我在使用嵌入式注釋的JPA中嘗試關系,但我無法成功運行它,

這里我的數據庫sql腳本如下,

create table TBL_COLLEGE(

id integer primary key generated always as identity (start with 1000, increment by 5),

name varchar(50)

)

create table TBL_COURSE(

Id integer primary key generated always as identity (start with 10, increment by 1),

college_Id integer references TBL_COLLEGE,

name varchar(50)

)

以下是JPA的代碼,

@Embeddable

public class Course {

...

...

..

@Id

@GeneratedValue(strategy= GenerationType.IDENTITY)

@Column(name="ID")

private Integer courseId;

@Column(name="NAME")

private String courseName;

@Column(name="COLLEGE_ID")

private Integer collegeId;

....

// getter and setter

}

這是學院的地圖,

@Entity

@Table(name="TBL_COLLEGE")

public class College implements Serializable{

@Id

@GeneratedValue(strategy= GenerationType.IDENTITY)

@Column(name="ID")

private Integer collegeId;

...

..

@ElementCollection(targetClass=Course.class,fetch= FetchType.LAZY)

@CollectionTable(name="TBL_COURSE",joinColumns=@JoinColumn(name="COLLEGE_ID"))

private Set course;

..

// getter and setter

}

但是,如果我嘗試堅持學院與課程集合,

它給了我一個例外,

ERROR: HCANN000002: An assertion failure occurred (this may indicate a bug in Hibernate)

org.hibernate.annotations.common.AssertionFailure: Declaring class is not found in the inheritance state hierarchy: com.entities.Course

....

..

你能告訴我我的做法是否錯誤,

或者我對@CollectionTable的理解仍然很少,

我錯了

總結

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