Primary key @OneToOne mapping in Hibernate (JPA)

My main objective is to save/insert as many POJO's as possible with the minimum # of calls to save method. That's why I'm relate them.

But there is a special relationship which it's not clearly documented on the official documentation, and that's why you'll see this entry here :)

.The problem is that I have 2 tables COURSE_ACCESS and COURSE_ACCESS_STATUS:

---------------
COURSE_ACCESS
---------------
*id
...
---------------

---------------------
COURSE_ACCESS_STATUS
---------------------
*course_access_id
...
---------------------

The relationship is 1:1. COURSE_ACCESS is the "parent" table, because that one has the SEQUENCE which generates the PK on "id" column.

Now what I want is when I save COURSE_ACCESS, COURSE_ACCESS_DATA should be saved too. Just like this CourseAccess courseAccess = Transformer.transform(user, enrollmentDetails, accessStartDate, new CourseAccess()); CourseAccessStatus courseAccessStatus = Transformer.transform(courseAccess, new CourseAccessStatus()); courseAccess.setCourseAccessStatus(courseAccessStatus);//Persisting CourseAccessStatus into CourseAccess this.courseAccessHomeService.save(courseAccess); //Instead of 2 DAO calls
How I did it?
@Entity @Table(name = "COURSE_ACCESS") public class CourseAccess implements Serializable { @Id @Column(name = "ID", unique = true, nullable = false, insertable = true, updatable = true, length = 40) @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="courseAccessSequenceGenerator") @GenericGenerator(name = "courseAccessSequenceGenerator", strategy = "kaptest.util.domain.VarcharSequenceGenerator", parameters = {@Parameter(name = "sequence", value = "OI_SEQUENCE_NUMBER")}) private String id; … @OneToOne(cascade=CascadeType.ALL, fetch=FetchType.LAZY, targetEntity=CourseAccessStatus.class) @PrimaryKeyJoinColumn(name="ID", referencedColumnName="course_access_id") private CourseAccessStatus courseAccessStatus; }
@Entity @Table(name = "COURSE_ACCESS_STATUS") @org.hibernate.annotations.GenericGenerator(name="courseAccessFKGenerator",strategy="foreign", parameters=@org.hibernate.annotations.Parameter(name="property",value="courseAccess")) public class CourseAccessStatus implements java.io.Serializable { @Id @GeneratedValue(generator="courseAccessFKGenerator") @Column(name = "course_access_id", unique = true, nullable = false, length = 40) private String courseAccessId; … @OneToOne(cascade=CascadeType.ALL, fetch=FetchType.EAGER, targetEntity=CourseAccess.class) @PrimaryKeyJoinColumn(name="course_access_id", referencedColumnName="ID") private CourseAccess courseAccess; }

And that's it!!! Easy isn't it?