docs: public static String encodeZeroPadding(long number, int maxNumDigits) {
          String longString = Long.toString(number);
          int numZeroes = maxNumDigits - longString.length();
          StringBuffer strBuffer = new StringBuffer(numZeroes + longString.length());
          for (int i = 0; i < numZeroes; i++) {
              strBuffer.insert(i, '0');
          }
          strBuffer.append(longString);
          return strBuffer.toString();
      }