Null values as part of an unique key

DriesSchelfhout · **Posted:** Wed May 31, 2006 10:11 am

I'm using the Hibernate Tool 3.1 to map an old database(oracle 9.2).
The database didn't had any primary keys defined, so I use hibernate.reveng.xml to define the colums that make an unique key(with composite-id).
With hibernate tools I create my 'Domain Code' and '.hbm.xml' files.

Now when I try to get an object with get and I give a long and a Short variable, I get my Object back without any problems.
But when I want to get the object where one of the variable has the value 'null' in my database, I get a 'java.lang.NullPointerException'.
When I look in my database there is only one row that corresponds with it.
I have asked around I have heard that hibernate has problems with null values. Is there any way around, so the null values aren't a problem?

Example:

Part of TestClass working code:

Code:

Kssv k = kssvDao.getKssv(new KssvId(11, new Short("1")));

Part of TestClass failling code:

Code:

Kssv k = kssvDao.getKssv(new KssvId(11, null));

Constructor of KssvId

Code:

    public KssvId(long kssvnr, Short kssvagentnr) {
        this.kssvnr = kssvnr;
        this.kssvagentnr = kssvagentnr;
    }

Part of KssvDaoImpl:

Code:

    public Kssv getKssv(KssvId inId) {
        Validate.notNull(inId, "inId cannot be null");
        try {
            return (Kssv) this.getHibernateTemplate().get(Kssv.class, inId);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

max · **Posted:** Wed May 31, 2006 11:11 am

a primary key/identifier cannot contain null.