What defines the design of all classes?

There are three ways to design classes: by composition, via inheritance, and via interface . Composition (or aggregation) is achieved by using existing class as a part of a new class. For example, the ArrayStack class includes an array of objects. Inheritance allows you to define a new class in terms of an old class.

Read more

What does a class consist of?

a class describes the contents of the objects that belong to it: it describes an aggregate of data fields (called instance variables), and defines the operations (called methods) . object: an object is an element (or instance) of a class; objects have the behaviors of their class.

Read more

What does a class contains in Java?

A class describes the data and the methods of its objects . Every object belongs to some class. An object contains data (instance variables) representing its state, and instance methods, which are the things it can do. A class may also contain its own data (class variables) and class methods.

Read more