Features and types of Inheritance in Java
Tags: java, programming, coding
Published: 2023-01-12 06:50:36

Inheritance is one of the core concepts in object-oriented programming (OOP) and is heavily used in Java. Inheritance allows one class to inherit properties and methods from another class, which can be used to create a hierarchy of classes. This article will explore the features and types of inheritance in Java. Inheritance is a fundamental concept in object-oriented programming (OOP). It allows you to define a new class that is based on an existing class. The new class inherits all of the properties and methods of the existing class, and can also add new properties and methods of its own. This allows you to reuse code, and also makes it easier to maintain and understand your codebase.

## Features of Inheritance in Java

**Code Reusability:** One of the main advantages of inheritance is the ability to reuse code. By inheriting from an existing class, a new class can take advantage of the functionality that is already defined in the parent class, thus reducing the amount of code that needs to be written.

**Method Overriding:** Inheritance allows subclasses to override methods of the parent class. This means that a subclass can change the implementation of a method inherited from the parent class to better suit its own needs.

**Access Control:** Inheritance in Java also provides access control. The properties and methods of a class can be marked as private, protected, or public, which determines their accessibility from other classes. A subclass can access the protected and public members of the parent class, but not the private members.

**Polymorphism:** Inheritance allows for polymorphism, which is the ability of an object to take on many forms. A variable of the parent class type can reference an object of a subclass type, and the program will call the overridden method of the subclass.

**Class Hierarchies:** Java allows you to create a hierarchy of classes, where one class inherits from another class, which in turn inherits from another class, and so on. This allows you to organize your code in a logical and meaningful way, and also makes it easier to understand and maintain your codebase.

**Ability to model the real world:** Inheritance allows you to model real world more effectively by relating entities, classes can inherit properties and methods of their superclass, and also they can have their own properties and methods.

**Abstraction:** Java allows you to create abstract classes and methods which means that a class or a method can be created without any implementation, this feature allows you to model real-world entities without providing the complete implementation details.

**Access Modifiers:** Java provides access modifiers like public, protected, default, and private which allow you to control the accessibility of properties and methods in superclass and subclass.

These are some of the main features and benefits of inheritance in Java. By utilizing inheritance, you can create a more flexible, organized, and maintainable codebase that can be easily extended and reused in the future.

## Types of Inheritance in Java

**Single Inheritance**

Single Inheritance in java occurs when a class inherits from only one parent class.

Single Inheritance is a type of inheritance where a class inherits properties and methods from only one class. It is the simplest form of inheritance in which a subclass inherits properties and methods from its immediate superclass, and can also have its own properties and methods. In [single inheritance](https://www.codingninjas.com/codestudio/library/single-inheritance-in-java), the subclass inherits all the properties and methods of the superclass and can use them as well as add new methods and properties of its own.

**Multiple Inheritance:** 

Multiple Inheritance in java is a type of inheritance in which a class inherits properties and methods from more than one class. This can be useful in situations where a class needs to inherit the properties and methods of multiple classes, in order to model a complex system or real-world scenario.
However, Java does not support multiple inheritance directly, meaning a class cannot inherit properties and methods from more than one class at a time. Java instead supports a concept called interface which allows a class to inherit properties and methods from multiple interfaces.

An interface is like a contract that a class can implement. An interface defines a set of method signatures but does not provide an implementation for any of the methods. A class that implements an interface must provide an implementation for all of the methods defined in the interface.

**Hybrid Inheritance:** 

Hybrid Inheritance in java is a combination of more than one type of inheritance, such as single inheritance, multi-level inheritance, and multiple inheritances. It is used when a class needs to inherit the properties and methods of multiple classes, and also multiple interfaces.
It can be thought of as a combination of different types of inheritances, combining the advantages of all of them. This allows you to create complex and sophisticated class hierarchies, and also to model real-world systems more effectively.

**Multilevel Inheritance:** 

Multilevel Inheritance in java is a type of inheritance where a class inherits from a class that itself inherits from another class. This creates a hierarchy of classes, with each subclass inheriting properties and methods from its immediate superclass, as well as from all of its superclass's superclasses. In multi-level inheritance, the subclass inherits all the properties and methods of its immediate superclass, as well as all the properties and methods of its superclass's superclass.

**Hierarchical Inheritance:** 

Hierarchical Inheritance in java is a type of inheritance in which a single class serves as the superclass for multiple subclasses. This allows for a more efficient way of reusing common properties and methods, as well as modeling real-world scenarios where a single class has multiple derivatives.
In Hierarchical Inheritance, a single class is inherited by more than one subclass. Each of these subclasses inherits the properties and methods of the superclass, but can also have their own properties and methods.

## Conclusion

Inheritance in Java is a powerful tool that allows developers to create a class hierarchy, reuse code, and support polymorphism. Understanding the features and types of inheritance can help you make the most of these capabilities when designing and implementing your Java programs.