Super is a reference to a direct superclass object. You can use super to access methods or properties in a parent class that are overridden by subclasses. Normal methods: There is no order limit, can be arbitrarily called. Constructor: in the constructor of any class where the first line of the constructor does not explicitly call super (…) So Java calls super () by default; As an initialization function for the parent class. All your super () here; It doesn’t matter whether you add it or not