Org.hibernate.exception.constraintViolationException beim Registrieren der Benutzer ⇐ Java

[Anonymous]

Ich versuche, Registrierungsprozess zu erstellen. Dies ist mein Code: < /p>

public class UserRegistrationDto {

private String firstName;
private String lastName;
private String password;
private String confirmPassword;
private String email;
private String confirmEmail;
private Boolean terms;
}
< /code>

Rollenklasse: < /p>

@Entity
public class Role {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
private String name;
< /code>

Benutzerklasse: < /p>

@Entity
@Table(uniqueConstraints = @UniqueConstraint(columnNames = "email"))
public class User {

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

private String firstName;
private String lastName;
private String email;
private String password;

@ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
@JoinTable(
name = "users_roles",
joinColumns = @JoinColumn(
name = "user_id", referencedColumnName = "id"),
inverseJoinColumns = @JoinColumn(
name = "role_id", referencedColumnName = "id"))
private Collection roles;
}
< /code>

Service: < /p>

@Service
public class UserServiceImpl implements UserService {

(...)
public User save(UserRegistrationDto registration){
User user = new User();
user.setFirstName(registration.getFirstName());
user.setLastName(registration.getLastName());
user.setEmail(registration.getEmail());
user.setPassword(passwordEncoder.encode(registration.getPassword()));
user.setRoles(Arrays.asList(new Role("ROLE_USER")));
return userRepository.save(user);
}

private Collection