public static final String toString(byte[] ba, int offset, int length)
public static String toString(byte[] ba)
  public static final String toString(byte[] ba, int offset, int length)  {    char[] buf = new char[length * 2];    for (int i = 0, j = 0, k; i < length;)      {        k = ba[offset + i++];        buf[j++] = HEX_DIGITS[(k >>> 4) & 0x0F];        buf[j++] = HEX_DIGITS[k & 0x0F];      }    return new String(buf);  }