Question

用java编写矩形类上机题1：定义一个名为Rectangle矩形类，其数据成员为矩形的左下角和右上角两点的坐标，有计算矩

Answer 1

class Rectangle{

double x1, y1, x2, y2;

Rectangle(){

this(0,0,0,0);

}

Rectangle(double x1, double y1, double x2, double y2){

this.x1 = x1;

this.y1 = y1;

this.x2 = x2;

this.y2 = y2;

}

double getArea(){

return Math.abs((x1-x2)*(y1-y2))/2;

}

double getPemi(){

return Math.abs((x1-x2)+(y1-y2))*2;

}

}

public class Test{

public static void main(String[] args) {

Rectangle a = new Rectangle();

a.x1=2.1;

a.y1=3.2;

a.x2=5.2;

a.y2=6.3;

System.out.println("面积是"+a.getArea()+" 周长是"+a.getPemi());

Rectangle b = new Rectangle(1, 2, 6.8, 10.5);

System.out.println("面积是"+b.getArea()+" 周长是"+b.getPemi());

}

}