code: protected void onAttributeChanged(String name) {
  		Object v = null;
  		try {
  			v = getAttribute(name).getValue();
  		} catch (Exception exception) {
  			//
  		}
  		if (ATTR_COLOR.equalsIgnoreCase(name)) {
  			fireGraphicalAttributeChanged(name, null, v);
  		} else {
  			firePrimitiveChanged(name, null, v);
  		}
  	}
docs: This function is invoked by the attribute provider each time
  an attribute has changed.
  
  <p>You should override this method to provide several feedback
  to the BusPrimitive for instance.
  
  @param name is the name of the attribute that changed