Inheritance in java

 

 

inheritance, which is a form of software reuse in

which a new class is created by absorbing an existing class’s members and embellishing

them with new or modified capabilities. With inheritance, you can save time during program

development by basing new classes on existing proven and debugged high-quality

software. This also increases the likelihood that a system will be implemented and maintained

effectively.

When creating a class, rather than declaring completely new members, you can designate

that the new class should inherit the members of an existing class. The existing class

is called the superclass, and the newclass is the subclass. (The C++ programming language

refers to the superclass as the base class and the subclass as the derived class.) Each subclass

can become a superclass for future subclasses.

A subclass can add its own fields and methods. Therefore, a subclass is more specific

than its superclass and represents a more specialized group of objects. The subclass exhibits

the behaviors of its superclass and can modify those behaviors so that they operate appropriately

for the subclass. This is why inheritance is sometimes referred to as specialization.

The direct superclass is the superclass from which the subclass explicitly inherits. An

indirect superclass is any class above the direct superclass in the class hierarchy, which

defines the inheritance relationships between classes. In Java, the class hierarchy begins with

class Object (in package java.lang), which every class in Java directly or indirectly extends

(or “inherits from”).