by Dinesh Thakur Category: Inheritance

In Our Example illustrates Multilevel Inheritance, Here Class B is derived from superclass A which itself acts as a superclass for the subclass C. The class C inherits the members of Class B directly as it is explicitly derived from it, whereas the members of class A are inherited indirectly into class c (via class B). So the class B acts as a direct superclass and A acts as a indirect superclass for class C.

 
by Dinesh Thakur Category: Inheritance

Inheritance is one the most powerful concepts in an object-oriented language. Through inheritance   the code developed for one class can be used in another class. That is, the data members made in a class can be used in another class. Inheritance is done by creating new classes that are extensions of other classes. The new class is known as a subclass. The original class is known as a superclass. The subclass has all the attributes of the superclass, and in addition has attributes that it defines itself. A class can have only one superclass. This is known as single inheritance. A superclass can have multiple subclasses.

 
by Dinesh Thakur Category: Inheritance

An interface is a way of describing what classes should do, without specifying how they should do it. A class can implement more than one interface. In Java, an interface is not a class but a set of requirements for the class that we want to conform to the interface. All the methods of an interface are by default public. So, it is not required to use the keyword public when declaring a method in an interface. Interfaces can also have more than one method. Interfaces can also define constants but do not implement methods. An interface is defined like a class. Its general form is:

 
by Dinesh Thakur Category: Inheritance

Inheritance is suitable only when classes are in a relationship in which subclass is a (kind of) superclass. For example: A Car is a Vehicle so the class Car has all the features of class Vehicle in addition to the features of its own class. However, we cannot always have. is a relationship between objects of different classes. For example: A car is not a kind of engine. To represent such a relationship, we have an alternative to inheritance known as composition. It is applied when classes are in a relationship in which subclass has a (part of) superclass.

 
by Dinesh Thakur Category: Inheritance

The class member attributes (fields) and methods are bounded with some accessibility modifier, which defines the access scope of the member. In this section, we'll study how to access the data members (attributes) of the class.

 
by Dinesh Thakur Category: Inheritance

As we know that in order to declare a variable that references an object, we use the following

syntax.

ClassName variableName;

Here, variableName is the name of the reference variable and ClassName is the name of its class. Thus, variablename can reference any object of class ClassName. However, it can also reference any object whose class is a subclass of ClassName. For example: If a class A is a superclass of class B and class B is a superclass of class C then in that case, variable of class A can reference any object derived from that class (i.e. object of class B and class c). This is possible because each subclass object is an object of its superclass but not vice versa.

 
by Dinesh Thakur Category: Inheritance

Java supports multilevel inheritance. In multiple, multilevel class hierarchies contain the layers of inheritance. But at each layer, a class is a subclass of the superc1ass of another, except the last layer. One pictorial representation of such concept is given below.

 
by Dinesh Thakur Category: Inheritance

Inheritance is one of the most dominant and vital feature of the object oriented programming because it supports the hierarchical classifications, reusability of class; and defined to specialization. Java is a language that supports inheritance but with some additional advantages and features.

 
by Dinesh Thakur Category: Inheritance

 For the reusability of existing classes, inheritance came into use, and java supports only two types of inheritance, in which a class extends another class.



 

Page 1 of 4

About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.



Search Content







Popular Article