@Test
void appendParameter() {

    Map<String, String> source = null;
    Map<String, String> parameters = new HashMap<>();
    parameters.put("default.num", "one");
    parameters.put("num", "ONE");
    source = AbstractBuilder.appendParameters(source, parameters);
    Assertions.assertTrue(source.containsKey("default.num"));
    Assertions.assertEquals("ONE", source.get("num"));
}