Constructor Overloading and overriding in JAVA

In Java, constructors are special methods that are used to create objects of a class. Like regular methods, constructors can be overloaded and overridden. Here’s a brief explanation of constructor overloading and overriding in Java:

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Constructor Overloading: Constructor overloading is the process of creating multiple constructors in a class, each with a different set of parameters. It’s useful when you want to create objects of a class with different sets of initial values.

For example, suppose you have a class called Rectangle that represents a rectangle with a given length and width. You could create multiple constructors for the Rectangle class that take different sets of parameters, such as:

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public class Rectangle {
    private int length;
    private int width;

    public Rectangle() {
        this.length = 0;
        this.width = 0;
    }

    public Rectangle(int length, int width) {
        this.length = length;
        this.width = width;
    }

    public Rectangle(int length) {
        this.length = length;
        this.width = 0;
    }
}

In this example, we have created three constructors for the Rectangle class. The first constructor initializes the length and width fields to 0. The second constructor takes two parameters and initializes the length and width fields to the values of those parameters. The third constructor takes one parameter and initializes the length field to the value of that parameter and the width field to 0.

Constructor Overriding: Constructor overriding is not possible in Java, as constructors are not inherited like regular methods. However, a subclass can call a constructor of its superclass using the super() keyword.

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For example, suppose you have a subclass called Square that extends the Rectangle class and represents a square with a given side length. You could create a constructor for the Square class that calls the constructor of its superclass, Rectangle, using the super() keyword, like this:

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public class Square extends Rectangle {
    public Square(int sideLength) {
        super(sideLength, sideLength);
    }
}

In this example, we have created a constructor for the Square class that takes one parameter, sideLength, and calls the constructor of its superclass, Rectangle, using the super() keyword. The super() call initializes the length and width fields of the Square object to the same value, which creates a square object.