计时器对象不是由垃圾收集器收集吗？

发布于 2025-02-05 02:41:21 字数 1135 浏览 1 评论 0原文

我尝试弄清以下代码：

    package com.company;
import java.util.Calendar;
import java.util.Timer;
import java.util.TimerTask;
public class Main {
    public static void main(String[] args) {
        Timer T = new Timer();
        TimerTask Birthday = new TimerTask(){
            int i = 5;
            @Override
            public void run(){
                if(i>0){
                    System.out.println(i);
                    i--;
                }
                else{
                    System.out.println("Happy Birthday John Doe");
                    T.cancel();
                }
            }
        };
        Calendar date = Calendar.getInstance();
        date.set(2021, Calendar.OCTOBER, 30,23, 59, 54);
       T.scheduleAtFixedRate(Birthday, date.getTime(), 1000);
    }
}

我很难理解以下行的工作原理：

t.cancel（）;

当 main 方法结束时，垃圾收集器是否收集了T（计时器）？毕竟运行 timertask 类的方法继续在 main 线程后继续运行，因此我假设计时器t 对象是由垃圾收集器收集的，并且在运行行 t.cancel（）时应出现运行时间异常。有人可以向我解释我看到的东西怎么了？

原文

I try to figure the following code:

    package com.company;
import java.util.Calendar;
import java.util.Timer;
import java.util.TimerTask;
public class Main {
    public static void main(String[] args) {
        Timer T = new Timer();
        TimerTask Birthday = new TimerTask(){
            int i = 5;
            @Override
            public void run(){
                if(i>0){
                    System.out.println(i);
                    i--;
                }
                else{
                    System.out.println("Happy Birthday John Doe");
                    T.cancel();
                }
            }
        };
        Calendar date = Calendar.getInstance();
        date.set(2021, Calendar.OCTOBER, 30,23, 59, 54);
       T.scheduleAtFixedRate(Birthday, date.getTime(), 1000);
    }
}

I have difficult to understand how the following line works:

T.cancel();

Isn't T (Timer) was collected by garbage collector when the main method ends?
After all the run method of TimerTask class continue to run after main thread was close and therefore i assume that Timer T object was collected by garbage collector and when running the row T.cancel() a run time exception should appear.
Can someone explain me what is wrong with the way i see the things?