public class StudentTest {public static void main(String[] args) {Student[] stus new Student[20]; //声明Student类型的数组(这只是创建数组,因为是引用数据类型(只能存放null或者地址),还没创建对象࿰…
public class Circle {double radius;//半径//求圆的面积public double findArea(){return Math.PI*radius*radius;}
}
public class PassObject {public static void main(String[] args) {PassObject p1new PassObject();Circle c1 new Circle();p1.printAreas(c1,5);System…