1 package com.bytezreo.statictest; 2 3 /** 4 * 5 * @Description static 关键字的使用 小练习 6 * @author Bytezero·zhenglei! Email:420498246@qq.com 7 * @version 8 * @date 下午12:51:45 9 * @ 10 * 11 */ 12 public class CircleTest 13 { 14 public static void main(String[] args) 15 { 16 Circle c1 = new Circle(); 17 18 Circle c2 = new Circle(); 19 20 Circle c3 = new Circle(); 21 System.out.println("c1的id:"+c1.getId()); 22 System.out.println("c2的id:"+c2.getId()); 23 System.out.println("c3的id:"+c3.getId()); 24 25 System.out.println("创建圆的个数为:"+Circle.getTotal()); 26 27 28 } 29 } 30 31 class Circle 32 { 33 private double radius; 34 private int id; //自动赋值 35 36 //构造器 37 public Circle() 38 { 39 id = init++; 40 total++; 41 } 42 43 public Circle(double radius) 44 { 45 this(); 46 // id = init++; //自动累加id 47 // total++; 48 49 this.radius = radius; 50 51 } 52 53 54 55 private static int total; //记录创建圆的个数 56 private static int init = 1001; //静态 多个对象共享 57 58 public double findArea() 59 { 60 return 3.14 * radius * radius; 61 } 62 63 public double getRadius() { 64 return radius; 65 } 66 67 public void setRadius(double radius) { 68 this.radius = radius; 69 } 70 71 public int getId() { 72 return id; 73 } 74 75 public static int getTotal() { 76 return total; 77 } 78 79 80 81 82 83 84 85 }