Instance methods

Instance methods on objects can access instance variables and .The method in the following sample is an example of aninstance method:

Getters and setters

With getters and setters, you can start with instance variables, laterwrapping them with methods, all without changing client code.

Abstract methods

Instance, getter, and setter methods can be abstract, defining aninterface but leaving its implementation up to other classes.Abstract methods can only exist in abstract classes.