code: public void setLargeIcon(Icon icon) {
          Icon old = null;
          if (largeIconInfo == CommandButtonIconInfo.BLANK_ICON_INFO) {
              if (icon != null) {
                  // new IconInfo fires event
                  setLargeIconInfo(new CommandButtonIconInfo(icon));
              }
          }
          else {
              old = largeIconInfo.getIcon();
              this.largeIconInfo.setIcon(icon);
          }
          firePropertyChange(LARGE_ICON_PROPERTY, old, icon);
      }
docs: Sets the main default large icon for the command.
  
  @param icon The large icon. May be null.