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

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private UUID userId;

    @Column(nullable = false)
    @NotBlank(message = "Name is Required")
    private String name;

    @Column(nullable = false)
    @NotBlank(message = "Password hash is required")
    @Size(min = 8, message = " Password must be more than 8 characters and alphanumeric ")
    @Alphanumeric(message = "password must be alpahanumeric")

    private String hash;

    @Column(nullable = false, unique = true)
    @NotBlank(message = "Username is required")
    @Size(min = 5, max = 20, message = "Username must be between 5 and 20 characters")
    private String username;

    // a temporary variable to use in controller to check if roleId is valid in the
    // Role entity
    @Column(name = "user_role", insertable = false, updatable = false)
    private Integer roleId;

    @ManyToOne
    @JoinColumn(name = "user_role", nullable = false, referencedColumnName = "id")
    private Role role;

    public User() {

This is how I setup my user class in a model package.

 @PostMapping("/register")
    public ResponseEntity<String> registerUser(@RequestBody @Valid User user, BindingResult bindingResult) {

        // Check for validation errors
        if (bindingResult.hasErrors()) {
            String errorMessage = bindingResult.getAllErrors().get(0).getDefaultMessage();
            logger.info("Validation error: {}", errorMessage);
            return new ResponseEntity<>("Validation error: " + errorMessage, HttpStatus.BAD_REQUEST);
        }

        // Check if username already exists
        Optional<User> userOptional = userRepository.findByUsername(user.getUsername());
        if (userOptional.isPresent()) {
            return new ResponseEntity<>("Username already exists", HttpStatus.BAD_REQUEST);
        }

        // Ensure roleId is provided in the JSON request
        Integer roleId = user.getRoleId();
        if (roleId == null) {
            return new ResponseEntity<>("Role ID is required", HttpStatus.BAD_REQUEST);
        }

        // Fetch the Role from repository based on roleId
        Optional<Role> optionalRole = roleRepository.findById(roleId);
        if (!optionalRole.isPresent()) {
            return new ResponseEntity<>("Role not found", HttpStatus.BAD_REQUEST);
        }

        // Set the fetched Role to the User object
        Role role = optionalRole.get();
        user.setUserRole(role);

        // Save the user to the database
        userRepository.save(user);

        return ResponseEntity.ok("User registered successfully");
    }

And my Postmapping for registering. It seems that my controller does not run any validations and skips the first if block statement, I am able to register with empty fields. I started Java recently and this is my first springboot project. Still learning my way around.

I checked if I have the right dependencies

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>

Also tried creating a UserDto class but seem to be facing more issues.

public class UserDto {


    @NotBlank(message = "Name is Required")
    private String name;


    @NotBlank(message = "Password hash is required")
    @Size(min = 8, message = " Password must be more than 8 characters and alphanumeric ")
    @Alphanumeric(message = "password must be alpahanumeric")
    private String hash;


    @NotBlank(message = "Username is required")
    @Size(min = 5, max = 20, message = "Username must be between 5 and 20 characters")
    private String username;

    // a temporary variable to use in controller to check if roleId is valid in the
    // Role entity

    private Integer roleId;

    private Role role;

    public User toUser() {
        return new User()
                .setName(name)
                .setUsername(username)
                .setHash(hash)
                .setRoleId(roleId)
                .setUserRole(role);
    }
}

In my public User toUser() im getting setUsername(String) not resolved. Ive checked if ive properly imported everything and when i created this file i removed the validations from my Users class. Not sure how to get about it