Example of Blog Screen Structure and Adding Edit/Create Features

Spring Boot is a Java-based framework that is very popular for backend development of web applications these days. In this course, we will explain the process of developing a simple blog system using Spring Boot step by step. In particular, we will cover in detail examples of blog screen structure and features for editing and creating posts.

1. Starting the Project

First, we use Spring Initializr to start a Spring Boot project. Visit Spring Initializr and set it up as follows:

• Project: Maven Project
• Language: Java
• Spring Boot: 2.5.4 (Select the latest version)
• Packaging: Jar
• Java Version: 11
• Dependencies: Spring Web, Spring Data JPA, H2 Database, Spring Boot DevTools

Once the setup is complete, click the ‘GENERATE’ button to download the project. Unzip the downloaded ZIP file and open the project in your IDE (e.g., IntelliJ IDEA or Eclipse).

2. Creating a Blog Post Entity Model

We define the Post model for the blog we are going to create. To do this, we create a class named `Post` and use JPA annotations to define the structure of the database.

java
@Entity
public class Post {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String title;
    private String content;
    private LocalDateTime createdAt;

    // getter, setter...
}
        

Each field in the Post class you created should have appropriate annotations to grant it the properties of a JPA entity.

3. Creating the Repository

Now, we need to create a repository interface that can handle the `Post` entity. Using JPA, CRUD operations can be easily managed.

java
@Repository
public interface PostRepository extends JpaRepository {
    List findAll();
    Optional findById(Long id);
}
        

4. Setting Up the Service Layer

Later, we will write a service class to handle business logic. The service class will rely on dependency injection from the repository to provide CRUD functionality.

java
@Service
public class PostService {
    private final PostRepository postRepository;

    @Autowired
    public PostService(PostRepository postRepository) {
        this.postRepository = postRepository;
    }

    public List getAllPosts() {
        return postRepository.findAll();
    }

    public Post getPostById(Long id) {
        return postRepository.findById(id).orElse(null);
    }

    public Post createPost(Post post) {
        return postRepository.save(post);
    }

    public Post updatePost(Long id, Post postDetails) {
        Post post = getPostById(id);
        if (post != null) {
            post.setTitle(postDetails.getTitle());
            post.setContent(postDetails.getContent());
            return postRepository.save(post);
        }
        return null;
    }

    public void deletePost(Long id) {
        postRepository.deleteById(id);
    }
}
        

5. Setting Up the Controller

Create a controller class that provides a RESTful API to communicate with the frontend. You can use `@RestController` to handle HTTP requests.

java
@RestController
@RequestMapping("/api/posts")
public class PostController {
    private final PostService postService;

    @Autowired
    public PostController(PostService postService) {
        this.postService = postService;
    }

    @GetMapping
    public List getAllPosts() {
        return postService.getAllPosts();
    }

    @GetMapping("/{id}")
    public Post getPost(@PathVariable Long id) {
        return postService.getPostById(id);
    }

    @PostMapping
    public Post createPost(@RequestBody Post post) {
        return postService.createPost(post);
    }

    @PutMapping("/{id}")
    public Post updatePost(@PathVariable Long id, @RequestBody Post post) {
        return postService.updatePost(id, post);
    }

    @DeleteMapping("/{id}")
    public ResponseEntity deletePost(@PathVariable Long id) {
        postService.deletePost(id);
        return ResponseEntity.noContent().build();
    }
}
        

6. Setting Up the H2 Database

We will set up the H2 database for easy use during the development process. Configure it in the `application.properties` file as follows:

properties
spring.h2.console.enabled=true
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=password
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
        

To access the H2 database console, you can use the path /h2-console.

7. Setting Up the Blog Screen

Implement the screen that makes up the blog using HTML and CSS. For example, prepare a detailed page to display the list of posts and each post.

html




    
    


    
Blog Post List
    

    


        

8. Adding Edit/Create Functionality

We will add features that allow users to create and edit blog posts. To do this, we need to implement an HTML form to receive user input.

html

    
    
    Create Post


        

With this code, users can create a new blog post by entering a title and content. Additionally, similar functionality can be implemented to edit existing posts.

9. Conclusion

In this course, we learned how to build a simple blog system using Spring Boot. Through database setup, RESTful API configuration, HTML screen implementation, and adding post creation/editing features, we have gained an understanding of the basics of web applications. Based on this, consider adding more complex features or expanding the project while considering long-term compatibility with other frameworks.

Thank you! I hope your journey in Spring Boot backend development is successful.