Tomcat 在启动EndPoint组件的时候，会创建一个线程池

public void createExecutor() {
        internalExecutor = true;
		//任务队列
        TaskQueue taskqueue = new TaskQueue();
        TaskThreadFactory tf = new TaskThreadFactory(getName() + "-exec-", daemon, getThreadPriority());
        executor = new ThreadPoolExecutor(getMinSpareThreads(), getMaxThreads(), 60, TimeUnit.SECONDS,taskqueue, tf);
        taskqueue.setParent( (ThreadPoolExecutor) executor);
    }
	//此时的ThreadPoolExecutor不是Java里ThreadPoolExecutor,是Tomcat新建了一个同名的类继承了java里的线程池类
	public ThreadPoolExecutor(int corePoolSize, int maximumPoolSize, long keepAliveTime, TimeUnit unit, BlockingQueue<Runnable> workQueue, ThreadFactory threadFactory) {
	   //new一下
        super(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue, threadFactory, new RejectHandler());
		//启动所有核心线程
        prestartAllCoreThreads();
    }

ThreadPoolExecutor

 public ThreadPoolExecutor(int corePoolSize,
                              int maximumPoolSize,
                              long keepAliveTime,
                              TimeUnit unit,
                              BlockingQueue<Runnable> workQueue,
                              ThreadFactory threadFactory,
                              RejectedExecutionHandler handler) {
        if (corePoolSize < 0 ||
            maximumPoolSize <= 0 ||
            maximumPoolSize < corePoolSize ||
            keepAliveTime < 0)
            throw new IllegalArgumentException();
        if (workQueue == null || threadFactory == null || handler == null)
            throw new NullPointerException();
        this.acc = System.getSecurityManager() == null ?
                null :
                AccessController.getContext();
        this.corePoolSize = corePoolSize;
        this.maximumPoolSize = maximumPoolSize;
        this.workQueue = workQueue;
        this.keepAliveTime = unit.toNanos(keepAliveTime);
        this.threadFactory = threadFactory;
        this.handler = handler;
    }

TaskQueue

//TaskQueue是Tomcat自己实现的一个队列
//LinkedBlockingQueue 是java体系的 作者Doug Lea
public class TaskQueue extends LinkedBlockingQueue<Runnable> {
}

接下来的篇章会沿着这两条线索去分析

• 线程池原理
• 线程原理
• Linux任务调度
• Java锁机制
• Linux锁机制
• 并发容器处理逻辑

下一章从最简单的线程池开始