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 get_date(self, p_tag):
        """ Given a date tag, return a date object. """
        string = self.tag_value(p_tag)
        result = None

        try:
            result = date_string_to_date(string) if string else None
        except ValueError:
            pass

        return result