2. 程式人生 > >和朱曄一起復習Java併發（一）：執行緒池

和朱曄一起復習Java併發（一）：執行緒池

阿新 • • 發佈：2019-07-14

和我之前的Spring系列文章一樣，我們會以做一些Demo做實驗的方式來複習一些知識點。
本文我們先從Java併發中最最常用的執行緒池開始。

從一個執行緒池實驗開始

首先我們寫一個方法來每秒一次定時輸出執行緒池的基本資訊：

private void printStats(ThreadPoolExecutor threadPool){
    Executors.newSingleThreadScheduledExecutor().scheduleAtFixedRate(() -> {
        log.info("=========================");
        log.info("Pool Size: {}", threadPool.getPoolSize());
        log.info("Active Threads: {}", threadPool.getActiveCount());
        log.info("Number of Tasks Completed: {}", threadPool.getCompletedTaskCount());
        log.info("Number of Tasks in Queue: {}", threadPool.getQueue().size());

        log.info("=========================");
    }, 0, 1, TimeUnit.SECONDS);
}

然後，我們寫一個方法來定時提交任務到執行緒池：

private void submitTasks(AtomicInteger atomicInteger, ThreadPoolExecutor threadPool) {
    IntStream.rangeClosed(1, 20).forEach(i -> {
        try {
            TimeUnit.SECONDS.sleep(1);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        int id = atomicInteger.incrementAndGet();
        threadPool.submit(() -> {
            log.info("{} started", id);
            try {
                TimeUnit.SECONDS.sleep(10);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            log.info("{} finished", id);
        });
    });
}

可以看到：

  • 一共提交20個任務
  • 每秒提交一個任務
  • 每一個任務執行耗時10秒
  • 任務內容很簡單，就是計數器累加

現在我們寫一個最普通的執行緒池，並且等待執行緒池所有任務執行完成：

@Test
public void test1() throws InterruptedException {
    AtomicInteger atomicInteger = new AtomicInteger();
    ThreadPoolExecutor threadPool = new ThreadPoolExecutor(
            2, 5,
            5, TimeUnit.SECONDS,
            new ArrayBlockingQueue<>(10));

    printStats(threadPool);
    submitTasks(atomicInteger,threadPool);
    threadPool.shutdown();
    threadPool.awaitTermination(1, TimeUnit.HOURS);
}

可以看到，這個執行緒池是：

  • 2個核心執行緒
  • 5個最大執行緒
  • 5秒回收限制（最大）執行緒
  • 佇列最多10個任務

對於這樣的配置，大家想一下，任務提交過去後，執行緒池的工作方式是怎麼樣的？丟擲幾個問題：

  • 一開始執行緒池會有多少執行緒？
  • 慢慢的執行緒池的執行緒會變為多少？
  • 這些任務是否能執行完成？

我們執行後觀察一下輸出：

09:51:37.709 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:37.715 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 0
09:51:37.718 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 0
09:51:37.718 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:37.718 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 0
09:51:37.718 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:38.705 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:38.705 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 0
09:51:38.705 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 0
09:51:38.705 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:38.705 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 0
09:51:38.705 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:38.716 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 1 started
09:51:39.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:39.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 1
09:51:39.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 1
09:51:39.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:39.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 0
09:51:39.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:39.718 [pool-1-thread-2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 2 started
09:51:40.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:40.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:40.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:40.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:40.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 0
09:51:40.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:41.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:41.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:41.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:41.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:41.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 1
09:51:41.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:42.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:42.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:42.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:42.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:42.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 2
09:51:42.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:43.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:43.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:43.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:43.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:43.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 3
09:51:43.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:44.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:44.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:44.701 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:44.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:44.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 4
09:51:44.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:45.702 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:45.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:45.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:45.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:45.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 5
09:51:45.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:46.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:46.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:46.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:46.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:46.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 6
09:51:46.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:47.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:47.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:47.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:47.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:47.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 7
09:51:47.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:48.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:48.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:48.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:48.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
09:51:48.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 8
09:51:48.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:48.719 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 1 finished
09:51:48.719 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 3 started
09:51:49.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:49.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:49.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:49.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 1
09:51:49.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 8
09:51:49.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:49.720 [pool-1-thread-2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 2 finished
09:51:49.720 [pool-1-thread-2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 4 started
09:51:50.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:50.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:50.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:50.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
09:51:50.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 8
09:51:50.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:51.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:51.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:51.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:51.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
09:51:51.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 9
09:51:51.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:52.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:52.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
09:51:52.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
09:51:52.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
09:51:52.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 10
09:51:52.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:52.749 [pool-1-thread-3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 15 started
09:51:53.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:53.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 3
09:51:53.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 3
09:51:53.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
09:51:53.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 10
09:51:53.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:53.754 [pool-1-thread-4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 16 started
09:51:54.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:54.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 4
09:51:54.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 4
09:51:54.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
09:51:54.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 10
09:51:54.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:54.755 [pool-1-thread-5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 17 started
09:51:55.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
09:51:55.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
09:51:55.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
09:51:55.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
09:51:55.703 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in queue: 10
09:51:55.704 [pool-2-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================

java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.FutureTask@fdefd3f[Not completed, task = java.util.concurrent.Executors$RunnableAdapter@1a0dcaa[Wrapped task = me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest$$Lambda$50/0x0000000800105840@3bd40a57]] rejected from java.util.concurrent.ThreadPoolExecutor@d83da2e[Running, pool size = 5, active threads = 5, queued tasks = 10, completed tasks = 2]

    at java.base/java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution(ThreadPoolExecutor.java:2055)
    at java.base/java.util.concurrent.ThreadPoolExecutor.reject(ThreadPoolExecutor.java:825)
    at java.base/java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1355)
    at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:118)
    at me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest.lambda$submitTasks$2(ThreadPoolExecutorTest.java:33)
    at java.base/java.util.stream.Streams$RangeIntSpliterator.forEachRemaining(Streams.java:104)
    at java.base/java.util.stream.IntPipeline$Head.forEach(IntPipeline.java:593)
    at me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest.submitTasks(ThreadPoolExecutorTest.java:26)
    at me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest.test1(ThreadPoolExecutorTest.java:54)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

通過輸出可以看到：

  • 雖然配置了2個核心執行緒，但是一開始執行緒池還是0個執行緒，你可以通過threadPool.prestartAllCoreThreads()來改變這個行為，初始化所有的核心執行緒
  • 隨著任務的提交，核心執行緒慢慢初始化，一直到2個核心執行緒
  • 因為任務執行需要10s，所以慢慢佇列裡面會堆積任務，任務慢慢堆積到10
  • 然後執行緒池會繼續新增執行緒，一直到最大執行緒數5
  • 到了最大執行緒數5的情況下，佇列也是打到了10滿了，這個時候還有任務進來就會出現拒絕執行的異常

我們知道，Java的執行緒池預設情況下是更傾向於使用佇列來存放任務而不是傾向於使用更多的執行緒來消化任務，只有當佇列滿了之後才會使用更多的執行緒池臨時處理一下突發的任務增多。
有的時候，我們其實更希望的是更激進的方式，執行緒池優先開啟更多的執行緒，而是把隊列當成一個後備方案來使用。比如我們這個例子，任務執行的很慢，需要10s，每秒提交一個任務，如果執行緒池可以彈性到5個最大執行緒，那麼20秒後有5個任務在執行，5個任務已經完成，還有10個線上程池裡，這些任務最終都可以完成，而不是像之前因為執行緒池過晚擴張導致慢任務來不及處理。

我們可以通過Hack的方式來實現：

@Test
public void test2() throws InterruptedException {
    AtomicInteger atomicInteger = new AtomicInteger();

    BlockingQueue<Runnable> queue = new LinkedBlockingQueue<>(10) {
        @Override
        public boolean offer(Runnable e) {
            return false;
        }
    };

    ThreadPoolExecutor threadPool = new ThreadPoolExecutor(
            2, 5,
            5, TimeUnit.SECONDS,
            queue, new ThreadFactoryImpl("elastic-pool"), (r, executor) -> {
        try {
            executor.getQueue().put(r);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        }
    });

    threadPool.allowCoreThreadTimeOut(true);
    printStats(threadPool);
    submitTasks(atomicInteger,threadPool);
    threadPool.shutdown();
    threadPool.awaitTermination(1, TimeUnit.HOURS);
}

實現這個功能主要依靠兩個地方的改進：

  • 我們需要重寫佇列的offer方法，直接返回false，這樣就會讓執行緒池有佇列已經滿的錯覺，offer方法的定義如下：
  • 在初始化執行緒池的時候提供一個我們自定義的拒絕處理程式，這個時候（最大執行緒達到的情況）再去把任務真正插入到佇列中去，RejectedExecutionHandler定義如下：

我們來看一下輸出：

10:53:37.889 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:37.898 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 0
10:53:37.901 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 0
10:53:37.901 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:37.901 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:37.901 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:38.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:38.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 0
10:53:38.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 0
10:53:38.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:38.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:38.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:38.919 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 1 started
10:53:39.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:39.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 1
10:53:39.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 1
10:53:39.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:39.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:39.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:39.924 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 2 started
10:53:40.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:40.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 2
10:53:40.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 2
10:53:40.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:40.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:40.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:40.930 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 3 started
10:53:41.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:41.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 3
10:53:41.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 3
10:53:41.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:41.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:41.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:41.934 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 4 started
10:53:42.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:42.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 4
10:53:42.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 4
10:53:42.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:42.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:42.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:42.935 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 5 started
10:53:43.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:43.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:43.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:43.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:43.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:53:43.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:44.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:44.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:44.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:44.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:44.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 1
10:53:44.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:45.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:45.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:45.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:45.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:45.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 2
10:53:45.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:46.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:46.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:46.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:46.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:46.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 3
10:53:46.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:47.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:47.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:47.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:47.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:47.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 4
10:53:47.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:48.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:48.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:48.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:48.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 0
10:53:48.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:53:48.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:48.921 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 1 finished
10:53:48.922 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 6 started
10:53:49.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:49.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:49.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:49.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 1
10:53:49.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:53:49.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:49.927 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 2 finished
10:53:49.928 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 7 started
10:53:50.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:50.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:50.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:50.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 2
10:53:50.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:53:50.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:50.933 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 3 finished
10:53:50.933 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 8 started
10:53:51.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:51.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:51.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:51.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 3
10:53:51.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:53:51.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:51.935 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 4 finished
10:53:51.935 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 9 started
10:53:52.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:52.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:52.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:52.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 4
10:53:52.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:53:52.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:52.937 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 5 finished
10:53:52.938 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 10 started
10:53:53.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:53.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:53.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:53.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 5
10:53:53.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:53:53.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:54.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:54.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:54.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:54.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 5
10:53:54.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 6
10:53:54.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:55.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:55.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:55.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:55.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 5
10:53:55.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 7
10:53:55.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:56.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:56.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:56.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:56.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 5
10:53:56.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 8
10:53:56.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:57.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:57.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:57.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:57.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 5
10:53:57.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 9
10:53:57.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:58.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:58.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:58.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:58.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 5
10:53:58.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 10
10:53:58.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:58.923 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 6 finished
10:53:58.923 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 11 started
10:53:59.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:59.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:53:59.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:53:59.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 6
10:53:59.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 9
10:53:59.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:53:59.931 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 7 finished
10:53:59.931 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 12 started
10:54:00.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:00.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:00.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:00.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 7
10:54:00.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 8
10:54:00.883 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:00.937 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 8 finished
10:54:00.938 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 13 started
10:54:01.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:01.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:01.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:01.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 8
10:54:01.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 7
10:54:01.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:01.937 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 9 finished
10:54:01.937 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 14 started
10:54:02.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:02.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:02.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:02.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 9
10:54:02.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 6
10:54:02.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:02.941 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 10 finished
10:54:02.941 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 15 started
10:54:03.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:03.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:03.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:03.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 10
10:54:03.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:54:03.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:04.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:04.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:04.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:04.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 10
10:54:04.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:54:04.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:05.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:05.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:05.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:05.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 10
10:54:05.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:54:05.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:06.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:06.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:06.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:06.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 10
10:54:06.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:54:06.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:07.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:07.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:07.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:07.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 10
10:54:07.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:54:07.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:08.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:08.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:08.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:08.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 10
10:54:08.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 5
10:54:08.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:08.927 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 11 finished
10:54:08.928 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 16 started
10:54:09.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:09.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:09.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:09.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 11
10:54:09.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 4
10:54:09.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:09.933 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 12 finished
10:54:09.933 [elastic-pool2] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 17 started
10:54:10.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:10.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:10.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:10.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 12
10:54:10.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 3
10:54:10.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:10.942 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 13 finished
10:54:10.942 [elastic-pool3] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 18 started
10:54:11.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:11.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:11.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:11.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 13
10:54:11.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 2
10:54:11.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:11.939 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 14 finished
10:54:11.939 [elastic-pool4] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 19 started
10:54:12.881 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:12.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:12.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:12.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 14
10:54:12.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 1
10:54:12.882 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:12.946 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 15 finished
10:54:12.946 [elastic-pool5] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 20 started
10:54:13.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:13.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:13.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:13.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 15
10:54:13.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:54:13.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:14.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:14.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:14.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:14.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 15
10:54:14.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:54:14.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:15.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:15.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:15.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:15.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 15
10:54:15.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:54:15.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:16.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:16.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:16.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:16.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 15
10:54:16.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:54:16.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:17.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:17.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:17.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:17.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 15
10:54:17.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:54:17.879 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:18.877 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:18.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Pool Size: 5
10:54:18.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Active Threads: 5
10:54:18.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks Completed: 15
10:54:18.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - Number of Tasks in Queue: 0
10:54:18.878 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:18.929 [elastic-pool1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - 16 finished
10:54:19.880 [pool-1-thread-1] INFO me.josephzhu.javaconcurrenttest.concurrent.executors.ThreadPoolExecutorTest - =========================
10:54:19.880 [pool-1-thread-

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