package demo;

public class Tongji {
    private static int n;
    public Tongji()
    {
        n++;//次new一個物件的時候都可以給n加1
    }
    public static int getNum()
    {
        return n;//返回n值
    }
    public static void main(String[] args) {
        // TODO 自動生成的方法存根
        Tongji t1=new Tongji();
        Tongji t2
 
=new Tongji();
        Tongji t3=new Tongji();//建立物件
        System.out.println("共有物件個數為："+Tongji.getNum());
    }

}