public abstract class AbstractQueuedSynchronizer extends AbstractOwnableSynchronizer implements java.io.Serializable {
}

// 共享变量，使用volatile修饰保证线程可见性
private volatile int state;

//返回同步状态的当前值
protected final int getState() {
     return state;
}
 // 设置同步状态的值
protected final void setState(int newState) {
     state = newState;
}
//原子地（CAS操作）将同步状态值设置为给定值update如果当前同步状态的值等于expect（期望值）
protected final boolean compareAndSetState(int expect, int update) {
      return unsafe.compareAndSwapInt(this, stateOffset, expect, update);
}

//独占方式。尝试获取资源，成功则返回true，失败则返回false。
protected boolean tryAcquire(int)
//独占方式。尝试释放资源，成功则返回true，失败则返回false。
protected boolean tryRelease(int)
//共享方式。尝试获取资源。负数表示失败；0表示成功，但没有剩余可用资源；正数表示成功，且有剩余资源。
protected int tryAcquireShared(int)
//共享方式。尝试释放资源，成功则返回true，失败则返回false。
protected boolean tryReleaseShared(int)
//该线程是否正在独占资源。只有用到condition才需要去实现它。
protected boolean isHeldExclusively()

// AQS
public final void acquire(int arg) {
    if (!tryAcquire(arg) &&
        acquireQueued(addWaiter(Node.EXCLUSIVE), arg))
        selfInterrupt();
}

// AQS
protected boolean tryAcquire(int arg) {
    throw new UnsupportedOperationException();
}

// ReentrantLock
final boolean nonfairTryAcquire(int acquires) {
    final Thread current = Thread.currentThread();
    // 1、获取 AQS 中的 state 状态
    int c = getState();
    // 2、如果 state 为 0，证明锁没有被其他线程占用
    if (c == 0) {
        // 2.1、通过 CAS 对 state 进行更新
        if (compareAndSetState(0, acquires)) {
            // 2.2、如果 CAS 更新成功，就将锁的持有者设置为当前线程
            setExclusiveOwnerThread(current);
            return true;
        }
    }
    // 3、如果当前线程和锁的持有线程相同，说明发生了「锁的重入」
    else if (current == getExclusiveOwnerThread()) {
        int nextc = c + acquires;
        if (nextc < 0) // overflow
            throw new Error("Maximum lock count exceeded");
        // 3.1、将锁的重入次数加 1
        setState(nextc);
        return true;
    }
    // 4、如果锁被其他线程占用，就返回 false，表示获取锁失败
    return false;
}

// AQS
private Node addWaiter(Node mode) {
    // 1、将当前线程封装为 Node 节点。
    Node node = new Node(Thread.currentThread(), mode);
    Node pred = tail;
    // 2、如果 pred ！= null，则证明 tail 节点已经被初始化，直接将 Node 节点加入队列即可。
    if (pred != null) {
        node.prev = pred;
        // 2.1、通过 CAS 控制并发安全。
        if (compareAndSetTail(pred, node)) {
            pred.next = node;
            return node;
        }
    }
    // 3、初始化队列，并将新创建的 Node 节点加入队列。
    enq(node);
    return node;
}

// AQS
private Node enq(final Node node) {
    for (;;) {
        Node t = tail;
        if (t == null) {
            // 1、通过 CAS 操作保证队列初始化的并发安全
            if (compareAndSetHead(new Node()))
                tail = head;
        } else {
            // 2、与 addWaiter() 方法中节点入队的操作相同
            node.prev = t;
            if (compareAndSetTail(t, node)) {
                t.next = node;
                return t;
            }
        }
    }
}

// AQS
public final void acquire(int arg) {
    if (!tryAcquire(arg) &&
        acquireQueued(addWaiter(Node.EXCLUSIVE), arg))
        selfInterrupt();
}

// AQS：令队列中的节点尝试获取锁，并且对线程进行阻塞。
final boolean acquireQueued(final Node node, int arg) {
    boolean failed = true;
    try {
        boolean interrupted = false;
        for (;;) {
            // 1、尝试获取锁。
            final Node p = node.predecessor();
            if (p == head && tryAcquire(arg)) {
                setHead(node);
                p.next = null; // help GC
                failed = false;
                return interrupted;
            }
            // 2、判断线程是否可以阻塞，如果可以，则阻塞当前线程。
            if (shouldParkAfterFailedAcquire(p, node) &&
                parkAndCheckInterrupt())
                interrupted = true;
        }
    } finally {
        // 3、如果获取锁失败，就会取消获取锁，将节点状态更新为 CANCELLED。
        if (failed)
            cancelAcquire(node);
    }
}

// AQS：判断当前线程节点是否可以阻塞。
private static boolean shouldParkAfterFailedAcquire(Node pred, Node node) {
    int ws = pred.waitStatus;
    // 1、前继节点状态正常，直接返回 true 即可。
    if (ws == Node.SIGNAL)
        return true;
    // 2、ws > 0 表示前继节点的状态异常，即为 CANCELLED 状态，需要跳过异常状态的节点。
    if (ws > 0) {
        do {
            node.prev = pred = pred.prev;
        } while (pred.waitStatus > 0);
        pred.next = node;
    } else {
        // 3、如果前继节点的状态不是 SIGNAL，也不是 CANCELLED，就将状态设置为 SIGNAL。
        compareAndSetWaitStatus(pred, ws, Node.SIGNAL);
    }
    return false;
}

// AQS
private final boolean parkAndCheckInterrupt() {
    // 1、线程阻塞到这里
    LockSupport.park(this);
    // 2、线程被唤醒之后，返回线程中断状态
    return Thread.interrupted();
}

// AQS
private final boolean parkAndCheckInterrupt() {
    LockSupport.park(this);
    // 线程被唤醒之后，需要返回线程中断状态
    return Thread.interrupted();
}

// AQS
public final void acquire(int arg) {
    if (!tryAcquire(arg) &&
        acquireQueued(addWaiter(Node.EXCLUSIVE), arg))
        selfInterrupt();
}

// AQS
public final boolean release(int arg) {
    // 1、尝试释放锁
    if (tryRelease(arg)) {
        Node h = head;
        // 2、唤醒后继节点
        if (h != null && h.waitStatus != 0)
            unparkSuccessor(h);
        return true;
    }
    return false;
}

// ReentrantLock
protected final boolean tryRelease(int releases) {
    int c = getState() - releases;
    // 1、判断持有锁的线程是否为当前线程
    if (Thread.currentThread() != getExclusiveOwnerThread())
        throw new IllegalMonitorStateException();
    boolean free = false;
    // 2、如果 state 为 0，则表明当前线程已经没有重入次数。因此将 free 更新为 true，表明该线程会释放锁。
    if (c == 0) {
        free = true;
        // 3、更新持有资源的线程为 null
        setExclusiveOwnerThread(null);
    }
    // 4、更新 state 值
    setState(c);
    return free;
}

// AQS：这里的入参 node 为队列的头节点（虚拟头节点）
private void unparkSuccessor(Node node) {
    int ws = node.waitStatus;
    // 1、将头节点的状态进行清除，为后续的唤醒做准备。
    if (ws < 0)
        compareAndSetWaitStatus(node, ws, 0);

    Node s = node.next;
    // 2、如果后继节点异常，则需要从 tail 向前遍历，找到正常状态的节点进行唤醒。
    if (s == null || s.waitStatus > 0) {
        s = null;
        for (Node t = tail; t != null && t != node; t = t.prev)
            if (t.waitStatus <= 0)
                s = t;
    }
    if (s != null)
        // 3、唤醒后继节点
        LockSupport.unpark(s.thread);
}

// AQS：节点入队方法
private Node addWaiter(Node mode) {
    Node node = new Node(Thread.currentThread(), mode);
    Node pred = tail;
    if (pred != null) {
        // 1、先修改 prev 指针。
        node.prev = pred;
        if (compareAndSetTail(pred, node)) {
            // 2、再修改 next 指针。
            pred.next = node;
            return node;
        }
    }
    enq(node);
    return node;
}

// AQS
public final void acquireShared(int arg) {
    if (tryAcquireShared(arg) < 0)
        doAcquireShared(arg);
}

// Semaphore 重写 AQS 的模板方法
protected int tryAcquireShared(int acquires) {
    return nonfairTryAcquireShared(acquires);
}

// Semaphore
final int nonfairTryAcquireShared(int acquires) {
    for (;;) {
        // 1、获取可用资源数量。
        int available = getState();
        // 2、计算剩余资源数量。
        int remaining = available - acquires;
        // 3、如果剩余资源数量 < 0，则说明资源不足，直接返回；如果 CAS 更新 state 成功，则说明当前线程获取到了共享资源，直接返回。
        if (remaining < 0 ||
            compareAndSetState(available, remaining))
            return remaining;
    }
}

// AQS
public final void acquireShared(int arg) {
    if (tryAcquireShared(arg) < 0)
        doAcquireShared(arg);
}

// AQS
private void doAcquireShared(int arg) {
    // 1、将当前线程加入到队列中等待。
    final Node node = addWaiter(Node.SHARED);
    boolean failed = true;
    try {
        boolean interrupted = false;
        for (;;) {
            final Node p = node.predecessor();
            if (p == head) {
                // 2、如果当前线程是等待队列的第一个节点，则尝试获取资源。
                int r = tryAcquireShared(arg);
                if (r >= 0) {
					// 3、将当前线程节点移出等待队列，并唤醒后续线程节点。
                    setHeadAndPropagate(node, r);
                    p.next = null; // help GC
                    if (interrupted)
                        selfInterrupt();
                    failed = false;
                    return;
                }
            }
            if (shouldParkAfterFailedAcquire(p, node) &&
                parkAndCheckInterrupt())
                interrupted = true;
        }
    } finally {
        // 3、如果获取资源失败，就会取消获取资源，将节点状态更新为 CANCELLED。
        if (failed)
            cancelAcquire(node);
    }
}

// AQS
private void setHeadAndPropagate(Node node, int propagate) {
    Node h = head;
    // 1、将当前线程节点移出等待队列。
    setHead(node);
	// 2、唤醒后续等待节点。
    if (propagate > 0 || h == null || h.waitStatus < 0 ||
        (h = head) == null || h.waitStatus < 0) {
        Node s = node.next;
        if (s == null || s.isShared())
            doReleaseShared();
    }
}

if (propagate > 0 || h == null || h.waitStatus < 0 ||
    (h = head) == null || h.waitStatus < 0)

private void doReleaseShared() {
    for (;;) {
        Node h = head;
        // 1、队列中至少需要一个等待的线程节点。
        if (h != null && h != tail) {
            int ws = h.waitStatus;
            // 2、如果 head 节点的状态为 SIGNAL，则可以唤醒后继节点。
            if (ws == Node.SIGNAL) {
                // 2.1 清除 head 节点的 SIGNAL 状态，更新为 0。表示已经唤醒该节点的后继节点了。
                if (!compareAndSetWaitStatus(h, Node.SIGNAL, 0))
                    continue;
                // 2.2 唤醒后继节点
                unparkSuccessor(h);
            }
            // 3、如果 head 节点的状态为 0，则更新为 PROPAGATE。这是为了解决并发场景下存在的问题，接下来会细讲。
            else if (ws == 0 &&
                     !compareAndSetWaitStatus(h, 0, Node.PROPAGATE))
                continue;
        }
        if (h == head)
            break;
    }
}

// AQS
public final boolean releaseShared(int arg) {
    if (tryReleaseShared(arg)) {
        doReleaseShared();
        return true;
    }
    return false;
}

// Semaphore
protected final boolean tryReleaseShared(int releases) {
    for (;;) {
        int current = getState();
        int next = current + releases;
        if (next < current) // overflow
            throw new Error("Maximum permit count exceeded");
        if (compareAndSetState(current, next))
            return true;
    }
}

// 初始共享资源数量
final Semaphore semaphore = new Semaphore(5);
// 获取1个许可
semaphore.acquire();
// 释放1个许可
semaphore.release();

public Semaphore(int permits) {
    sync = new NonfairSync(permits);
}

public Semaphore(int permits, boolean fair) {
    sync = fair ? new FairSync(permits) : new NonfairSync(permits);
}

// 获取1个许可证
public void acquire() throws InterruptedException {
    sync.acquireSharedInterruptibly(1);
}

// 获取一个或者多个许可证
public void acquire(int permits) throws InterruptedException {
    if (permits < 0) throw new IllegalArgumentException();
    sync.acquireSharedInterruptibly(permits);
}

// 共享模式下获取许可证，获取成功则返回，失败则加入等待队列，挂起线程
public final void acquireSharedInterruptibly(int arg)
    throws InterruptedException {
    if (Thread.interrupted())
      throw new InterruptedException();
        // 尝试获取许可证，arg为获取许可证个数，当获取失败时,则创建一个节点加入等待队列，挂起当前线程。
    if (tryAcquireShared(arg) < 0)
      doAcquireSharedInterruptibly(arg);
}

// 共享模式下尝试获取资源(在Semaphore中的资源即许可证):
protected int tryAcquireShared(int acquires) {
    return nonfairTryAcquireShared(acquires);
}

// 非公平的共享模式获取许可证
final int nonfairTryAcquireShared(int acquires) {
    for (;;) {
        // 当前可用许可证数量
        int available = getState();
        /*
         * 尝试获取许可证，当前可用许可证数量小于等于0时，返回负值，表示获取失败，
         * 当前可用许可证大于0时才可能获取成功，CAS失败了会循环重新获取最新的值尝试获取
         */
        int remaining = available - acquires;
        if (remaining < 0 ||
            compareAndSetState(available, remaining))
            return remaining;
    }
}

// 释放一个许可证
public void release() {
    sync.releaseShared(1);
}

// 释放一个或者多个许可证
public void release(int permits) {
    if (permits < 0) throw new IllegalArgumentException();
    sync.releaseShared(permits);
}

// 释放共享锁
// 如果 tryReleaseShared 返回 true，就唤醒等待队列中的一个或多个线程。
public final boolean releaseShared(int arg) {
    //释放共享锁
    if (tryReleaseShared(arg)) {
      //释放当前节点的后置等待节点
      doReleaseShared();
      return true;
    }
    return false;
}

// 内部类 Sync 中重写的一个方法
// 尝试释放资源
protected final boolean tryReleaseShared(int releases) {
    for (;;) {
        int current = getState();
        // 可用许可证+1
        int next = current + releases;
        if (next < current) // overflow
            throw new Error("Maximum permit count exceeded");
         // CAS修改state的值
        if (compareAndSetState(current, next))
            return true;
    }
}

private static final class Sync extends AbstractQueuedSynchronizer {
  // ...
}
static final class NonfairSync extends Sync {
  // ...
}
static final class FairSync extends Sync {
  // ...
}

public class SemaphoreExample {
  // 请求的数量
  private static final int threadCount = 550;

  public static void main(String[] args) throws InterruptedException {
    // 创建一个具有固定线程数量的线程池对象（如果这里线程池的线程数量给太少的话你会发现执行的很慢）
    ExecutorService threadPool = Executors.newFixedThreadPool(300);
    // 初始许可证数量
    final Semaphore semaphore = new Semaphore(20);

    for (int i = 0; i < threadCount; i++) {
      final int threadnum = i;
      threadPool.execute(() -> {// Lambda 表达式的运用
        try {
          semaphore.acquire();// 获取一个许可，所以可运行线程数量为20/1=20
          test(threadnum);
          semaphore.release();// 释放一个许可
        } catch (InterruptedException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }

      });
    }
    threadPool.shutdown();
    System.out.println("finish");
  }

  public static void test(int threadnum) throws InterruptedException {
    Thread.sleep(1000);// 模拟请求的耗时操作
    System.out.println("threadnum:" + threadnum);
    Thread.sleep(1000);// 模拟请求的耗时操作
  }
}

semaphore.acquire(5);// 获取5个许可，所以可运行线程数量为20/5=4
test(threadnum);
semaphore.release(5);// 释放5个许可

public CountDownLatch(int count) {
    if (count < 0) throw new IllegalArgumentException("count < 0");
    this.sync = new Sync(count);
}

private static final class Sync extends AbstractQueuedSynchronizer {
    Sync(int count) {
        setState(count);
    }
  //...
}

public void countDown() {
    // Sync 是 CountDownLatch 的内部类 , 继承了 AbstractQueuedSynchronizer
    sync.releaseShared(1);
}

// 释放共享锁
// 如果 tryReleaseShared 返回 true，就唤醒等待队列中的一个或多个线程。
public final boolean releaseShared(int arg) {
    //释放共享锁
    if (tryReleaseShared(arg)) {
      //释放当前节点的后置等待节点
      doReleaseShared();
      return true;
    }
    return false;
}

// 对 state 进行递减，直到 state 变成 0；
// 只有 count 递减到 0 时，countDown 才会返回 true
protected boolean tryReleaseShared(int releases) {
    // 自选检查 state 是否为 0
    for (;;) {
        int c = getState();
        // 如果 state 已经是 0 了，直接返回 false
        if (c == 0)
            return false;
        // 对 state 进行递减
        int nextc = c-1;
        // CAS 操作更新 state 的值
        if (compareAndSetState(c, nextc))
            return nextc == 0;
    }
}

// 等待（也可以叫做加锁）
public void await() throws InterruptedException {
    sync.acquireSharedInterruptibly(1);
}
// 带有超时时间的等待
public boolean await(long timeout, TimeUnit unit)
    throws InterruptedException {
    return sync.tryAcquireSharedNanos(1, unit.toNanos(timeout));
}

// 尝试获取锁，获取成功则返回，失败则加入等待队列，挂起线程
public final void acquireSharedInterruptibly(int arg)
    throws InterruptedException {
    if (Thread.interrupted())
      throw new InterruptedException();
        // 尝试获得锁，获取成功则返回
    if (tryAcquireShared(arg) < 0)
      // 获取失败加入等待队列，挂起线程
      doAcquireSharedInterruptibly(arg);
}

protected int tryAcquireShared(int acquires) {
    return (getState() == 0) ? 1 : -1;
}

public class CountDownLatchExample {
  // 请求的数量
  private static final int THREAD_COUNT = 550;

  public static void main(String[] args) throws InterruptedException {
    // 创建一个具有固定线程数量的线程池对象（如果这里线程池的线程数量给太少的话你会发现执行的很慢）
    // 只是测试使用，实际场景请手动赋值线程池参数
    ExecutorService threadPool = Executors.newFixedThreadPool(300);
    final CountDownLatch countDownLatch = new CountDownLatch(THREAD_COUNT);
    for (int i = 0; i < THREAD_COUNT; i++) {
      final int threadNum = i;
      threadPool.execute(() -> {
        try {
          test(threadNum);
        } catch (InterruptedException e) {
          e.printStackTrace();
        } finally {
          // 表示一个请求已经被完成
          countDownLatch.countDown();
        }

      });
    }
    countDownLatch.await();
    threadPool.shutdown();
    System.out.println("finish");
  }

  public static void test(int threadnum) throws InterruptedException {
    Thread.sleep(1000);
    System.out.println("threadNum:" + threadnum);
    Thread.sleep(1000);
  }
}

for (int i = 0; i < threadCount-1; i++) {
.......
}

//每次拦截的线程数
private final int parties;
//计数器
private int count;

public CyclicBarrier(int parties) {
    this(parties, null);
}

public CyclicBarrier(int parties, Runnable barrierAction) {
    if (parties <= 0) throw new IllegalArgumentException();
    this.parties = parties;
    this.count = parties;
    this.barrierCommand = barrierAction;
}

public int await() throws InterruptedException, BrokenBarrierException {
  try {
      return dowait(false, 0L);
  } catch (TimeoutException toe) {
      throw new Error(toe); // cannot happen
  }
}

    // 当线程数量或者请求数量达到 count 时 await 之后的方法才会被执行。上面的示例中 count 的值就为 5。
    private int count;
    /**
     * Main barrier code, covering the various policies.
     */
    private int dowait(boolean timed, long nanos)
        throws InterruptedException, BrokenBarrierException,
               TimeoutException {
        final ReentrantLock lock = this.lock;
        // 锁住
        lock.lock();
        try {
            final Generation g = generation;

            if (g.broken)
                throw new BrokenBarrierException();

            // 如果线程中断了，抛出异常
            if (Thread.interrupted()) {
                breakBarrier();
                throw new InterruptedException();
            }
            // count 减1
            int index = --count;
            // 当 count 数量减为 0 之后说明最后一个线程已经到达栅栏了，也就是达到了可以执行await 方法之后的条件
            if (index == 0) {  // tripped
                boolean ranAction = false;
                try {
                    final Runnable command = barrierCommand;
                    if (command != null)
                        command.run();
                    ranAction = true;
                    // 将 count 重置为 parties 属性的初始化值
                    // 唤醒之前等待的线程
                    // 下一波执行开始
                    nextGeneration();
                    return 0;
                } finally {
                    if (!ranAction)
                        breakBarrier();
                }
            }

            // loop until tripped, broken, interrupted, or timed out
            for (;;) {
                try {
                    if (!timed)
                        trip.await();
                    else if (nanos > 0L)
                        nanos = trip.awaitNanos(nanos);
                } catch (InterruptedException ie) {
                    if (g == generation && ! g.broken) {
                        breakBarrier();
                        throw ie;
                    } else {
                        // We're about to finish waiting even if we had not
                        // been interrupted, so this interrupt is deemed to
                        // "belong" to subsequent execution.
                        Thread.currentThread().interrupt();
                    }
                }

                if (g.broken)
                    throw new BrokenBarrierException();

                if (g != generation)
                    return index;

                if (timed && nanos <= 0L) {
                    breakBarrier();
                    throw new TimeoutException();
                }
            }
        } finally {
            lock.unlock();
        }
    }

public class CyclicBarrierExample1 {
  // 请求的数量
  private static final int threadCount = 550;
  // 需要同步的线程数量
  private static final CyclicBarrier cyclicBarrier = new CyclicBarrier(5);

  public static void main(String[] args) throws InterruptedException {
    // 创建线程池
    ExecutorService threadPool = Executors.newFixedThreadPool(10);

    for (int i = 0; i < threadCount; i++) {
      final int threadNum = i;
      Thread.sleep(1000);
      threadPool.execute(() -> {
        try {
          test(threadNum);
        } catch (InterruptedException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        } catch (BrokenBarrierException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
      });
    }
    threadPool.shutdown();
  }

  public static void test(int threadnum) throws InterruptedException, BrokenBarrierException {
    System.out.println("threadnum:" + threadnum + "is ready");
    try {
      /**等待60秒，保证子线程完全执行结束*/
      cyclicBarrier.await(60, TimeUnit.SECONDS);
    } catch (Exception e) {
      System.out.println("-----CyclicBarrierException------");
    }
    System.out.println("threadnum:" + threadnum + "is finish");
  }

}

threadnum:0is ready
threadnum:1is ready
threadnum:2is ready
threadnum:3is ready
threadnum:4is ready
threadnum:4is finish
threadnum:0is finish
threadnum:1is finish
threadnum:2is finish
threadnum:3is finish
threadnum:5is ready
threadnum:6is ready
threadnum:7is ready
threadnum:8is ready
threadnum:9is ready
threadnum:9is finish
threadnum:5is finish
threadnum:8is finish
threadnum:7is finish
threadnum:6is finish
......

public class CyclicBarrierExample2 {
  // 请求的数量
  private static final int threadCount = 550;
  // 需要同步的线程数量
  private static final CyclicBarrier cyclicBarrier = new CyclicBarrier(5, () -> {
    System.out.println("------当线程数达到之后，优先执行------");
  });

  public static void main(String[] args) throws InterruptedException {
    // 创建线程池
    ExecutorService threadPool = Executors.newFixedThreadPool(10);

    for (int i = 0; i < threadCount; i++) {
      final int threadNum = i;
      Thread.sleep(1000);
      threadPool.execute(() -> {
        try {
          test(threadNum);
        } catch (InterruptedException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        } catch (BrokenBarrierException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
      });
    }
    threadPool.shutdown();
  }

  public static void test(int threadnum) throws InterruptedException, BrokenBarrierException {
    System.out.println("threadnum:" + threadnum + "is ready");
    cyclicBarrier.await();
    System.out.println("threadnum:" + threadnum + "is finish");
  }

}

threadnum:0is ready
threadnum:1is ready
threadnum:2is ready
threadnum:3is ready
threadnum:4is ready
------当线程数达到之后，优先执行------
threadnum:4is finish
threadnum:0is finish
threadnum:2is finish
threadnum:1is finish
threadnum:3is finish
threadnum:5is ready
threadnum:6is ready
threadnum:7is ready
threadnum:8is ready
threadnum:9is ready
------当线程数达到之后，优先执行------
threadnum:9is finish
threadnum:5is finish
threadnum:6is finish
threadnum:8is finish
threadnum:7is finish
......