求数组中所有几何对象的面积之和

eometricObject[] gobj = new GeometricObject[3];
        gobj[0] = new Triangle(new Point(1.0, 2.0), new Point(1.0, 1.0),
                new Point(0.0, 2.0));
        gobj[1] = new Circle(new Point(1.0, 2.0), 3);
        gobj[2] = new Rectangle(new Point(1.0, 2.0), new Point(1.0, 5.0),
                new Point(1.0, 0.0), new Point(5.0, 0.0));
        double sumArea = 0;
        for (int i = 0; i < gobj.length; i++) {
            if (gobj[i] != null) {
                double area = gobj[i].getArea();
                System.out.println(gobj[i].toString() + "其面积为:" + area);
                sumArea += area;
            }
        }
        System.out.println("总面积为：" + sumArea);

输出结果为：

三角形的三个顶点为:点(1.0,2.0);点(1.0,1.0);点(0.0,2.0);其面积为:0.5
圆形的中心为:点(1.0,2.0);半径为:3.0其面积为:28.27
矩形的四个顶点为:点(1.0,2.0);点(1.0,5.0);点(1.0,0.0);点(5.0,0.0);其面积为:6.0
总面积为：34.769999999999996