wait

I can't use shutdown() and awaitTermination() because it is possible new tasks will be added to the ThreadPoolExecutor while it is waiting. So I'm looking for a way to wait until the ThreadPoolExecutor has emptied it's queue and finished all of it's tasks without stopping new tasks from being added before that point. If it makes any difference, this is for Android. Thanks Update : Many weeks later after revisiting this, I discovered that a modified CountDownLatch worked better for me in this case. I'll keep the answer marked because it applies more to what I asked. If you are interested in

In a test spec, I need to click a button on a web page, and wait for the new page completely loaded. emailEl.sendKeys('jack'); passwordEl.sendKeys('123pwd'); btnLoginEl.click(); // ...Here need to wait for page complete... How? ptor.waitForAngular(); expect(ptor.getCurrentUrl()).toEqual(url + 'abc#/efg'); Depending on what you want to do, you can try: browser.waitForAngular(); or btnLoginEl.click().then(function() { // do some stuff }); to solve the promise. It would be better if you can do that in the beforeEach . NB: I noticed that the expect() waits for the promise inside (i.e.

多线程 1. 为什么需要同步与互斥 都需要访问/使用同一种资源； 多个任务之间有依赖关系，某个任务的运行依赖于另一个任务。 2. 同步 按照预定的先后顺序运行，比如A 任务的运行依赖于 B 任务产生的数据。 3. 互斥 一个公共资源同一时刻只能被一个进程或者线程使用，当某个任务运行其中一个程序片段时，其它任务就不能运行它们之中的任一程序片段当某个人物运行其中的 4. 互斥锁 #include <mutex> 互斥锁是一种简单的加锁的方法来控制对共享资源的访问，互斥锁只有两种状态,即上锁( lock )和解锁( unlock )。 特点：原子性，唯一性，非繁忙等待 非繁忙等待：如果一个线程已经锁定了一个互斥量，第二个线程又试图去锁定这个互斥量，则第二个线程将被挂起（不占用任何cpu资源），直到第一个线程解除对这个互斥量的锁定为止，第二个线程则被唤醒并继续执行，同时锁定这个互斥量。 5. 条件变量（同步） #include <condition_variable> 常用接口： notify_one()就是唤醒处于wait中的其中一个（随机）条件变量（可能当时有很多条件变量都处于wait状态）。 notify_all()（唤醒所有等待的线程） wait()可以让线程陷入休眠状态。 在wait()函数之前，使用互斥锁保护了，如果wait的时候什么都没做，岂不是一直持有互斥锁

If I just use synchronized, not wait/notify method, will it still keep thread-safe ? What's the difference ? Thx in advance. Using synchronized makes a method / block accessible by only on thread at a time. So, yes, it's thread-safe. The two concepts are combined, not mutually-exclusive. When you use wait() you need to own the monitor on that object. So you need to have synchronized(..) on it before that. Using .wait() makes the current thread stop until another thread calls .notify() on the object it waits on. This is an addition to synchronized , which just ensures that only one thread will

In java selenium-webdriver package, there is a FluentWait class: Each FluentWait instance defines the maximum amount of time to wait for a condition, as well as the frequency with which to check the condition. Furthermore, the user may configure the wait to ignore specific types of exceptions whilst waiting, such as NoSuchElementExceptions when searching for an element on the page. In other words, it is something more than implicit and explicit wait , gives you more control for waiting for an element. It can be very handy and definitely has use cases. Is there anything similar in python