如何编写休眠OneToMany关系的hql查询？

Question

I have the following classes laid out like so:

class User {
    @Id
    private long id;

    @OneToMany(fetch = FetchType.EAGER,cascade = CascadeType.ALL)
    Set<UserRole> userRoles;
}

class UserRole {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", unique = true, nullable = false)
    private int id;

    @Column(name = "role", nullable = false, length = 45)
    private String role;
   }

I'm attempting to query for users that have a specific role (in this case, all users with the role ROLE_ADMIN), using the following query:

    org.hibernate.query.Query<User> userQuery=session.createQuery("from User as mc where mc.userRoles in (from UserRole as ur where ur.role in (:uRoles))",User.class);
    Set<String> roles = new HashSet<String>();
    roles.add("ROLE_ADMIN");
    userQuery.setParameterList("uRoles", roles);
    List<User> admins = userQuery.getResultList();

However, the query is not returning any results.

Answer 1

session.createQuery(
  "from User as user join user.userRoles as userRole where userRole.role in :roles")
  .setParameter("roles", Arrays.asList("ROLE_ADMIN"))
  .getResultList();