m_ssn = new Session(new MemoryEngine());
m_ssn = new Session(new MemoryEngine(), new DynamicQuerySource());
    public void sessionTest(TestResult result) {        result.startTest(this);        PDL pdl = new PDL();        pdl.emit(Root.getRoot());        m_model = Model.getInstance("test");        initializeModel();        m_ssn = new Session(new MemoryEngine());        initializeData();        m_ssn.commit();        test(m_root);        test(m_one);        result.endTest(this);    }