我遇到了使用Hibernate和Spring MVC的问题,即如果我在查询中使用JOIN,就会收到一个没有任何细节的500错误。有人可以帮我吗?
这两个表是:
用户:
这两个表是:
用户:
@Entity
@Table(name = "user")
public class User {
@Id
@GeneratedValue(generator="increment")
@GenericGenerator(name="increment", strategy = "increment")
@Column(name = "id_user")
private Long id;
@Column(name = "name")
private String name;
@Column(name = "surname")
private String surname;
@OneToMany(mappedBy = "contentManager")
private Set<Project> projects;
...
项目:
@Entity
@Table(name = "projects")
public class Project {
@Id
@GeneratedValue(generator="increment")
@GenericGenerator(name="increment", strategy = "increment")
@Column(name = "id_project")
private Long id;
@Column(name = "project_name")
private String name;
@Column(name = "project_language")
private String language;
@ManyToOne(fetch=FetchType.LAZY)
@JoinColumn(name = "id_content_manager")
@JsonBackReference
private User contentManager;
...
控制器类方法:
@Transactional
@RequestMapping(value = "/", method = RequestMethod.GET)
public @ResponseBody List<Project> home(Locale locale, Model model) {
Session session=new Configuration().configure().buildSessionFactory().getCurrentSession();
session.beginTransaction();
List<Project> result = (List<Project>) session.createQuery("FROM projects p JOIN p.contentManager").getResultList();
session.getTransaction().commit();
session.close();
return result;
}
我能帮你吗?
编辑:Tomcat 控制台:
WARN : org.hibernate.orm.connections.pooling - HHH10001002: Using Hibernate built-in connection pool (not for production use!)
Hibernate: select project0_.id_project as id_proje1_0_0_, user1_.id_user as id_user1_1_1_, project0_.id_content_manager as id_conte4_0_0_, project0_.project_language as project_2_0_0_, project0_.project_name as project_3_0_0_, user1_.name as name2_1_1_, user1_.surname as surname3_1_1_ from projects project0_ inner join user user1_ on project0_.id_content_manager=user1_.id_user
Project
,而不是projects
。我很确定你在查询中添加的连接操作并不能实现你想要的功能。最重要的是,请阅读Spring文档,了解如何在Spring中集成JPA。你现在的做法完全错误。 - JB Nizet