编写一个完整的Java Application 程序。包含接口ShapeArea，类Circle、Rectangle、Test。 ⑴接口ShapeArea

public class Test { public static void main(String[] args) { ShapeArea rectangle = new Rectangle(3, 4); ShapeArea circle = new Circle(2); System.out.println(rectangle.toString()); System.out.println(circle.toString()); } } interface ShapeA