Step-by-step tutorial to get you started with Spring Boot

Spring Boot is an open-source, opinionated framework built on top of the Spring Framework, designed to simplify and accelerate the development of production-ready, stand-alone, and enterprise-grade applications. It provides a set of features and conventions that enable developers to quickly set up, configure, and deploy applications with minimal boilerplate code.

Key features of Spring Boot include:

  1. Auto-Configuration: Spring Boot automatically configures the application based on classpath dependencies and sensible defaults. It intelligently sets up various components like databases, web servers, security, etc., based on the libraries you include in your project.
  2. Standalone Applications: Spring Boot applications are self-contained and can be run without deploying them in a traditional application server. They embed an embedded web server (e.g., Tomcat, Jetty, or Undertow), making it easy to package and execute applications as executable JAR files.
  3. Spring Boot Starters: Starters are opinionated, pre-configured dependencies that simplify the inclusion of common functionality. For instance, the "Spring Web" starter includes everything needed to build a web application, such as web, REST, and Tomcat support.
  4. Actuator: Spring Boot Actuator provides production-ready features to monitor and manage the application. It exposes endpoints for health checks, metrics, tracing, logging, and more, making it easier to gain insights into the application's behavior in a production environment.
  5. Spring Boot DevTools: DevTools offer several development-time features like automatic application restart, live reload, and remote debugging. These tools significantly enhance the development experience.
  6. Simplified Configuration: Spring Boot utilizes sensible defaults and a property-based configuration mechanism. Configuration files can be written in various formats like properties, YAML, or JSON, making it easier to manage application settings.
  7. Spring Data JPA Integration: Spring Boot smoothly integrates with Spring Data JPA, simplifying database access through easy-to-use repositories and eliminating the need for boilerplate data access code.
  8. Embedded Database Support: Spring Boot includes support for embedded in-memory databases (e.g., H2, HSQLDB) that facilitate fast development and testing without requiring an external database setup.
  9. Production-Ready Defaults: Spring Boot emphasizes best practices for production-ready applications, including default security settings, optimized performance, and sensible logging configurations.
  10. Externalized Configuration: Spring Boot enables you to externalize configuration, allowing properties to be easily overridden or supplied through various sources like environment variables, system properties, or configuration files.
  11. Support for Various Architectures: Spring Boot supports a variety of architectural styles, including monoliths, microservices, and serverless applications, allowing developers to choose the most suitable approach for their projects.

Overall, Spring Boot is an excellent choice for developers looking to build robust and scalable applications with minimal configuration overhead. Its opinionated nature and built-in conventions speed up development and make it a popular framework for a wide range of applications.

Step-by-Step tutorial on spring boot as below

Prerequisites:
  • Basic knowledge of Java programming language.
  • Familiarity with RESTful API concepts.

Step 1: Set Up Your Development Environment

  1. Install Java: Make sure you have Java 8 or higher installed on your machine.
  2. Install an Integrated Development Environment (IDE): Popular choices include Eclipse, IntelliJ IDEA, or Visual Studio Code.
  3. Install Apache Maven: Maven is a build automation tool for Java projects and is used by Spring Boot. Download and install Maven from the official website.

Step 2: Create a New Spring Boot Project

  1. Open your IDE and create a new Spring Boot project.
  2. Choose the "Spring Initializr" or "New Project" option and select "Maven Project."
  3. Set up the project with the following options:
    • Group: com.example
    • Artifact: task-manager
    • Dependencies: Select "Spring Web," "Spring Security," "Spring Data MongoDB," "Thymeleaf" (for simplicity), and any other dependencies you might need.
    • Click "Finish" to create the project. This will generate a basic Spring Boot project structure.

Step 3: Configure MongoDB Connection

  1. Open the application.properties file (or application.yml if using YAML configuration) in the src/main/resources folder.
  2. Configure the MongoDB connection properties:
      
    spring.data.mongodb.host=localhost
    spring.data.mongodb.port=27017
    spring.data.mongodb.database=my_database
    
    Replace the values with your MongoDB connection details.

Step 4: Create the User and Task Entities

  1. Create a new package named com.example.model in the src/main/java folder.
  2. Inside the model package, create a new Java class named User:
      
    package com.example.model;
    
    import org.springframework.data.annotation.Id;
    import org.springframework.data.mongodb.core.mapping.Document;
    
    @Document(collection = "users")
    public class User {
        @Id
        private String id;
        private String username;
        private String password;
    
        // Constructors, getters, setters, and other methods
    }
    
    Create another Java class named Task:
      
    package com.example.model;
    
    import org.springframework.data.annotation.Id;
    import org.springframework.data.mongodb.core.mapping.Document;
    
    @Document(collection = "tasks")
    public class Task {
        @Id
        private String id;
        private String name;
        private boolean completed;
    
        // Constructors, getters, setters, and other methods
    }
    

Step 5: Create the User Repository

Create a new package named com.example.repository in the src/main/java folder. Inside the repository package, create a new Java interface named UserRepository:
  
package com.example.repository;

import com.example.model.User;
import org.springframework.data.mongodb.repository.MongoRepository;

public interface UserRepository extends MongoRepository {
    User findByUsername(String username);
}

Step 6: Implement User Authentication and Authorization

Create a new package named com.example.security in the src/main/java folder. Inside the security package, create a new Java class named SecurityConfig:
  
package com.example.security;

import com.example.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.crypto.password.PasswordEncoder;

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    private final UserRepository userRepository;
    private final PasswordEncoder passwordEncoder;

    @Autowired
    public SecurityConfig(UserRepository userRepository, PasswordEncoder passwordEncoder) {
        this.userRepository = userRepository;
        this.passwordEncoder = passwordEncoder;
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(username -> userRepository.findByUsername(username))
            .passwordEncoder(passwordEncoder);
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            .authorizeRequests()
                .antMatchers("/register").permitAll()
                .anyRequest().authenticated()
                .and()
            .formLogin()
                .loginPage("/login")
                .permitAll()
                .and()
            .logout()
                .permitAll();
    }
}

Step 7: Create User Registration and Login Views

Inside the src/main/resources/templates folder, create a new Thymeleaf HTML file named register.html for user registration:
  
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="UTF-8">
<title>Task Manager - Register</title>
</head>
<body>
<h1>Register</h1>
    <form action="/register" method="post">
        <label for="username">Username:</label>
        <input type="text" id="username" name="username" required>
        <br>
        <label for="password">Password:</label>
        <input type="password" id="password" name="password" required>
        <br>
        <button type="submit">Register</button>
    </form>
</body>
</html>
Create another Thymeleaf HTML file named login.html for user login:
  
  <!DOCTYPE html>
  <html lang="en" xmlns:th="http://www.thymeleaf.org">
  <head>
      <meta charset="UTF-8">
      <title>Task Manager - Login</title>
  </head>
<body>
<h1>Login</h1>
<form action="/login" method="post">
<label for="username">Username:</label>
<input type="text" id="username" name="username" required>
<br>
<label for="password">Password:</label>
<input type="password" id="password" name="password" required>
<br>
<button type="submit">Login</button>
</form>
</body>
</html>

Step 8: Implement User Registration and Login Controllers

Create a new package named com.example.controller in the src/main/java folder. Inside the controller package, create a new Java class named UserController:
  
package com.example.controller;

import com.example.model.User;
import com.example.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;

@Controller
public class UserController {
    private final UserRepository userRepository;
    private final PasswordEncoder passwordEncoder;

    @Autowired
    public UserController(UserRepository userRepository, PasswordEncoder passwordEncoder) {
        this.userRepository = userRepository;
        this.passwordEncoder = passwordEncoder;
    }

    @GetMapping("/register")
    public String showRegistrationForm() {
        return "register";
    }

    @PostMapping("/register")
    public String registerUser(@RequestParam String username, @RequestParam String password) {
        User user = new User();
        user.setUsername(username);
        user.setPassword(passwordEncoder.encode(password));
        userRepository.save(user);
        return "redirect:/login";
    }

    @GetMapping("/login")
    public String showLoginForm() {
        return "login";
    }
}

Step 9: Create the Task Service

Create a new package named com.example.service in the src/main/java folder. Inside the service package, create a new Java class named TaskService:
  
package com.example.service;

import com.example.model.Task;
import com.example.repository.TaskRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;
import java.util.Optional;

@Service
public class TaskService {
    private final TaskRepository taskRepository;

    @Autowired
    public TaskService(TaskRepository taskRepository) {
        this.taskRepository = taskRepository;
    }

    public List<Task> getAllTasks() {
        return taskRepository.findAll();
    }

    public Optional<Task> getTaskById(String id) {
        return taskRepository.findById(id);
    }

    public Task saveTask(Task task) {
        return taskRepository.save(task);
    }

    public void deleteTaskById(String id) {
        taskRepository.deleteById(id);
    }
}

Step 10: Implement the Task Controller

Create a new package named com.example.controller in the src/main/java folder (if not already created). Inside the controller package, modify the existing TaskController class to include REST API endpoints for tasks:
  
package com.example.controller;

import com.example.model.Task;
import com.example.service.TaskService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;

import java.util.List;
import java.util.Optional;

@RestController
@RequestMapping("/tasks")
public class TaskController {
    private final TaskService taskService;

    @Autowired
    public TaskController(TaskService taskService) {
        this.taskService = taskService;
    }

    @GetMapping
    public List<Task> getAllTasks() {
        return taskService.getAllTasks();
    }

    @GetMapping("/{id}")
    public ResponseEntity<Task> getTaskById(@PathVariable String id) {
        Optional<Task> task = taskService.getTaskById(id);
        return task.map(ResponseEntity::ok).orElse(ResponseEntity.notFound().build());
    }

    @PostMapping
    public Task createTask(@RequestBody Task task) {
        return taskService.saveTask(task);
    }

    @PutMapping("/{id}")
    public ResponseEntity<Task> updateTask(@PathVariable String id, @RequestBody Task updatedTask) {
        Optional<Task> task = taskService.getTaskById(id);
        if (task.isPresent()) {
            Task taskToUpdate = task.get();
            taskToUpdate.setName(updatedTask.getName());
            taskToUpdate.setCompleted(updatedTask.isCompleted());
            return ResponseEntity.ok(taskService.saveTask(taskToUpdate));
        } else {
            return ResponseEntity.notFound().build();
        }
    }

    @DeleteMapping("/{id}")
    public ResponseEntity<Void> deleteTask(@PathVariable String id) {
        Optional<Task> task = taskService.getTaskById(id);
        if (task.isPresent()) {
            taskService.deleteTaskById(id);
            return ResponseEntity.noContent().build();
        } else {
            return ResponseEntity.notFound().build();
        }
    }
}

Step 11: Run the Application

Open a terminal and navigate to the root directory of your Spring Boot project. Build and run the application using Maven:
  
mvn spring-boot:run

Step 12: Test the Application

Access the application in your web browser: http://localhost:8080/register Register a new user. Log in with the registered user: http://localhost:8080/login After logging in, you should be redirected to the task manager page, where you can manage tasks. You can also test the REST API endpoints using tools like curl, Postman, or a web browser extension. The API endpoints are the same as mentioned in Step 8.

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