code: public char getDataLength() {
  		char length = 0;
  
  		List<StunAttribute> attrs = getAttributes();
  		for (StunAttribute att : attrs) {
  			int attLen = att.getDataLength() + StunAttribute.HEADER_LENGTH;
  
  			// take attribute padding into account:
  			attLen += (4 - (attLen % 4)) % 4;
  
  			length += attLen;
  		}
  		return length;
  	}
docs: Returns the length of this message's body.
  
  @return the length of the data in this message.