在 ScheduledExecutorService 上折腾了半天，先记下来。后面再补充其他线程池。
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ScheduledExecutorService
先是想当然地用了这个方法
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| public void testSchedule() {
ScheduledExecutorService executorService = Executors.newScheduledThreadPool(1);
System.out.println("start");
executorService.schedule(() -> {
System.out.println("1");
}, 2, TimeUnit.SECONDS);
try {
Thread.sleep(20000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("finish");
}
|
但是打印结果是：
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| start
1
finish
Process finished with exit code 0
|
只执行了一次，线程就结束了。这显然不是我想要的。想了一下，喔，schedule 只是一个定时执行，当然不会循环了……
然后点进去类里面，看到了这个方法
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| public void testScheduleAtFixedRate() {
ScheduledExecutorService executorService = Executors.newScheduledThreadPool(1);
System.out.println("start");
executorService.scheduleAtFixedRate(() -> {
System.out.println("1");
}, 2, 2, TimeUnit.SECONDS);
try {
Thread.sleep(20000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("finish");
}
|
打印结果是这样的：
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| start
1
1
1
1
1
1
1
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1
finish
1
Process finished with exit code 0
|
先这么用着吧。
