ManyToMany HQL Join - 期望加入的路径

时间:2016-06-23 13:10:29

标签: java hibernate jpa spring-data-jpa

我有以下实体:

1.User entity。

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

        @Id
        @GeneratedValue
        private int userId;

        @Column
        private String username;

        @Column
        private String password;

        @ManyToMany(fetch=FetchType.EAGER)
        @JoinTable(name = "USER_ROLE", joinColumns={@JoinColumn(name="userId")}, inverseJoinColumns={@JoinColumn(name="roleId")})
        private List<Role> roles;

//+setters and getters}
  1. 角色实体。

    @Entity
    @Table(name="ROLE")
    public class Role {
    
        @Id
        @GeneratedValue
        private long roleId;
    
        @Column
        private String name;
    
        @ManyToMany(mappedBy="roles", fetch=FetchType.EAGER)
        private List<User> users;
    //+setters and getters
    }
    
  2. 现在,我正在尝试在存储库中提取具有其角色(role_name)的用户(用户名)。我希望为Spring Security Auth做这件事。 这是我的HQL代码:

    @Query("select u.username, r.name from User u"+
                " join User_Role ur on u.userId = ur.userId"+
                " join Role r on ur.roleId = r.roleId"+
                " where u.username =:username")
    

    ......我收到了这个错误:

    Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: Path expected for join! [select u.username, r.name from ro.app.mmapp.persistence.entity.User u join User_Role ur on u.userId = ur.userId join Role r on ur.roleId = r.roleId where u.username =:username]
    

    我尝试了多种类型的连接,但得到了相同的结果。 谁可以帮我提一些建议?

    谢谢!

1 个答案:

答案 0 :(得分:1)

任何基本的JPQL教程都会告诉您加入一个关系。

select u.username, r.name from User u JOIN u.roles r WHERE u.username =:username