ORA-01400: cannot insert NULL in #manytomany unidierctional - jpa

Question

I am inserting a User object with roles(existing) roles .
It is giving me unable insert null in user_role.id
Schema:
#Entity
#Table(name = "user_data")
public class User extends Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
/**
* user can have set of roles profiles
*/
#ManyToMany(cascade = {CascadeType.ALL} ,fetch=FetchType.EAGER)
#JoinTable(name = "user_role", joinColumns = { #JoinColumn(name = "user_id", referencedColumnName = "id") }, inverseJoinColumns = { #JoinColumn(name = "role_id", referencedColumnName = "id") })
private Set<Role> roles;
}
#Entity #Table(name = "role")
public class Role extends Serializable {
private static final long serialVersionUID = -5954247513572163065L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Column(name = "name")
private String name;
#ManyToMany
#JoinTable(name = "role_permission", joinColumns = { #JoinColumn(name = "role_id",
referencedColumnName = "id") },
inverseJoinColumns = { #JoinColumn(name = "permission_id",
referencedColumnName = "id") })
private Set<Permission> permissions;
[...]
}
Now when i am trying to create user it is giving me the exception
java.sql.SQLIntegrityConstraintViolationException: ORA-01400: cannot insert NULL into ("USER_ROLE"."ID")
For creating a user I am using spring repository code as below:
#Override
#Transactional(readOnly = false, propagation = Propagation.REQUIRES_NEW)
public User createUser(User user) throws BusinessException {
List<Error> errors = new ArrayList<Error>();
validateUserRoles(user ,errors);
if ( errors.size() > 0 )
{
throw new BusinessException(errors);
}
user.setUserIdentifier(user.getUserIdentifier().trim());
logger.info("Creating User with username: " + user.getUserIdentifier());
return this.userRepositotry.save(user);
}
private void validateUserRoles(User user ,List<Error> errors) {
Set<Role> roles = new HashSet<Role>();
if (user.getRoles() != null)
{
for(Role role : user.getRoles())
{
Role r = null;
if(role.getId() != null)
{
r = this.roleRepository.findOne(role.getId());
} else if( role.getName() != null )
{
r = this.roleRepository.findByName(role.getName());
}
if(r == null)
{
errors.add(new Error(ErrorCode.INVALID_ARGUMENTS,"Invalid user Role.",r));
} else
{
roles.add(r);
}
}
}
user.setRoles(roles);
}

Answer 1

Your user_role join table has an id column, that Hibernate doesn't know about. All hibernate knows about is the role_id and user_id columns. The id column isn't useful, and you should remove it from the user_role table. If you leave it there, you need to make it nullable, or to make it have a default value.