Java 线程池详解学习：FixedThreadPool，CachedThreadPool，ScheduledThreadPool...

最新推荐文章于 2025-09-20 14:02:22 发布

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最新推荐文章于 2025-09-20 14:02:22 发布 · 963 阅读

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本文探讨了Java中两种常见的线程池实现：FixedThreadPool和CachedThreadPool，通过源码分析揭示了它们可能导致的资源耗尽风险，并引用阿里巴巴代码规范建议避免使用Executors创建线程池，推荐使用ThreadPoolExecutor来更好地控制线程池的行为。

Java常用的线程池有FixedThreadPool和CachedThreadPool，我们可以通过查看他们的源码来进行学习。

Java的源码下载参考这篇文章：Java源码下载和阅读（JDK1.8) - zhangpeterx的博客

在源码的目录java/util/concurrent下找到Executors.java文件查看源码。
里面提到的封装类有：
newScheduledThreadPool，newSingleThreadScheduledExecutor，newCachedThreadPool，newSingleThreadExecutor，newFixedThreadPool，newWorkStealingPool，newFixedThreadPool

我这里只把newFixedThreadPool，newCachedThreadPool的源码放出来：

public class Executors {
   
   

    /**
     * Creates a thread pool that reuses a fixed number of threads
     * operating off a shared unbounded queue.  At any point, at most
     * {@code nThreads} threads will be active processing tasks.
     * If additional tasks are submitted when all threads are active,
     * they will wait in the queue until a thread is available.
     * If any thread terminates due to a failure during execution
     * prior to shutdown, a new one will take its place if needed to
     * execute subsequent tasks.  The threads in the pool will exist
     * until it is explicitly {@link ExecutorService#shutdown shutdown}.
     *
     * @param nThreads the number of threads in the pool
     * @return the newly created thread pool
     * @throws IllegalArgumentException if {@code nThreads <= 0}
     */
    public static ExecutorService newFixedThreadPool(int nThreads) {