Inheritance

Question

Please i don't understand why the output of this code gives
/* New A
New B
*/

class A {
public A() {
System.out.println("New A");
}
}
class B extends A {
public B() {
System.out.println("New B");
}
}

class Program {
public static void main(String[ ] args) {
B obj = new B();
}
}

That's, I thought the would be /* New B */.

Answer 1

The super class constructor is invoked upon creation of the object.
Think of it as the compiler adding the super() keyword above everything in the class B constructor if it is not manually written.

Answer 2

B is a child of A, therefore to create B.
A MUST BE CREATED FIRST!

What happens when A gets created? You print New A
Then B gets created.
What happens when B gets created? You print New B

The result is New A New B.

Remember they have a parent child relationship. Children can't exist if parents don't make them.

Answer 3

OK thanks to you all. I got the understanding.