java eighth job - inherited

Title : writing an application, create a rectangle class, a class with a long, wide two member variables and methods find the circumference. Then create a subclass of the class of rectangular - square classes, methods defined in the class seeking area, find the circumference rewriting method. In the main class, the input side length of a square, a square object is created, the square area and perimeter requirements. (Note: all classes are in a package)

Code

/ ** 
 * There are three categories, three methods 
 * Rect rectangle is based, variable three members are a, b, sum representing the length, width, perimeter, a method GetSum () find the circumference rectangular 
 * Square is square type, two member variables, to calculate the perimeter of a method override, a new definition of the method for calculating the area; 
 * method, is the main class, area and perimeter squares method calls calculates and outputs; 
 * / 
Package U;
 Import Java. * util. ;
    class Rect {
       public  Double A;
       public  Double B;
       public  Double SUM;
        public  Double GetSum () { 
           SUM = (A + B) * 2 ;
            return SUM; 
       } 
   } 
   class Square the extends Rect {     // inherited 
      
       public  Double the getArea () { 
          
          return A * A; 
       } 
       public  Double GetSum () {    // perimeter overridden methods 
           return A *. 4 ; 
       } 
   } 
   
public  class Method, {
     public  static  void main (String [] args) { 
        System.out.println ( "Please enter the side length of the square:" ); 
        Scanner Reader = new new Scanner (the System.in); 
        square SC = new new square (); 
        sc.a = reader.nextDouble ();
        System.out.println ( "area of the square is:" + sc.getSum ()); // call to the subclass method 
        System.out.println ( "square perimeter is:" + sc.getArea ()); 
    } 
}

Operation result