protected void verify() {
    if (!employee.getAddress().getCity().equals("null")) {
      throw new TestErrorException("Null value not converted correctly for string.");
    }

    if (employee.getSalary() != -1) {
      throw new TestErrorException("Null value not converted correctly for int.");
    }
  }
  protected void setup() {
    // save current null values for later restoration
    saveDefaultDefaultNullValues = ConversionManager.getDefaultManager().getDefaultNullValues();
    saveDefaultNullValues =
        getSession().getLogin().getPlatform().getConversionManager().getDefaultNullValues();
    getSession()
        .getLogin()
        .getPlatform()
        .getConversionManager()
        .setDefaultNullValues(new Hashtable());
    getSession().getLogin().setDefaultNullValue(String.class, "null");
    getSession().getLogin().setDefaultNullValue(int.class, new Integer(-1));
    // Reinit mappings.
    for (DatabaseMapping mapping : getSession().getDescriptor(Address.class).getMappings()) {
      if (mapping.isDirectToFieldMapping()) {
        mapping.preInitialize(getAbstractSession());
      }
    }
    getAbstractSession().beginTransaction();

    employee = new Employee();
    employee.setFirstName("Fred");
    employee.setLastName("Flintstone");
    employee.setSalary(22);
    employee.setGender("Male");
    Address address = new Address();
    address.setCity(null);
    employee.setAddress(address);

    getAbstractSession().writeObject(employee);
    // force the salary to be NULL
    getSession()
        .executeNonSelectingCall(
            new SQLCall("update SALARY set SALARY = null where EMP_ID = " + employee.getId()));
  }