protected static Map<String, String> appendParameters(
            Map<String, String> parameters, Map<String, String> appendParameters) {
        if (parameters == null) {
            parameters = new HashMap<>();
        }
        parameters.putAll(appendParameters);
        return parameters;
    }
@Test
    void appendParameter2() {
        Map<String, String> source = new HashMap<>();
        source.put("default.num", "one1");
        source.put("num", "ONE1");

        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"));
    }