Transaction issue :: hibernate

getSession() –> the java doc says it will create a new session/ continue with the existing one based on getHibernateTemplate().setAllowCreate(…); set to true/ false.

How ever, i found the things to be diffarent. I had a 2 DAOs one executing: getHibernateTemplate().find(..); the other using getSession().createCriteria(..); They are wrapped by the same transaction interceptor. What i found is when the 2nd DAO runs the hibernate throws illegal state exception.

Why?? The getSession() always tries to crate a new session, if the setAllowCreate is set to false, then it throws illegal argument exception. Why this devaiation??? as always only god knows it.

To get the current session in 2nd DAO, i found the fix: getHibernateTemplate().getSessionFactory().getCurrentSession(); and things went off very fine.

getHibernateTemplate().find() / query.list() returns list with null values

So the problem stmt is as follows

1. The Entity primary key is mapped as composite-id in hbm files. i.e.. all columns/ multiple columns of the entity is taken as composite key. This gnerally happens when u use code generatoros. 
2. now you say the below in criteria query

   Criteria criteria = getSession().createCriteria(CompositeKeyEntity.class);
   criteria = criteria.add(Restrictions.in("id.subKey", list));
   List<CompositeKey> list = criteria.list();

   
   
   
   
3. The above returns a list with entities are null.
   
   
   
   1. why? Tracing the src code figured out that hibernate checks each of the values of primary keys. and when ever he finds one of the value as null doesn’t return the object. (org.hibernate.type.ComponentType.hydrate())
      
   2. This is logical as we shouldn’t have nulls in primary keys. But the problem is its not documented anywhere!
   
   
4. so the fix: make all composite key columns as not-null; and give a default to each of the column.

 

Let me know if it helps.