javax.crypto.spec.SecretKeySpec;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest...hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
MessageDigest...messageDigest = MessageDigest.getInstance("SHA1");
messageDigest.update(StringToSign.getBytes...(UTF8));
byte[] md = messageDigest.digest();
int j = md.length;
char buf[] =