Please help- My application was working fine until today. Today I got the exception "could not deserialize". java.io.eofException. And sometimes I was able to get the data. The problem was intermittent. What could be the issue here?

I am trying to get the data using following code
Session session = SessionFactory.getInstance(SessionContext.DISTRIBUTED).getSession();
session.beginTransaction();
List results;
try {
Criteria cri = session.createCriteria(Filter.class);
cri.add(Restrictions.eq( "user", userVO.user() ));
setLazyMode(cri);
results = cri.list();
session.getTransaction().commit();
} finally {
rollbackIfStillOpen(session);
}