Of this abstraction. The values for getRadius() or getCircumference() in the above mentioned illustration could be stored instantly, or they could be calculated, it isn't going to subject to the caller; the setters could possibly or may not have Uncomfortable side effects; it won't matter for the caller. @Jenix In https://propertyingurugram.in/work-on-gurugram-metro-to-start-soon-says-new-gmrl-md/