code: public boolean displayMessage (ChatMessage msg, boolean alreadyDisplayed)
      {
          // see if we're full, and if so, clear out a bunch of old stuff
          int adjusted;
          if (size() == MAX_HISTORY) {
              removeRange(0, PRUNE_HISTORY);
              adjusted = PRUNE_HISTORY;
  
          } else {
              adjusted = 0;
          }
  
          // add the message to the history
          add(msg);
  
          // notify observers that something changed
          notify(adjusted);
  
          return true;
      }
docs: documentation inherited from interface