Cara menggunakan Java untuk membangunkan fungsi pengurusan sumber sistem CMS

- src/main/java/
  - com.example.cms/
    - controller/
    - model/
    - repository/
    - service/
- src/main/resources/
  - application.properties
- pom.xml

<!-- Spring Boot -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

<!-- Spring Data JPA -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>

<!-- MySQL Connector -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>

<!-- Apache Commons FileUpload -->
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.4</version>
</dependency>

@Entity
@Table(name = "resources")
public class Resource {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false)
    private String filename;

    // Getters and setters
}

@Repository
public interface ResourceRepository extends JpaRepository<Resource, Long> {
}

@RestController
public class ResourceController {
    private static final String UPLOAD_DIR = "uploads/";

    @Autowired
    private ResourceRepository resourceRepository;

    @PostMapping("/resources")
    public ResponseEntity<String> upload(@RequestParam("file") MultipartFile file) {
        try {
            String filename = file.getOriginalFilename();
            String filePath = UPLOAD_DIR + filename;
            Path path = Paths.get(filePath);

            Files.write(path, file.getBytes());

            Resource resource = new Resource();
            resource.setFilename(filename);
            resourceRepository.save(resource);

            return ResponseEntity.ok().body("File uploaded successfully.");
        } catch (IOException e) {
            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("Error uploading file.");
        }
    }
}

@RestController
public class ResourceController {
    // ...

    @GetMapping("/resources/{id}")
    public ResponseEntity<Resource> download(@PathVariable("id") Long id) {
        Optional<Resource> optionalResource = resourceRepository.findById(id);

        if (optionalResource.isPresent()) {
            Resource resource = optionalResource.get();
            String filePath = UPLOAD_DIR + resource.getFilename();
            Path path = Paths.get(filePath);

            if (Files.exists(path)) {
                Resource file = new UrlResource(path.toUri());
                return ResponseEntity.ok()
                        .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename="" + file.getFilename() + """)
                        .body(file);
            }
        }

        return ResponseEntity.notFound().build();
    }
}

@RestController
public class ResourceController {
    // ...

    @DeleteMapping("/resources/{id}")
    public ResponseEntity<String> delete(@PathVariable("id") Long id) {
        Optional<Resource> optionalResource = resourceRepository.findById(id);

        if (optionalResource.isPresent()) {
            Resource resource = optionalResource.get();
            String filePath = UPLOAD_DIR + resource.getFilename();
            Path path = Paths.get(filePath);

            try {
                Files.deleteIfExists(path);
                resourceRepository.delete(resource);

                return ResponseEntity.ok().body("Resource deleted successfully.");
            } catch (IOException e) {
                return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("Error deleting resource.");
            }
        }

        return ResponseEntity.notFound().build();
    }
}