精华内容
下载资源
问答
  • Thread is in the Blocked state while waiting for the monitor lock to enter a synchronized block or method or to reenter a synchronized block or method after calling Object.wait().这个地方是说...

    Thread is in the Blocked state while waiting for the monitor lock to enter a synchronized block or method or to reenter a synchronized block or method after calling Object.wait().

    这个地方是说synchronized会导致线程进入Blocked状态,Object.wait()导致线程进入Waiting状态,Waiting线程被其他线程调用Object.notify()唤醒之后,重新获取对象上的锁的时候也会进入Blocked状态

    * The current thread must own this object's monitor. The thread

    * releases ownership of this monitor and waits until another thread

    * notifies threads waiting on this object's monitor to wake up

    * either through a call to the {@codenotify} method or the

    * {@codenotifyAll} method. The thread then waits until it can

    * re-obtain ownership of the monitor and resumes execution.

    这是Object.wait()方法的注释,最后一句指明被唤醒的线程需要重新获取到对象的锁才能恢复执行

    * The awakened thread will not be able to proceed until the current

    * thread relinquishes the lock on this object. The awakened thread will

    * compete in the usual manner with any other threads that might be

    * actively competing to synchronize on this object; for example, the

    * awakened thread enjoys no reliable privilege or disadvantage in being

    * the next thread to lock this object.

    这是Object.notify()方法的注释,第一句也说被唤醒的线程需要获取对象的锁

    也就是说只有synchronized会导致线程进入Blocked状态,Waiting状态只能进入Blocked状态,获取锁之后才能恢复执行。

    展开全文
  • java 线程中sleep和wait有一个共同作用,停止当前线程任务运行,但他们存在一定不同,首先我们先看sleep中构造函数 [table] |sleep(long millis) Causes the currently executing thread to sleep ...
    java 线程中的sleep和wait有一个共同作用,停止当前线程任务运行,但他们存在一定的不同,首先我们先看sleep中的构造函数
    [table]
    |sleep(long millis)
    Causes the currently executing thread to sleep (temporarily cease execution) for the specified number of milliseconds, subject to the precision and accuracy of system timers and schedulers.
    |
    |
    |
    |sleep(long millis, int nanos)
    Causes the currently executing thread to sleep (cease execution) for the specified number of milliseconds plus the specified number of nanoseconds, subject to the precision and accuracy of system timers and schedulers.|
    [/table]
    sleep方法属于Thread类中方法,表示让一个线程进入睡眠状态,等待一定的时间之后,自动醒来进入到可运行状态,不会马上进入运行状态,因为线程调度机制恢复线程的运行也需要时间,一个线程对象调用了sleep方法之后,并不会释放他所持有的所有对象锁,所以也就不会影响其他进程对象的运行。但在sleep的过程中过程中有可能被其他对象调用它的interrupt(),产生InterruptedException异常,如果你的程序不捕获这个异常,线程就会异常终止,进入TERMINATED状态,如果你的程序捕获了这个异常,那么程序就会继续执行catch语句块(可能还有finally语句块)以及以后的代码。

    注意sleep()方法是一个静态方法,也就是说他只对当前对象有效,通过t.sleep()让t对象进入sleep,这样的做法是错误的,它只会是使当前线程被sleep 而不是t线程

    wait方法
    [table]
    |void wait(long timeout)
    |
    | Causes the current thread to wait until either another thread invokes the notify() method or the notifyAll() method for this object, or a specified amount of time has elapsed.
    |
    | void wait(long timeout, int nanos)
    |
    | Causes the current thread to wait until another thread invokes the notify() method or the notifyAll() method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed. |
    [/table]

    wait属于Object的成员方法,一旦一个对象调用了wait方法,必须要采用notify()和notifyAll()方法唤醒该进程;如果线程拥有某个或某些对象的同步锁,那么在调用了wait()后,这个线程就会释放它持有的所有同步资源,而不限于这个被调用了wait()方法的对象。wait()方法也同样会在wait的过程中有可能被其他对象调用interrupt()方法而产生
    InterruptedException,效果以及处理方式同sleep()方法
    展开全文
  • Yes, I know both are used to wait for some specified time.Selenium:driver.implicitly_wait(10)Python:import timetime.sleep(10)Is there any difference between these two?解决方案time.sleep(secs)time....

    Yes, I know both are used to wait for some specified time.

    Selenium:

    driver.implicitly_wait(10)

    Python:

    import time

    time.sleep(10)

    Is there any difference between these two?

    解决方案

    time.sleep(secs)

    time.sleep(secs) suspends the execution of the current thread for the given number of seconds. The argument may be a floating point number to indicate a more precise sleep time. The actual suspension time may be less than that requested because any caught signal will terminate the sleep() following execution of that signal’s catching routine. Also, the suspension time may be longer than requested by an arbitrary amount because of the scheduling of other activity in the system.

    implicitly_wait(time_to_wait)

    implicitly_wait(time_to_wait) is to specify the amount of time the WebDriver instance i.e. the driver should wait when searching for an element if it is not immediately present in the HTML DOM in-terms of SECONDS when trying to find an element or elements if they are not immediately available. The default setting is 0 which means the driver when finds an instruction to find an element or elements, the search starts and results are available on immediate basis.

    In this case, after a fresh loading of a webpage an element or elements may be / may not be found on an immediate search. So your Automation Script may be facing any of these exceptions:

    Hence we introduce ImplicitWait. By introducing ImplicitWait the driver will poll the DOM Tree until the element has been found for the configured amount of time looking out for the element or elements before throwing a NoSuchElementException. By that time the element or elements for which you had been looking for may be available in the HTML DOM. As in your code you have already set ImplicitWait to a value of 10 seconds, the driver will poll the HTML DOM for 10 seconds.

    You can find a detailed discussion in Using implicit wait in selenium

    展开全文
  • Thread is in the Blocked state while waiting for the monitor lock to enter a synchronized block or method or to reenter a synchronized block or method after calling Object.wait().这个地方是说...

    Thread is in the Blocked state while waiting for the monitor lock to enter a synchronized block or method or to reenter a synchronized block or method after calling Object.wait().

    这个地方是说synchronized会导致线程进入Blocked状态,Object.wait()导致线程进入Waiting状态,Waiting线程被其他线程调用Object.notify()唤醒之后,重新获取对象上的锁的时候也会进入Blocked状态

    * The current thread must own this object's monitor. The thread

    * releases ownership of this monitor and waits until another thread

    * notifies threads waiting on this object's monitor to wake up

    * either through a call to the {@codenotify} method or the

    * {@codenotifyAll} method. The thread then waits until it can

    * re-obtain ownership of the monitor and resumes execution.

    这是Object.wait()方法的注释,最后一句指明被唤醒的线程需要重新获取到对象的锁才能恢复执行

    * The awakened thread will not be able to proceed until the current

    * thread relinquishes the lock on this object. The awakened thread will

    * compete in the usual manner with any other threads that might be

    * actively competing to synchronize on this object; for example, the

    * awakened thread enjoys no reliable privilege or disadvantage in being

    * the next thread to lock this object.

    这是Object.notify()方法的注释,第一句也说被唤醒的线程需要获取对象的锁

    也就是说只有synchronized会导致线程进入Blocked状态,Waiting状态只能进入Blocked状态,获取锁之后才能恢复执行。

    展开全文
  • sleep和wait

    2017-10-22 15:47:59
    多线程问题中,经常问的一点就是sleep方法和wait方法的区别,如果没有看过源码,估计很多人死记硬背理解不了,还是老规矩,看源码理解。1 注释的源码Sleep Causes the currently executing thread to sleep ...
  • API给出解释是: Waits for this thread to die.但是好像joindie没有什么关系啊,为何要用join呢?  子线程join到主线程(启动程序线程,比如c语言执行main函数线程)。你问题可能在于没有理解jo...
  • log file parallel write log file sync这两个等待事件关系密切,很多人对这两个等待事件有一些误解,我们先来看看Oracle官方...Wait Time: Time it takes for the I/Os to complete. Even though redo records are
  • 三个区别: 1、接收参数不一样 ...Method submit extends base method Executor.execute by creating and returning a Future that can be used to cancel execution and/or wait for completion.
  • 看了有关这个问题几篇博文,几乎都是引用了stackoverflow上一个回答;问题: I know that a fragment’s view hierarchy has to be inflated in onCreateView, but what other ... what should wait for on
  • Python中OpenCVMatplotlib的区别

    千次阅读 2019-03-30 19:30:26
    1、opencv基本操作: import numpy as np import cv2 img = cv2.imread('messi5.jpg',0) cv2.imshow('image',img) ...if k == 27: # wait for ESC key to exit cv2.destroyAllWindows() elif k == ...
  • 看了有关这个问题几篇博文,几乎都是引用了stackoverflow上一个回答; 问题: I know that a fragment’s view hierarchy has to be inflated in onCreateView, but what other ... what should wait for ...
  • man tailf 结果如下: ... tailf will print out the last 10 lines of a file and then wait for the file to grow. It is similar to tail -f but does not access the file when it is not growing. This has th...
  • #### 最近在看关于epollselect相关问题,但是并没有发现javaselectlinuxepoll有什么区别 #### javanio select代码如下 ``` import java.io.IOException; import java.net.InetSocketAddress; ...
  • Promises to wait for each other’s completion: import { createStore, applyMiddleware } from 'redux'; import thunk from 'redux-thunk'; import rootReducer from './reducers'; // Note: this API requires ...
  • 三个区别:1、接收参数不一样2、submit有返回值,而execute没有Method submit extends base method Executor.execute by creating and returning a Future that can be used to cancel execution and/or wait for ...
  • 由Thread.sleep引发

    千次阅读 2013-11-14 16:29:14
    首先,对比下sleep和wait的区别 sleep() is a method which is used to hold the process for few seconds or the time you wanted but in case of wait() method thread goes in waiting state and it ...
  • C# 多线程与异步编程

    2020-10-05 15:12:59
    写在前面 自从介入UI界面编程以后,就免不了使用...Asynchronous programming is a bit more general in that it has to do with latency (something on which your application has to wait, for one reason or anothe
  • case EXOSIP_CALL_MESSAGE_NEW://至于该类型EXOSIP_MESSAGE_NEW的区别,源代码这么解释的 /* // request related events within calls (except INVITE) EXOSIP_CALL_MESSAGE_NEW, // response received for ...
  • 用户系统百分比之(us+sy)接近 100 时,说明 CPU 繁忙,但并不意味着 CPU 过载。sr 超过 CPU 数量时候意味着 CPU 过载。当 CPU 等待(wa)超过 20 时候,那么 20%或者更多处理 时间在等待资源,通常是 I/O。...
  • java中wait和sleep的区别 java中Future的使用 java并发中ExecutorService的使用 java中RunnableCallable的区别 java中ThreadLocal的使用 java中线程的生命周期 java中join的使用 怎么在java中关闭一个thread java...
  • <div><p>本文是对Node.js官方文档<a href="https://nodejs.org/en/docs/guides/event-loop-timers-and-nexttick/">The Node.js Event Loop, Timers, and <code>process.nextTick()</code></a>翻译理解。...
  • * Attach file descriptors 0, 1, and 2 to /dev/null. */ int fd0, fd1, fd2; fd0 = open("/dev/null", O_RDWR); fd1 = dup(0); fd2 = dup(0); if (fd0 != 0 || fd1 != 1 || fd2 != 2) { printf("init ...
  • How long (in seconds) will wait for a new command from the client before assuming the client quit and ending the uiautomator service (Default 3 minutes) 配置accessibility服务最大空闲时间,超时将...

空空如也

空空如也

1 2 3
收藏数 59
精华内容 23
关键字:

for的区别to和waitwait