Hierarchical Inheritance

Hierarchical inheritance in Java is a type of inheritance where multiple subclasses inherit from a single superclass. This type of inheritance allows a single class to serve as a base class for multiple derived classes, promoting code reuse and consistency across related classes.

Example of Hierarchical Inheritance in Java

Let's create an example with a superclass called Animal and three subclasses: Dog, Cat, and Bird. Each subclass will inherit from the Animal superclass and add specific behavior.
// Superclass
class Animal {
    String name;

    // Constructor
    Animal(String name) {
        this.name = name;
    }

    // Method to display the name
    void display() {
        System.out.println("Animal Name: " + name);
    }

    // Method to make a sound (to be overridden by subclasses)
    void sound() {
        System.out.println("Animal makes a sound");
    }
}

// Subclass Dog
class Dog extends Animal {

    // Constructor
    Dog(String name) {
        super(name);
    }

    // Override the sound method
    @Override
    void sound() {
        System.out.println("Dog barks");
    }
}

// Subclass Cat
class Cat extends Animal {

    // Constructor
    Cat(String name) {
        super(name);
    }

    // Override the sound method
    @Override
    void sound() {
        System.out.println("Cat meows");
    }
}

// Subclass Bird
class Bird extends Animal {

    // Constructor
    Bird(String name) {
        super(name);
    }

    // Override the sound method
    @Override
    void sound() {
        System.out.println("Bird chirps");
    }
}

// Main class to test the hierarchical inheritance
public class Main {
    public static void main(String[] args) {
        // Create instances of each subclass
        Dog dog = new Dog("Buddy");
        Cat cat = new Cat("Whiskers");
        Bird bird = new Bird("Tweety");

        // Display information and sounds for each animal
        dog.display();
        dog.sound();

        cat.display();
        cat.sound();

        bird.display();
        bird.sound();
    }
}

Program to Try

// Superclass
class Shape {
    // Method to display shape information
    void display() {
        System.out.println("This is a shape.");
    }

    // Abstract method to calculate the area (to be overridden by subclasses)
    double calculateArea() {
        return 0;
    }
}

// Subclass Rectangle
class Rectangle extends Shape {
    double length;
    double width;

    // Constructor
    Rectangle(double length, double width) {
        this.length = length;
        this.width = width;
    }

    // Override the calculateArea method
    @Override
    double calculateArea() {
        return length * width;
    }

    // Override the display method
    @Override
    void display() {
        System.out.println("This is a rectangle.");
    }
}

// Subclass Triangle
class Triangle extends Shape {
    double base;
    double height;

    // Constructor
    Triangle(double base, double height) {
        this.base = base;
        this.height = height;
    }

    // Override the calculateArea method
    @Override
    double calculateArea() {
        return 0.5 * base * height;
    }

    // Override the display method
    @Override
    void display() {
        System.out.println("This is a triangle.");
    }
}

// Subclass Circle
class Circle extends Shape {
    double radius;

    // Constructor
    Circle(double radius) {
        this.radius = radius;
    }

    // Override the calculateArea method
    @Override
    double calculateArea() {
        return Math.PI * radius * radius;
    }

    // Override the display method
    @Override
    void display() {
        System.out.println("This is a circle.");
    }
}

// Main class to test the hierarchical inheritance
public class Main {
    public static void main(String[] args) {
        // Create instances of each subclass
        Rectangle rectangle = new Rectangle(5, 3);
        Triangle triangle = new Triangle(4, 2.5);
        Circle circle = new Circle(2.5);

        // Display information and areas for each shape
        System.out.println("Rectangle:");
        rectangle.display();
        System.out.println("Area: " + rectangle.calculateArea());

        System.out.println("\nTriangle:");
        triangle.display();
        System.out.println("Area: " + triangle.calculateArea());

        System.out.println("\nCircle:");
        circle.display();
        System.out.println("Area: " + circle.calculateArea());
    }
}

Comments

Post a Comment

Popular posts from this blog

Introduction to Java Swing

Introduction to Java Swing Java Swing is a part of Java Foundation Classes (JFC) and provides a set of APIs for creating graphical user interfaces (GUIs) in Java. It is built on top of the Abstract Window Toolkit (AWT) and offers a richer set of GUI components. Swing is a platform-independent, lightweight toolkit that can be used to create window-based applications. Key Features of Swing Lightweight Components : Swing components are lightweight because they are written entirely in Java and do not rely on native platform components. Pluggable Look and Feel : Swing supports pluggable look and feel, which means you can change the appearance of your application to match different platforms (e.g., Windows, macOS, Linux) or create a custom look and feel. Component-based Architecture : Swing follows a component-based architecture, allowing for reusable, modular, and easily extendable components. MVC Architecture : Swing components follow the Model-View-Controller (MVC) design pattern, separa...
Read more

KTU OOP LAB JAVA CSL 203 BTech CS S3 - Dr Binu V P

About Me Scheme and Evaluation Syllabus and Practice Questions ******************************** How to do Java Programs in  Debian PART A Basic Java Programs Using Control  Statements 1.String Problems 2.Numerical Problems 3.Arrays 4.Matrix Lab Exercise Java-1 PART B  Object Oriented Programming 1.Creating classes and objects. constructor for initializing object 2.Method overloading in Java 3.Single Inheritance 4.Multilevel Inheritance 5.Method overriding in Java 6. Hierarchical Inheritance 7.Interface in Java 8.Abstract classes in java  PART C Exception and File Handling 1.Exception Handling in Java 2.Reading and Writing Text Files 3.Buffered Reader and String Tokenizer PART D Multi-Threading  Creating Threads in Java Thread Synchronization in Java Thread Priorities in Java Programs using Multi-Threading PART E Graphics and Database Programming Introduction to Java Swing Drawing Shapes Drawing  a Sine Wave Handling Mouse Events Handling Keyboard ...
Read more

JDBC Application Program

Write a program to accept rollno, name, CGPA of “n” students and store the data to a database using JDBC connectivity. Display the list of students having CGPA greater than 7. (Use MySQL /PostgreSQL). Steps: Set up MySQL Database : Ensure MySQL is running and create a database and table. Add MySQL Connector/J : Include the JDBC driver for MySQL in your project. Java Program : Write the Java program to interact with the database. 1. Set up MySQL Database Execute the following SQL commands to create a database and table: CREATE DATABASE studentdb; USE studentdb; CREATE TABLE students (     rollno INT PRIMARY KEY,     name VARCHAR(50),     cgpa FLOAT ); 2. Add MySQL Connector/J Dependency If you are using Gradle, add the following to your build.gradle implementation 'mysql:mysql-connector-java:8.0.33' 3.Java Program import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLExcept...
Read more