什么是ReentrantLock＃tryLock（long，TimeUnit）在尝试获取锁时做什么？(What is ReentrantLock#tryLock(long,TimeUnit) doing when it tries to aquire the lock?)

 什么是ReentrantLock＃tryLock（long，TimeUnit）实现在尝试获取锁时执行的操作？ 假设线程A拥有myLock的锁，并且线程B调用myLock.tryLock(10,SECONDS) ，线程B是否正在睡眠或等待？ 
 
 换句话说，这两个实现的区别在于： 
 
 1。 
 
while (true)
   try {
     if (readLock.tryLock())
       return;
     MILLISECONDS.sleep(5);
   }catch (InterruptedException e) {}
 
 2。 
 
 while (true)
   try {
     if (readLock.tryLock(5,MILLISECONDS))
       return;
   }catch (InterruptedException e) {}

What is the ReentrantLock#tryLock(long,TimeUnit) implementation doing when it tries to aquire a lock ? Assume Thread A acually owns the Lock of myLock, and Thread B call myLock.tryLock(10,SECONDS), is Thread B sleeping or waiting ?
 
In other words, was is the difference of this 2 implementations:
 
1.
 
while (true)
   try {
     if (readLock.tryLock())
       return;
     MILLISECONDS.sleep(5);
   }catch (InterruptedException e) {}
 
2.
 
 while (true)
   try {
     if (readLock.tryLock(5,MILLISECONDS))
       return;
   }catch (InterruptedException e) {}

原文：https://stackoverflow.com/questions/8398371