Why should I call super() in Java?

Question

I see an example from a book that I read about java:

public class A{
  public A(){
      System.out.println(\"A\");
   }
}

public class B extends A{
    public          


        

Answer 1

In this particular case, you don't need to call super();, because Java will insert the call to super(); implicitly in a constructor if you don't explicitly call it. (Java Tutorial link).

It only becomes necessary in other cases, in which you want to call another, non-default constructor in the superclass, such as this:

public class A{
  public A(String s){
      System.out.println("A");
   }
}

public class B extends A{
    public B(String s){
       super(s);
       System.out.println("B");
   }
}