Java Inheritance

What is Inheritance?

Inheritance allows one class to inherit properties and methods from another class. This helps reduce code duplication and models real-world relationships.

For example, a Dog is an Animal, so Dog can inherit common behavior from Animal.

Creating a Subclass

Use the extends keyword to create a subclass. The subclass automatically gets access to the parent class's public and protected members.

Using Inheritance

Once a class extends another, objects of the child class can use both its own methods and inherited methods from the parent class.

Method Overriding

A subclass can override a method from the parent class to provide its own implementation. Use @Override for clarity and error checking.

The super Keyword

The super keyword refers to the parent class. It is commonly used to call the parent constructor or access parent methods.

Inheritance Hierarchy

Java supports multi-level inheritance, where classes can extend other subclasses, forming a hierarchy.

Rules and Limitations

Java allows a class to extend only one class (single inheritance). Constructors are not inherited, and private members cannot be accessed directly.

• Only one parent class allowed
• Constructors are not inherited
• Private fields are not directly accessible

Practice

Create a Vehicle class and a Car subclass that overrides the start() method.

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