[jbdevstudio-users] Composite key joins in hibernate

[Sameer Sarmah]

I am using hibernate to persist two tables,`Project` and `Department`.

`Department` table has a composite primary key `DeptCompID`.

        @Embeddable
        public class DeptCompID implements Serializable
        {

            @Column(name = "DeptID")
            private int DeptID;

            @Column(name = "RoleID")
            private int RoleID;

            //getters and setters
        }

    @Entity
    public class Department implements Serializable
    {

        @EmbeddedId    
        private DeptCompID id;

         private String name;

        @OneToOne(mappedBy="department",targetEntity = Project.class)
        private Project pro;

        //getters and setters
    }

    @Entity
    public class Project 

    {
        @Id
        private int ProId;


        @OneToOne(targetEntity = Department.class)
        @MapsId("DeptID")
        @JoinColumns({    
        @JoinColumn(name = "RoleID", referencedColumnName = "RoleID"),
        @JoinColumn(name = "DeptID", referencedColumnName = "DeptID")
        })
         private Department department;

    //getters and setters
    }


**Code to persist the tables**


                Department department = new Department();
                department.setName("HR");
                DeptCompID cpk=new DeptCompID();
                cpk.setRoleID(10);
                cpk.setDeptID(60);
                department.setId(cpk);

                Project pro=new Project();
                pro.setDepartment(department);
                pro.setProId(10);
                department.setPro(pro);
                session.save(department);
                session.save(pro);

Everytime I persist the tables Project and Department the `DeptID` column in `Project` table is always null when it should be 60.
why is `@MapsId("DeptID")` not working?Could some provide a resolution.

Posted by forums
Original post: https://community.jboss.org/message/878168#878168