我可以协助您进行翻译。以下是您需要翻译的内容:
经理实体:
据我了解,@NamedSubgraph.type 应该用于指定要获取的实体子类属性。Hibernate 是否忽略 @NamedSubgraph 注释中 type=Manager.class 属性,还是我漏掉了什么?
我正在使用Hibernate 4.3.8.FINAL,并拥有以下模型:一个部门有多个员工,而一个员工可以成为经理。
员工实体:
@Entity
@Table(name = "employee", schema = "payroll")
@Inheritance(strategy = InheritanceType.JOINED)
public class Employee
{
@Id
private Long id;
@Basic(optional = false)
@Column(name = "name")
private String name;
@JoinColumn(name = "department_id", referencedColumnName = "id")
@ManyToOne(optional = false, fetch = FetchType.LAZY)
private Department department;
}
经理实体:
@Entity
@Table(name = "manager", schema = "payroll")
@Inheritance(strategy = InheritanceType.JOINED)
@PrimaryKeyJoinColumn(name = "employee_id", referencedColumnName = "id")
public class Manager extends Employee
{
@Basic(optional = false)
@Column(name = "car_allowance")
private boolean carAllowance;
}
部门实体:
@NamedEntityGraph(
name = "Graph.Department.FetchManagers",
includeAllAttributes = false,
attributeNodes = {
@NamedAttributeNode(value = "name"),
@NamedAttributeNode(value = "employees", subgraph = "FetchManagers.Subgraph.Managers")
},
subgraphs = {
@NamedSubgraph(
name = "FetchManagers.Subgraph.Managers",
type = Employee.class,
attributeNodes = {
@NamedAttributeNode(value = "name")
}
),
@NamedSubgraph(
name = "FetchManagers.Subgraph.Managers",
type = Manager.class,
attributeNodes = {
@NamedAttributeNode(value = "carAllowance"),
}
)
}
)
@Entity
@Table(name = "department", schema = "payroll")
public class Department
{
@Id
private Long id;
@Basic(optional = false)
@Column(name = "name")
private String name;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "department", fetch = FetchType.LAZY)
private Set<Employee> employees;
}
如 Department 实体所示,我正在尝试创建一个@NamedSubgraph,以加载所有员工并获取 Manager.carAllowance。但是我收到以下错误:
Unable to locate Attribute with the the given name [carAllowance] on this ManagedType [com.nemea.hydra.model.test.Employee]
据我了解,@NamedSubgraph.type 应该用于指定要获取的实体子类属性。Hibernate 是否忽略 @NamedSubgraph 注释中 type=Manager.class 属性,还是我漏掉了什么?