input id=”username” name=”username” th:value=”${username}”></td>
</tr>
<tr>
<td>Please Enter Your Password</td>
<td><input id=”password” name=”password” type=”password” th:value=”${password}”></td>
</tr>
<tr>
<td>Please Enter Your Password Again</td>
<td><input id=”againpassword” name=”againpassword” type=”password” th:value=”${againpassword}”></td>
</tr>
<tr>
<td>Please Enter Your First Name</td>
<td><input id=”firstname” name=”firstname” th:value=”${firstname}”></td>
</tr>
<tr>
<td>Please Enter Your last Name</td>
<td><input id=”lastname” name=”lastname” th:value=”${lastname}”></td>
</tr>

</table>
<input type=”submit” value=”Submit”>
</form>
</div>
<div class=”form”>
<form action=”/” method=”get”>
<table>
<tr>
<td><input type=”submit” value=”Go to Login”></td>
</tr>
</table>
</form>
</div>
</div>