Multiple classes in inheritance: – Reusability is yet another aspect of object oriented programming paradigm. It is always nice if we could reuse something that is already exists rather than creating the same all over again. Java support this concept. Java classes can be reused in several ways. This is basically done by creating new classes, reusing the property or existing one. The mechanism of deriving a new class from old one is called inheritance. The old class is known as the base class, supper class or parent class and new one class is called sub class, derived class or child class.

The inheritance allows sub classes to inherit all the variable and methods of their parent’s classes. In java, inheritance may take different forms. They are called single inheritance, multiple inheritance, hierarchical inheritance and multilevel inheritance.

Java does not directly implement multiple inheritance. However, this concept is implemented using a secondary inheritance path in the form of interface.