super() will be automatically inserted of this(…) or super(…) is not specified. If the super class does not include a no-arg constructor or it is not accessible, then it won’t compile. In that case it is necessary to put super(…) and specify the constructor .
Read moreHow can we call super in constructor?
To explicitly call the superclass constructor from the subclass constructor, we use super() . It’s a special form of the super keyword. super() can be used only inside the subclass constructor and must be the first statement.
Read more