Writing Junit for mule java component class

I have a java mule component that implement Oncall method that accepts MuleEventContext as argument. I need to write Junit for this class; what is the best way to achieve this? My purpose is to write Junit for this component java class. What I have done is used mocked MuleEventContext and mule message class and added behavior for getpayload but not sure if that's the right way to write Junit in this case?