Introduction

Inheritance is a basic object oriented feature in which one class acquires and extends upon the properties of another class, using the keyword extends. For Interfaces and the keyword implements, see interfaces.

Syntax

• class ClassB extends ClassA {…}
• class ClassB implements InterfaceA {…}
• interface InterfaceB extends InterfaceA {…}
• class ClassB extends ClassA implements InterfaceC, InterfaceD {…}
• abstract class AbstractClassB extends ClassA {…}
• abstract class AbstractClassB extends AbstractClassA {…}
• abstract class AbstractClassB extends ClassA implements InterfaceC, InterfaceD {…}

Remarks

Inheritance is often combined with generics so that the base class has one or more type parameters. See Creating a Generic Class.

Inheritance

Implementing multiple interfaces

Abstract Classes

Declaring and Implementing an Interface

Using final to restrict inheritance and overriding

The Liskov Substitution Principle

Static Inheritance

Abstract class and Interface usage Is-a relation vs Has-a capability