public static String toString(InputStream input, String encoding) throws IOException {
        return (null == encoding) ? toString(new InputStreamReader(input, Constants.ENCODE))
                : toString(new InputStreamReader(input, encoding));
    }
@Test
    void testToStringV1() {
        
        try {
            InputStream input = IOUtils.toInputStream("test", StandardCharsets.UTF_8);
            String actualValue = MD5Util.toString(input, "UTF-8");
            assertEquals("test", actualValue);
        } catch (IOException e) {
            System.out.println(e.toString());
        }
    }