一只后端汪

ThreadPoolExecutor 源码

The main pool control state

属性 ctl 用来表示表示他内部的两个状态：工作线程数（workerCount），运行状态（runState）：

/**
 * The main pool control state, ctl, is an atomic integer packing
 * two conceptual fields
 *   workerCount, indicating the effective number of threads
 *   runState,    indicating whether running, shutting down etc
 */
 private final AtomicInteger ctl = new AtomicInteger(ctlOf(RUNNING, 0));