Java eighth job - inherited

I, entitled

　　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)

Second, the source code

1.Rectangle class

/ ** rectangle class, a class with a long, wide two member variables and methods to find the circumference * / 
Package COM;
 public  class the Rectangle {
     Double A;
     Double B;
     Double C () {
         return 2 * A + 2 * B ; 
        
    } 
}

2.Square class

/ ** subclass of class rectangular - square classes, methods defined in the class seeking area, find the circumference rewriting process * / 
Package COM;
 public  class Square the extends the Rectangle {
     Double A;
     Double B;
     Double C () {
         return *. 4 A; 
        
    } 
    Double Area () {
         return A * A; 
        
    } 
}

3.Test class

/ * Main class, the input side length of a square, a square object is created, the square area and perimeter requirements and output * / 
Package COM;
 Import java.util.Scanner;
 public  class the Test { 

    / ** 
     * @param args
      * / 
    public  static  void main (String [] args) {
         // the TODO Auto-Generated Stub Method 
        System.out.println ( "enter a square side length:" ); 
        Scanner SC = new new Scanner (the System.in); 
        square sq. = new new Square (); 
        sq.a = sc.nextDouble (); 
        System.out.println ("Square area" + sq.area ()); 
        System.out.println ( "square circumference" + sq.C ()); 
    } 

}

Third, the operating results