code: public static byte[] sha1(byte[] data) {
          try {
              //Attempt to get a MessageDigest that uses SHA1
              MessageDigest md = MessageDigest.getInstance("SHA1");
              //Hash the data
              return md.digest(data);
          } catch (NoSuchAlgorithmException e) {
              //Alright, you might have an old system.
              throw new InternalError("SHA-1 is not supported on this platform - Outdated?");
          }
      }
docs: Performs a SHA-1 hash on the specified data
  
  @param data The data to hash
  @return The hashed data