}

    @Override
    protected void tearDown(TestInfo testInfo) throws Exception {
        super.tearDown(testInfo);
    }

    // Test append method with null value
    @Test
    public void test_append_nullValue() {
        StringBuilder buf = new StringBuilder();
        Supplier<Object> supplier = () -> null;

        monitorTarget.append(buf, "testKey", supplier);
        assertEquals("\"testKey\":null", buf.toString());