In the above instance code this.x/this.y refers to existing course that is definitely Place class x and y variables where by (double x,double y) are double values handed from distinct class to assign values to present-day course . This class isn't a direct subclass since the operations about the reference https://free-this-jav26037.onesmablog.com/new-step-by-step-map-for-jav-this-69114449