public static boolean containsHexPrefix(String input) {
        return !Strings.isEmpty(input)
                && input.length() > 1
                && input.charAt(0) == '0'
                && input.charAt(1) == 'x';
    }
@Test
    public void testHandleNPE() {
        assertFalse(Numeric.containsHexPrefix(null));
        assertFalse(Numeric.containsHexPrefix(""));
    }