//使用类的静态字段和构造函数,可以跟踪某个类所创建对象的个数。
1 package demo;
2
3 //import java.util.Scanner;
4
5 public class Num_Obj {
6
7
8 static private int num = 0;
9
10 Num_Obj()
11 {
12 num ++ ;
13 }
14
15 public int getNum() {
16 return num;
17 }
18
19
20
21 public static void main(String[] args) {
22 // TODO Auto-generated method stub
23
24 Num_Obj o1 = new Num_Obj();
25 System.out.println("创建的第" + o1.getNum() + "个对象");
26
27
28 for(int k = 0; k < 10; k++)
29 {
30 Num_Obj obj= new Num_Obj();
31 //obj = new Num_Obj();
32 System.out.println("创建对象个数:" + obj.getNum());
33 }
34
35 }
36
37 }