public PersistentCollection retrieve(Query query) { return POS.getPersistentCollection(this, new DataSet(this, query));
public Object retrieve(ObjectType obj, Object id) { PersistentCollection pc = retrieve(m_qs.getQuery(obj, id)); Cursor c = pc.getDataSet().getCursor(); if (c.next()) { Object result = c.get(); if (c.next()) { throw new IllegalStateException ("query returned more than one row"); } return result; } else { return null; }
    public PersistentCollection retrieve(Query query) {        return POS.getPersistentCollection(this, new DataSet(this, query));    }