code: public void
  writeCountedString(byte [] s) {
  	if (s.length > 0xFF) {
  		throw new IllegalArgumentException("Invalid counted string");
  	}
  	need(1 + s.length);
  	array[pos++] = (byte)(s.length & 0xFF);
  	writeByteArray(s, 0, s.length);
  }
docs: Writes a counted string from the stream.  A counted string is a one byte
  value indicating string length, followed by bytes of data.
  @param s The string to write.