public static String encode(String packet) {
    StringBuilder buffer = new StringBuilder(packet.length());
    for (int i = 0; i < packet.length(); i++) {
      char chr = packet.charAt(i);
      if (chr == ourSpecialSymbol) {
        buffer.append(chr);
        buffer.append(chr);
        continue;
      }
      boolean appendChar = true;
      for (char c : ourSymbolsToEncode) {
        if (c == chr) {
          buffer.append(ourSpecialSymbol);
          final String code = String.valueOf((int)chr);
          for (int count = CODE_LENGTH - code.length(); count > 0; count--) {
            buffer.append("0");
          }
          buffer.append(code);
          appendChar = false;
          break;
        }
      }
      if (appendChar) {
        buffer.append(chr);
      }
    }
    return buffer.toString();
  }
public static String encode(String packet)