protected boolean hasOnlyFields(String... allowedFields) {
        return hasOnlyFields(object, allowedFields);
    }
@Test
    public void hasOnlyFields() {
        assertTrue("has unexpected fields",
                cfg.hasOnlyFields(TEXT, LONG, DOUBLE, BOOLEAN, MAC, BAD_MAC,
                        IP, BAD_IP, PREFIX, BAD_PREFIX,
                        CONNECT_POINT, BAD_CONNECT_POINT, TP_PORT, BAD_TP_PORT));
        assertTrue("did not detect unexpected fields",
                expectInvalidField(() -> cfg.hasOnlyFields(TEXT, LONG, DOUBLE, MAC)));
    }