Java Program to Show Inherited Constructor Calls Parent Constructor By Default

In java, there exists a very important keyword known as super() keyword in java which is widely used in java being object-oriented and hence inheritance comes into play. So whenever we use super keyword inside a child constructor then it calls the default parent constructor by itself.

Example 1

Java

// Java Program to Demonstrate Inherited constructor
// calls the parent constructor by default

// Class 1
// Main class
class GFG {
    public static void main(String[] a)
    {
        // Inherited constructor calling
        new child();
        new parent();
    }
}

// Class 2
// Parent class - Helper class
class parent {

    // Constructor of parent class
    parent()
    {
        System.out.println("I am parent class constructor");
    }
}

// Class 3
// Child class - Helper class
class child extends parent {

    // Constructor of child class
    child()
    {
        System.out.println("I am child class constructor");
    }
}

Output

I am parent class constructor
I am child class constructor
I am parent class constructor

Example 2

Java

// Java Program to Demonstrate Inherited constructor
// calls the parent constructor by default

// Class 1
// Main class
class GFG {

    // Main driver method
    public static void main(String[] a)
    {
        // Inherited constructor calling
        new child();
        new child(100);
    }
}

// Class 2
// Parent class (Helper class)
class parent {

    // Constructor of parent class
    parent()
    {
        // Print statement
        System.out.println("I am parent class constructor");
    }
}

// Class 3
// Child class (Helper class)
class child extends parent {

    // Constructor 1
    // Constructor of child class
    child()
    {
        // Print statement
        System.out.println("I am child class constructor");
    }

    // Constructor 2
    // Constructor of child class
    child(int x)
    {
        // Print statement
        System.out.println(
            "I am param child class constructor");
    }
}

Output

I am parent class constructor
I am child class constructor
I am parent class constructor
I am param child class constructor