源码：java.util.concurrent.ScheduledThreadPoolExecutor 源码解析

1. TODO

2. 脑图

  1. Xmind

  2. Edraw

  3. Hexo 地址
    👉 http://blog.wangjia.ink/2025/11/04/源码：java.util.concurrent.ScheduledThreadPoolExecutor源码解析/

3. 基础部分

3.1. ScheduledThreadPoolExecutor 概述

ScheduledThreadPoolExecutor 是一个具体类，继承了 java.util.concurrent.ThreadPoolExecutor，实现了 java.util.concurrent.ScheduledExecutorService

ScheduledThreadPoolExecutor 在 ThreadPoolExecutor 的基础上，只做了三件事：

  1. 使用 ScheduledThreadPoolExecutor.DelayedWorkQueue 作为任务队列
  2. 使用 ScheduledThreadPoolExecutor.ScheduledFutureTask 而不是 FutureTask

[!NOTE] 注意事项

  1. 详见源码：ThreadPoolExecutor
    1. obsidian 内部链接：
      1. 源码：java.util.concurrent.ThreadPoolExecutor源码解析
    2. Hexo 链接：
      1. http://blog.wangjia.ink/2025/09/03/源码：java.util.concurrent.ThreadPoolExecutor源码解析/
  2. 详见源码：ScheduledExecutorService
    1. obsidian 内部链接：
      1. 源码：java.util.concurrent.ScheduledExecutorService源码解析
    2. Hexo 链接：
      1. http://blog.wangjia.ink/2025/11/03/源码：java.util.concurrent.ScheduledExecutorService源码解析/

4. 内部类

4.1. DelayedWorkQueue

详见笔记：Java 数据类型

  1. obsidian 内部链接
    1. 笔记：Java数据类型
  2. Hexo 链接

4.2. ScheduledFutureTask

详见源码：ScheduledFutureTask＜V＞

  1. obsidian 内部链接：
    1. 源码：java.util.concurrent.ScheduledThreadPoolExecutor.ScheduledFutureTask＜V＞源码解析
  2. Hexo 链接：
    1. http://blog.wangjia.ink/2025/11/15/源码：java.util.concurrent.ScheduledThreadPoolExecutor.ScheduledFutureTask＜V＞源码解析/

5. 构造方法

5.1. ScheduledThreadPoolExecutor(int corePoolSize, ThreadFactory threadFactory, RejectedExecutionHandler handler)

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public ScheduledThreadPoolExecutor(int corePoolSize,
								   ThreadFactory threadFactory,
								   RejectedExecutionHandler handler) {
	super(corePoolSize, Integer.MAX_VALUE,
		  DEFAULT_KEEPALIVE_MILLIS, MILLISECONDS,
		  new DelayedWorkQueue(), threadFactory, handler);
}

[!NOTE] 注意事项

  1. DEFAULT_KEEPALIVE_MILLIS 是 ScheduledThreadPoolExecutor::DEFAULT_KEEPALIVE_MILLIS ，值为：10L

6. 实例方法

6.1. 实例具体方法

6.1.1. 具体方法（实现）

6.1.1.1. Executor 中接口方法的实现
6.1.1.1.1. void execute(Runnable command)
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public void execute(Runnable command) {
	
	schedule(command, 0, NANOSECONDS);
	
}
6.1.1.2. ExecutorService 中接口方法的实现
6.1.1.2.1. Future＜?＞ submit(Runnable task)
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public Future<?> submit(Runnable task) {
	
	return schedule(task, 0, NANOSECONDS);
	
}
6.1.1.2.2. ＜T＞ Future＜T＞ submit(Runnable task, T result)
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public <T> Future<T> submit(Runnable task, T result) {
	
	return schedule(Executors.callable(task, result), 0, NANOSECONDS);
	
}
6.1.1.2.3. ＜T＞ Future＜T＞ submit(Callable＜T＞ task)
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public <T> Future<T> submit(Callable<T> task) {
	
	return schedule(task, 0, NANOSECONDS);
	
}
6.1.1.3. ScheduledExecutorService 中接口方法的实现
6.1.1.3.1. ScheduledFuture＜?＞ schedule(Runnable comm, long delay, TimeUnit unit)
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public ScheduledFuture<?> schedule(Runnable command,
								   long delay,
								   TimeUnit unit) {
	
	if (command == null || unit == null)
		throw new NullPointerException();
		
	RunnableScheduledFuture<Void> t = decorateTask(command,
		new ScheduledFutureTask<Void>(command, null,
									  triggerTime(delay, unit),
									  sequencer.getAndIncrement()));
									  
	delayedExecute(t);
	
	return t;
	
}
6.1.1.3.2. ＜V＞ ScheduledFuture＜V＞ schedule(Callable＜V＞ callable, long delay, TimeUnit unit)
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public <V> ScheduledFuture<V> schedule(Callable<V> callable,
									   long delay,
									   TimeUnit unit) {
	if (callable == null || unit == null)
		throw new NullPointerException();
	RunnableScheduledFuture<V> t = decorateTask(callable,
		new ScheduledFutureTask<V>(callable,
								   triggerTime(delay, unit),
								   sequencer.getAndIncrement()));
	delayedExecute(t);
	return t;
}
6.1.1.3.3. ScheduledFuture＜?＞ scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit)
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public ScheduledFuture<?> scheduleAtFixedRate(Runnable command,
											  long initialDelay,
											  long period,
											  TimeUnit unit) {
	if (command == null || unit == null)
		throw new NullPointerException();
	if (period <= 0L)
		throw new IllegalArgumentException();
	ScheduledFutureTask<Void> sft =
		new ScheduledFutureTask<Void>(command,
									  null,
									  triggerTime(initialDelay, unit),
									  unit.toNanos(period),
									  sequencer.getAndIncrement());
	RunnableScheduledFuture<Void> t = decorateTask(command, sft);
	sft.outerTask = t;
	delayedExecute(t);
	return t;
}
6.1.1.3.4. ScheduledFuture＜?＞ scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit)
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public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command,
												 long initialDelay,
												 long delay,
												 TimeUnit unit) {
	if (command == null || unit == null)
		throw new NullPointerException();
	if (delay <= 0L)
		throw new IllegalArgumentException();
	ScheduledFutureTask<Void> sft =
		new ScheduledFutureTask<Void>(command,
									  null,
									  triggerTime(initialDelay, unit),
									  -unit.toNanos(delay),
									  sequencer.getAndIncrement());
	RunnableScheduledFuture<Void> t = decorateTask(command, sft);
	sft.outerTask = t;
	delayedExecute(t);
	return t;
}
源码
源码：java.util.concurrent.ScheduledThreadPoolExecutor 源码解析
https://wangjia5289.github.io/2025/11/04/源码：java.util.concurrent.ScheduledThreadPoolExecutor源码解析/
Author
咸阳猴🐒
Posted on
November 4, 2025
Licensed under