public ApplicationBuilder appendParameters(Map<String, String> appendParameters) {
        this.parameters = appendParameters(parameters, appendParameters);
        return getThis();
    }
@Test
    void appendParameters() {
        Map<String, String> source = new HashMap<>();
        source.put("default.num", "one");
        source.put("num", "ONE");

        ApplicationBuilder builder = new ApplicationBuilder();
        builder.appendParameters(source);

        Map<String, String> parameters = builder.build().getParameters();

        Assertions.assertTrue(parameters.containsKey("default.num"));
        Assertions.assertEquals("ONE", parameters.get("num"));
    }