wait

问题 all. I have a question for Java wait-notify mechanism. The answer is is there a guaranty that the threads will be executed in this order - from last to the first etc. the result always will be 100, 99, ... , 1 ? This is the snippet of code: public class Main { static int counter = 0; static Object o = new Object(); public static void main(String[] args){ for(int i = 0; i < 100; ++i){ new Thread(() -> { synchronized (o) { try { int c = ++counter; o.wait(); System.out.println("" + c); Thread

问题 I am using this code I found on the Internet and on some devices it waits, but on others it does not. Can someone please explain where I am going wrong. My app loads in Truecrypt and then waits for the user to enter the password. On exiting Truecrypt, it then launches my menu-program. My Lenovo Miix 2 8" tablet, win8.1 (all up to date) will wait, my Dad's win8.0 (all up to date) will wait, but my friend's ASUS M80TA 8" win8.1 tablet (all up to date) will not. Another friend's win7 laptop (all

问题 So someone asked me to write an app for him that logs starts and stop, bssid, local ip, ssid and start/stop time when he connects to a WiFi access point. I did this by: public void onReceive(Context context, Intent intent) { ConnectivityManager connManager = (ConnectivityManager) context .getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo mWifi = connManager .getNetworkInfo(ConnectivityManager.TYPE_WIFI); TelephonyManager telephonyManager = (TelephonyManager)context.getSystemService

问题 I'm writing a simple program to better understand fork(), wait(), and execvp(). My problem is that after I run the program, control is not passed back to the shell and I have no clue why. What I want is to be able to input another command into the shell after the code is finished. I took a look at this, but I don't think it's applicable in my case. I've basically just the copied code I found from here. input/output (# is in front of lines I typed, though is not part of the input): shell> #

问题 I simply want this program to wait for a timer. All I want is for the program to pause for two seconds. I want this program to do is display "Start," wait for two seconds until the timer has finished, then display "Start, Finished Waiting, Finished." How can I make this program wait for the timer to finish? I believe that it currently creates the timer in a separate thread, not pausing the main thread, so it displays,"Start, Finished" then waits for two seconds and then displays "Start,

问题 I need to delay my program's execution for a specified number of milliseconds, but also want the user to be able to escape the wait when a key is pressed. If no key is pressed the program should wait for the specified number of milliseconds. I have been using Thread.Sleep to halt the program (which in the context of my program I think is ok as the UI is set to minimise during the execution of the main method). I have thought about doing something like this: while(GetAsyncKeyState(System

问题 The code I've witten doesn't work as I expected. static Integer sync = 1; static void m() throws Exception { synchronized (sync) { System.err.println("First"); sync.notify(); sync.wait(1000L); System.err.println("Second"); System.err.println("Third"); } } public static void main(String[] args) throws Exception { Runnable r = new Runnable() { @Override public void run() { try { m(); } catch (Exception ex) { Logger.getLogger(IO.class.getName()).log(Level.SEVERE, null, ex); } } }; Runnable t =

问题 I'm implementing the following Java interface to allow threads to be paused and resumed. I've a working version that uses wait()/notifyAll(), but I wondered if there was an easier way to do it (say, using some nifty widget in java.util.concurrent)? public interface Suspender { /** * Go into pause mode: any threads which subsequently call maybePause() * will block. Calling pause() if already in pause mode has no effect. */ void pause(); /** * Leave pause mode: any threads which call maybePause

问题 I'm trying to handle multiple connections on the same port of my server. I'm doing this by instantiating an Object and passing it into the constructor for another class, which implements Runnable. Then I set up a socket in the Runnable class and call notify() on the passed Object after a Client connects on the port. This should then allow the server to restart its loop, creating another instance of the Runnable class after being notified. However, currently the wait() isnt being reached until

问题 What happens when you call notifyAll method on an object that is not waiting? Should there be exception or is it normal situation? 回答1: It is completely normal. You can only notify all that waiting on one single monitor. Everybody else is not interested. The object on which you call notifyAll is just the monitor on which others are waiting. If nobody is waiting nobody has to be notified 回答2: As you can see here, calling notifyAll() on an not waiting object does not have any effect. 回答3: The