public static Properties loadProperties(Set<ClassLoader> classLoaders, String fileName) {
        return loadProperties(classLoaders, fileName, false, false);
    }
@Test
    void testLoadPropertiesNoFile() throws Exception {
        Properties p = ConfigUtils.loadProperties(Collections.emptySet(), "notExisted", true);
        Properties expected = new Properties();
        assertEquals(expected, p);

        p = ConfigUtils.loadProperties(Collections.emptySet(), "notExisted", false);
        assertEquals(expected, p);
    }