struts + hibernate confused on what type of mapping to use

[vanlalhmangaiha khiangte]

Hi all,

I am using struts2 + hibernate for current project.
I have a student_tab table and a registration_tab table.

1) A student record will be entered first
2) Based on the "serial_no" of the student table , i will create a registration for it in the registration_tab.
3) Student may / may not have registration

My problems is as below :
1) There is a query,edit,delete,create page for Student and Registration.
2) In student query page , only the student table will be displayed. (edit and delete students exists as links) << this is working >>
3) In registration query page, students table will be displayed ( but very less information like rollno,class etc .. ) along with the registration table (all the datas)
Here a create , edit ,delete registration link will exists << this is the part where the problem occurs >>
4) Even if there is a valid record in student table and in registration table with same "serial_no" , regninfo is always containing all null values.

When i save student object only student table should be saved and when i save registration object only registration table should be saved
What kind of mapping should i use? What will be the approach for this kind of design?


Thanks in advance,
Vanlal



Student.java

@Entity
@Table(name = "student_tab")
public class Student implements Serializable {
	
	Registration regninfo=new Registration();
	
           //I do not have any setter method for regninfo since i don't want regninfo to be saved when i save student
	@OneToOne
	@JoinColumn(name = "serial_no",referencedColumnName="serialno")	
	public Registration getRegn() {
		return regninfo;
	}
	 
	@Id
	@GeneratedValue
	@Column(name = "serial_no")
	private Long serial_no;
	
	@Column(name="std_fname",nullable=false,length=50)
	private String std_fname;
	
	@Column(name = "std_lname",nullable=true,length=50)
	private String std_lname;

       // Other data type ...

Registration.java

@Entity
@Table(name = "registration_tab")
public class Registration implements Serializable {
	
	
	private Student student;
	
	@OneToOne(mappedBy = "serialno")
	public Student getStudent() {
		return student;
	}

	@Id
	@GeneratedValue
	@Column(name = "id")
	private Long id;
	
	@Min(1)
	@Column(name = "serialno")
	private int serialno;
	
	@Column(name = "validfrom",nullable = true, length = 20)
	private Date validfrom;
	
	@Column(name = "validto",nullable = true, length = 20)
	private Date validto;

        // Other data type ...