code: public void addDisplay(String displayID, Display3D display)
              throws ShanksException {
          Scenario3DPortrayal scenarioPortrayal = (Scenario3DPortrayal) this
                  .getSimulation().getScenarioPortrayal();
          HashMap<String, Display3D> displays = scenarioPortrayal.getDisplays();
          if (!displays.containsKey(displayID)) {
              displays.put(displayID, display);
          } else {
              throw new DuplictaedDisplayIDException(displayID);
          }
      }
docs: Add a display to the simulation
  
  @param displayID
  @param display
  @throws DuplictaedDisplayIDException
  @throws DuplicatedPortrayalIDException
  @throws ScenarioNotFoundException