def init(cls, typ, class2type):
        """
        Defines custom fields in the value factory so that the importer can find them
        @param typ
        @param class2type
        """
        field = typ.getField(cls.FIELD_NAME)
        class2type.put( StrStrHashMap , typ )
        typ.setComponentType( StrStrHashMap )
        typ.setImportExportHelper( StrStrHashMapSerializer(typ, field))
        typ.putValidator(field, Validator_object.get(1))
        typ.lock()
def test_subclass(self):
        class X(Structure):
            _fields_ = [("a", c_int)]

        class Y(X):
            _fields_ = [("b", c_int)]

        class Z(X):
            pass

        self.assertEqual(sizeof(X), sizeof(c_int))
        self.assertEqual(sizeof(Y), sizeof(c_int)*2)
        self.assertEqual(sizeof(Z), sizeof(c_int))
        self.assertEqual(X._fields_, [("a", c_int)])
        self.assertEqual(Y._fields_, [("b", c_int)])
        self.assertEqual(Z._fields_, [("a", c_int)])