springboot實(shí)現(xiàn)增刪改查實(shí)例

小億
117
2023-12-29 12:31:35

下面是一個(gè)使用Spring Boot實(shí)現(xiàn)增刪改查的示例代碼:

  1. 首先,創(chuàng)建一個(gè)實(shí)體類(lèi),如User.java:
@Entity
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    private String name;
    private int age;
    private String email;

    // getters and setters
}
  1. 創(chuàng)建一個(gè)Repository接口,如UserRepository.java:
@Repository
public interface UserRepository extends JpaRepository<User, Long> {
}
  1. 創(chuàng)建一個(gè)Service類(lèi),如UserService.java:
@Service
public class UserService {
    private final UserRepository userRepository;

    public UserService(UserRepository userRepository) {
        this.userRepository = userRepository;
    }

    public List<User> getAllUsers() {
        return userRepository.findAll();
    }

    public User getUserById(Long id) {
        return userRepository.findById(id).orElse(null);
    }

    public User createUser(User user) {
        return userRepository.save(user);
    }

    public void deleteUser(Long id) {
        userRepository.deleteById(id);
    }

    public User updateUser(Long id, User user) {
        User existingUser = userRepository.findById(id).orElse(null);
        if (existingUser != null) {
            existingUser.setName(user.getName());
            existingUser.setAge(user.getAge());
            existingUser.setEmail(user.getEmail());
            return userRepository.save(existingUser);
        } else {
            return null;
        }
    }
}
  1. 創(chuàng)建一個(gè)Controller類(lèi),如UserController.java:
@RestController
@RequestMapping("/users")
public class UserController {
    private final UserService userService;

    public UserController(UserService userService) {
        this.userService = userService;
    }

    @GetMapping("/")
    public List<User> getAllUsers() {
        return userService.getAllUsers();
    }

    @GetMapping("/{id}")
    public User getUserById(@PathVariable Long id) {
        return userService.getUserById(id);
    }

    @PostMapping("/")
    public User createUser(@RequestBody User user) {
        return userService.createUser(user);
    }

    @DeleteMapping("/{id}")
    public void deleteUser(@PathVariable Long id) {
        userService.deleteUser(id);
    }

    @PutMapping("/{id}")
    public User updateUser(@PathVariable Long id, @RequestBody User user) {
        return userService.updateUser(id, user);
    }
}
  1. 在Spring Boot應(yīng)用程序的入口類(lèi)上添加注解@SpringBootApplication,并運(yùn)行應(yīng)用程序。

現(xiàn)在,你可以使用以下API來(lái)進(jìn)行增刪改查操作:

  • 獲取所有用戶:GET /users/
  • 獲取指定用戶:GET /users/{id}
  • 創(chuàng)建用戶:POST /users/
  • 刪除用戶:DELETE /users/{id}
  • 更新用戶:PUT /users/{id}

請(qǐng)注意,以上代碼只是一個(gè)示例,你可以根據(jù)具體需求進(jìn)行適當(dāng)?shù)男薷摹?/p>

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