springboot实现注册功能

实现注册功能需要以下步骤：

1. 创建User实体类

@Entity
@Table(name = "users")
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @Column(nullable = false, unique = true)
    private String username;

    @Column(nullable = false)
    private String password;

    @Column(nullable = false)
    private String email;

    // getters and setters
}

2. 创建UserRepository接口

@Repository
public interface UserRepository extends JpaRepository<User, Long> {

    User findByUsername(String username);

    User findByEmail(String email);
}

3. 创建UserService接口和实现类

public interface UserService {

    User register(User user);
}

@Service
public class UserServiceImpl implements UserService {

    @Autowired
    private UserRepository userRepository;

    @Override
    public User register(User user) {
        if (userRepository.findByUsername(user.getUsername()) != null) {
            throw new RuntimeException("Username already exists");
        }
        if (userRepository.findByEmail(user.getEmail()) != null) {
            throw new RuntimeException("Email already exists");
        }
        return userRepository.save(user);
    }
}

4. 创建UserController类

@RestController
@RequestMapping("/api/users")
public class UserController {

    @Autowired
    private UserService userService;

    @PostMapping("/register")
    public ResponseEntity<?> register(@RequestBody User user) {
        try {
            User savedUser = userService.register(user);
            return ResponseEntity.ok(savedUser);
        } catch (Exception e) {
            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(e.getMessage());
        }
    }
}

5. 测试注册功能

使用Postman或其他工具发送POST请求到http://localhost:8080/api/users/register，请求体为以下JSON格式：

{
    "username": "test",
    "password": "test123",
    "email": "test@example.com"
}

如果成功注册，响应码为200，响应体为注册的用户信息；如果失败，响应码为400，响应体为错误信息。