表和实体映射的休眠查询异常

Question

我收到如下错误：

org.hibernate.hql.internal.ast.QuerySyntaxException: Employee is not mapped [from Employee]; nested exception is java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: Employee is not mapped [from Employee]",
    "trace": "org.springframework.dao.InvalidDataAccessApiUsageException: org.hibernate.hql.internal.ast.QuerySyntaxException: Employee is not mapped [from Employee];

我已经创建了如下所示的模态

@Entity
@Table(name="employee_list")
public class Employee {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column
    private Integer id;

    @Column
    private String name;

    @Column
    private String gender;

    @Column
    private String department;

    @Column
    private Date dob;
    // getters/setters
}

我的道实现：

@Repository
public class EmployeeDAOImpl implements EmployeeDAO {

    @Autowired
    private EntityManager entityManager;

    @Override
    public List<Employee> get() {
        Session currentSession = entityManager.unwrap(Session.class);
        Query<Employee> query =  currentSession.createQuery("from Employee", Employee.class);
        List<Employee> list = query.getResultList();
        return list;
    }
}

我错过了一些东西。
我无法确定到底是什么。

Answer 1

尝试将@EntityScan(basePackage="*the package where your entity lies*")（或类似）注释添加到您的EmployeeDAOImpl 类。查询看起来没问题。对于 HQL，您必须使用类型名称，而不是表名称。 如果你使用 Spring JPA，你也可以尝试使用 JPARepository 或 CrudRepository 等提供的接口

Answer 2

HQL 应如下所示：

currentSession.createQuery("select e from Employee e", Employee.class);

另外，您可以使用 Criteria API：

currentSession.createCriteria(Employee.class).list();

有用的参考资料：

• Is Hibernate Criteria API Deprecated and if so what API should we use?
• Why is criteria query deprecated in Hibernate 5?

Answer 3

@Entity 应该来自 JPA 库，而不是休眠库。此外，您应该在查询中使用实体名称：

session.createQuery("from Employee", Employee.class);