this and super

Package Day8; 

public  class Demo { 

    public  static  void main (String [] args) { 
        Son S = new new Son (); 
        s.print (); 
    } 

} 

class Father {
     int num1 = 10 ;
     int num2 = 20 is ; 
} 

class Son the extends father {
     int num2 = 30 ; // variables subclasses and superclasses best not to the same name, where for example using

     public  void Print () { 
        System.out.println (num1); // this class does not, call the parent class
        System.out.println (num2); // this class has, the principle of proximity 
        System.out.println ( Super .num2); // Super can call the parent class 
        System.out.println ( the this .num2); // the this the principle of proximity, both can call this class, you can call the parent class 
    }
 }

operation result: