java.lang.IllegalArgumentException:期待IdClass映射

Question

我已为我的实体配置了复合主键,Employee如下所示

Employee.java:

@Entity
@Table(name="employee")
@Proxy(lazy=false)
@IdClass(EmployeeId.class)
public class Employee implements Serializable {
    private static final long serialVersionUID = 1L;

    private EmployeeId employeeId;
    private Person person;
    private Branch branch;
    private boolean isActive;

    public Employee() {

    }    

    @EmbeddedId
    @AttributeOverrides({
        @AttributeOverride(name="person", column = @Column(name="person_id")),
        @AttributeOverride(name="branch", column = @Column(name="branch_id"))})

    public EmployeeId getEmployeeId() {
        return employeeId;
    }

    public void setEmployeeId(EmployeeId employeeId) {
        this.employeeId = employeeId;
    }

    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="person_id")
    public Person getPerson() {
        return person;
    }

    public void setPerson(Person person) {
        this.person = person;
    }


    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="branch_id")
    public Branch getBranch() {
        return branch;
    }

    public void setBranch(Branch branch) {
        this.branch = branch;
    }

    @Column(name="is_active")
    public boolean getIsActive() {
        return isActive;
    }

    public void setIsActive(boolean isActive) {
        this.isActive = isActive;
    }

}

EmployeeId.java:

@Embeddable
public class EmployeeId implements Serializable {
    private static final long serialVersionUID = 1L;

    private Person person;
    private Branch branch;

    public EmployeeId() {

    }

    public EmployeeId(Person argPerson, Branch argbranch) {
        this.person = argPerson;
        this.branch = argbranch;
    }


    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="person_id", insertable=false, updatable=false)
    public Person getPerson() {
        return person;
    }
    public void setPerson(Person person) {
        this.person = person;
    }

    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="branch_id", insertable=false, updatable=false)
    public Branch getBranch() {
        return branch;
    }
    public void setBranch(Branch branch) {
        this.branch = branch;
    }
}

我SessionFactory使用类创建了一个bean,org.springframework.orm.hibernate5.LocalSessionFactoryBean并将all映射hbm.xml为MappingLocations.

我的代码抛出以下错误:

Caused by: java.lang.IllegalArgumentException: expecting IdClass mapping
at org.hibernate.metamodel.internal.AttributeFactory$3.resolveMember(AttributeFactory.java:971)
at org.hibernate.metamodel.internal.AttributeFactory$5.resolveMember(AttributeFactory.java:1029)
at org.hibernate.metamodel.internal.AttributeFactory.determineAttributeMetadata(AttributeFactory.java:451)
at org.hibernate.metamodel.internal.AttributeFactory.buildIdAttribute(AttributeFactory.java:128)
at org.hibernate.metamodel.internal.MetadataContext.buildIdClassAttributes(MetadataContext.java:337)
at org.hibernate.metamodel.internal.MetadataContext.applyIdMetadata(MetadataContext.java:269)
at org.hibernate.metamodel.internal.MetadataContext.wrapUp(MetadataContext.java:190)
at org.hibernate.metamodel.internal.MetamodelImpl.initialize(MetamodelImpl.java:219)
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:296)
at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:476)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:707)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:723)
at org.springframework.orm.hibernate5.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:504)
at org.springframework.orm.hibernate5.LocalSessionFactoryBean.afterPropertiesSet(LocalSessionFactoryBean.java:488)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFac

我怎样才能避免这个错误？我正在使用spring-orm-4.3.1-RELEASE和hibernate-core-5.2.0.Final.

更新

我创建了一个示例项目,运行时出现以下错误...

Caused by: org.hibernate.AnnotationException: Property of @IdClass not found in entity sample.domain.Employee: employee

请参阅代码:https://www.dropbox.com/s/axr8l01iqh0qr29/idclass-using-hibernate5.tar.gz？dl = 0

我做错了什么？请在这里提供您的意见

Answer 1

你的情况对应的章节2.4.1主键对应派生身份的的JPA 2.1规范。

的身份Employee从身份得到的就是Person和Branch。您尚未显示其中任何一个的代码，因此我假设它们具有简单的主键。在这种关系中，Person和Branch是“父实体”并且Employee是“依赖”实体。

的 IDEmployee可以使用IdClass或映射EmbeddedId，而不是同时使用。

请参阅第2.4.1.1章派生身份的规范。

如果要使用IdClass，则：

id类的属性名称与依赖实体类的Id属性名称必须对应如下：

• 将Id在实体类属性，在ID类对应的属性必须具有相同的名称。

...

• 如果Id实体中的属性与父实体是多对一或一对一关系，则 id 类中对应的属性必须是 (...)Id父实体的属性类型。

所以你的类看起来像这样（省略了getter、setter、多余的注释等）

@Entity
@IdClass(EmployeeId.class)
public class Employee {
   @Id
   @ManyToOne
   private Person person;
   @Id
   @ManyToOne
   private Branch branch;
}

public class EmployeeId {
    private Long person; // Corresponds to the type of Person ID, name matches the name of Employee.person
    private Long branch; // Corresponds to the type of Branch ID, name matches the name of Employee.branch
}

如果您使用EmbeddedId，则：

如果依赖实体使用嵌入的id来表示其主键，则关系属性对应的嵌入id中的属性必须与父实体的主键类型相同，并且必须由MapsId应用于关系的注解指定属性。注释的value元素MapsId必须用于指定关系属性对应的嵌入 id 中的属性名称。

代码如下所示：

@Entity
public class Employee {
   @EmbeddedId
   private EmployeeId id;
   @ManyToOne
   @MapsId("personId") // Corresponds to the name of EmployeeId.personId
   private Person person;
   @ManyToOne
   @MapsId("branchId") // Corresponds to the name of EmployeeId.branchId
   private Branch branch;
}

@Embeddable
public class EmployeeId {
    private Long personId; // Corresponds to the type of Person ID
    private Long branchId; // Corresponds to the type of Branch ID
}

Answer 2

改成：

@Entity
@Table(name = "employee")
@Proxy(lazy = false)
@IdClass(EmployeeId.class)
public class Employee implements Serializable {
private static final long serialVersionUID = 1L;

private EmployeeId id;
private Person person;
private Branch branch;
private boolean isActive;

public Employee() {

}

@EmbeddedId
@AttributeOverrides({@AttributeOverride(name = "person", column = @Column(name = "person_id") ),
    @AttributeOverride(name = "branch", column = @Column(name = "branch_id") )})

public EmployeeId getId() {
return id;
}

public void setId(EmployeeId id) {
this.id = id;
}

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "person_id")
public Person getPerson() {
return person;
}

public void setPerson(Person person) {
this.person = person;
}

@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "branch_id")
public Branch getBranch() {
return branch;
}

public void setBranch(Branch branch) {
this.branch = branch;
}

@Column(name = "is_active")
public boolean getIsActive() {
return isActive;
}

public void setIsActive(boolean isActive) {
this.isActive = isActive;
}

}