code: public JButton add(Action act)
  	{
  		JButton _button;
  		_button = super.add(act);
  		_button.setRequestFocusEnabled(false);
  		if (null != act.getValue(Action.SMALL_ICON))
  		{
  			_button.setToolTipText((String) act.getValue(Action.NAME));
  			_button.setText(null);
  		}
  		return _button;
  	}
docs: Add the action and setup the obtained button to behave correctly and further settings (icon, tooltip, focus).
  
  @see javax.swing.JToolBar#add(javax.swing.Action)