public static String[] delimitedListToStringArray(String str, String delimiter) {
        return delimitedListToStringArray(str, delimiter, null);
    }
@Test
    void testDelimitedListToStringArrayWithEmptyDelimiter() {
        String testCase = "a,b";
        String[] actual = StringUtils.delimitedListToStringArray(testCase, "", "");
        assertEquals(3, actual.length);
        assertEquals("a", actual[0]);
        assertEquals(",", actual[1]);
        assertEquals("b", actual[2]);
    }