code: public void drawMessageCompleted(GenericTabItem tab, TraceCPU cpu,  TraceThread thread, TraceBus bus, TraceOperation op, TraceObject obj)
  	{
  		updateObject(tab, obj);
  		Long busX = bus.getX();
  		String toolTipLabel = op.getName();
  		Long objX = obj.getX();
  		
  		//Draw Bus Marker
  		drawMarker(tab, busX, tab.getYMax(), busX, tab.getYMax() + ELEMENT_SIZE, ColorConstants.darkGray);	
  		
  		//Draw Message Arrow
  		drawHorizontalArrow(tab, busX + BUSMSG_ARROW_OFFSET, objX - BUSMSG_ARROW_OFFSET, tab.getYMax(), " " , toolTipLabel, ColorConstants.darkGreen);
  	}
docs: Bus Messages