public static byte[] chars2Bytes(final char[] chars) {
        if (chars == null || chars.length <= 0) return null;
        int    len   = chars.length;
        byte[] bytes = new byte[len];
        for (int i = 0; i < len; i++) {
            bytes[i] = (byte) (chars[i]);
        }
        return bytes;
    }
@Test
    public void chars2Bytes() throws Exception {
        TestCase.assertTrue(
                Arrays.equals(
                        mBytes1,
                        ConvertKit.chars2Bytes(mChars1)
                )
        );
    }