LockSupport

1. 简介

为构建锁和同步器提供基本的线程阻塞唤醒原语，LockSupport中的park()和unpark()的作用分别是阻塞线程和解除阻塞线程。类似于wait和notify，类似于await和signal。
2. 使用示例

// 1. pack unpack
public static void main(String[] args)
{
    Thread t1 = new Thread(() -> {
        try { 
            TimeUnit.SECONDS.sleep(3); 
        } catch (InterruptedException e) { 
            e.printStackTrace(); 
        }
        System.out.println(Thread.currentThread().getName() + "\t ----come in"+System.currentTimeMillis());
        LockSupport.park();
        System.out.println(Thread.currentThread().getName() + "\t ----被唤醒"+System.currentTimeMillis());}, "t1");
        t1.start();
        //暂停几秒钟线程
        //try { TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e) { e.printStackTrace(); }

        new Thread(() -> {
            LockSupport.unpark(t1);
            System.out.println(Thread.currentThread().getName()+"\t ----发出通知");
        },"t2").start();
}
// 2. await signal
private static void lockAwaitSignal()
{
    Lock lock = new ReentrantLock();
    Condition condition = lock.newCondition();
    new Thread(() -> {
        try { 
          TimeUnit.SECONDS.sleep(1); 
        } catch (InterruptedException e) { 
          e.printStackTrace(); 
        }
        lock.lock();
        try
        {
            System.out.println(Thread.currentThread().getName()+"\t ----come in");
            condition.await();
            System.out.println(Thread.currentThread().getName()+"\t ----被唤醒");
        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            lock.unlock();
        }},"t1").start();

        //暂停几秒钟线程
        //try { TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e) { e.printStackTrace(); }

    new Thread(() -> {
        lock.lock();
        try
        {
            condition.signal();
            System.out.println(Thread.currentThread().getName()+"\t ----发出通知");
        }finally {
            lock.unlock();
        }},"t2").start();
}

// 3. wait notify
private static void syncWaitNotify()
{
    Object objectLock = new Object();
    new Thread(() -> {
        try { 
          TimeUnit.SECONDS.sleep(1); 
        } catch (InterruptedException e) { 
          e.printStackTrace(); 
        }
        synchronized (objectLock){
            System.out.println(Thread.currentThread().getName()+"\t ----come in");
            try {
                objectLock.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println(Thread.currentThread().getName()+"\t ----被唤醒");
        }},"t1").start();

    //暂停几秒钟线程
    //try { TimeUnit.SECONDS.sleep(1); } catch (InterruptedException e) { e.printStackTrace(); }
    new Thread(() -> {
        synchronized (objectLock){
            objectLock.notify();
            System.out.println(Thread.currentThread().getName()+"\t ----发出通知");
        }},"t2").start();
}
LockSupport

1. 简介

2. 使用示例

3. 源码解析
