这是我的第一个问题。
Spring Data JPA Many to Many with extra column User and Roles
现在我已经创建了正确的表,但无法使其用于更新。
以下是代码:
使用者JAVA
@Entity
@Table(name = "users")
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String username;
@OneToMany(mappedBy="user", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.LAZY)
private List<UserRole> roles;
// getters and setters
}
角色JAVA
@Entity
@Table(name = "roles")
public class Role {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
// getters and setters
}
用户角色。JAVA
@Entity
@Table(name = "users_to_role")
public class UserRole implements Serializable {
@Id
@ManyToOne
@JoinColumn(name = "user_id")
private User user;
@Id
@ManyToOne
@JoinColumn(name = "role_id")
private Role role;
private Date createdAt;
public UserRole(){}
public UserRole(User user, Role role, Date date) {
this.user = user;
this.role = role;
this.createdAt = date;
}
// getters and setters
}
控制器
@RestController
public class APIController {
@Autowired
RoleRepository roleRepository;
@Autowired
UserRepository userRepository;
@ResponseBody
@RequestMapping(value = "create", method = RequestMethod.GET)
public String create(){
//Insert test - WORKING BUT NOT SURE IF ITS RIGHT WAY
List<UserRole> userRoles = new ArrayList<>();
Role role = roleRepository.getOne((long) 1);
//Create user
User user = new User();
user.setUsername("test");
//Create userRole
userRoles.add(new UserRole(user, role, new Date()));
user.setRoles(userRoles);
userRepository.save(user);
return "created";
}
@ResponseBody
@RequestMapping(value = "edit", method = RequestMethod.GET)
public String edit(){
//Edit test - NOT working
List<UserRole> userRoles = new ArrayList<>();
Role role = roleRepository.getOne((long) 2);
//get user from db
User user = userRepository.getOne((long) 1);
//Create userRole
userRoles.add(new UserRole(user, role, new Date()));
// WAS FIRST ATTEMPT using user.setRoles(userRoles); but got error and use
//https://stackoverflow.com/questions/9430640/a-collection-with-cascade-all-delete-orphan-was-no-longer-referenced-by-the-ow
//user.setRoles(userRoles);
user.getRoles().clear();
user.getRoles().addAll(userRoles);
userRepository.save(user);
return "done";
}
}
我得到了这个错误:
通用域名格式。mysql。jdbc。例外。jdbc4。MySQLIntegrityConstraintViolationException:列“user_id”不能为null
