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Android threads can't get notify() to work properly using wait() and notify()

java,android,multithreading,wait,notify
So I am writing an Android application which will do a count down when the user presses a button. A thread runs the count down. My problem is that when I pause the application I want the thread to stop counting and then resume once the application is back. My...

linux -c - notify the kernel from userspace as fast as possible and vice versa

c,linux,linux-kernel,mmap,notify
Context : Debian 64 bits. Making a linux-only userspace networking stack that I may release open source. Everything is ready but one last thing. The problem : I know about poll/select/epoll and use them heavily already but they are too complicated for my need and tend to add latency (few...

Notify update of Tooltip Value (wpf)

wpf,xaml,binding,datagrid,notify
I have a Datagrid structure in xaml and several columns inside it: <DataGridTextColumn x:Name="QualityValueColumn" Binding="{Binding QualityValue}"> <DataGridTextColumn.CellStyle> <Style TargetType="DataGridCell"> <Setter Property="ToolTip" Value="{Binding MySelf, Converter={StaticResource ItemToTooltipConverter}}"/> <Setter Property="ToolTipService.ShowDuration" Value="48000"></Setter> <Setter Property="BorderThickness" Value="0"></Setter> </Style>...

Exception in thread “AWT-EventQueue-0” java.lang.IllegalMonitorStateException at java.lang.Object.notify(Native Method)

java,jdialog,notify
What I'm trying to do: Launch a window to request parameters What I've tried: If I remove the vp.wait(), the window disappears. If I remove notify(), the program doesn`t wait. Here's my code: public static void main(String[] args) throws InterruptedException{ if(args.length==0){ ParamsWind vp = new ParamsWind(); vp.setVisible(true); synchronized (vp){ try...

Java: coding basic multithreading

java,multithreading,wait,notify
I'm writing a rhythm game in Java; right now I've reached the point where I'm trying to implement a metronome object. I've coded a data structure that stores 8 channels of music data into a single QuarterBeat object; these are in turn stored in groups of 64 to make 4-measure...

java.lang.IllegalMonitorStateException whilst calling wait from synchronized block

java,multithreading,wait,notify
Before I move onto using Condition variables I'm trying to understand object wait principles. I wrote a little code to understand more but its not working as expected. What is supposed to happen is a Waiter class waits upon thread start. Meanwhile the Notifier class adds some elements to a...

Wait and Notify in Java threads for a given interval

java,multithreading,thread-safety,wait,notify
i am working on a usecase as below. I am new to multi threading and facing this issue with using it. I broadcast a event on network. Its received by all the listeners, and they unicast me with their information. This is received inside the call back method as below,...

How can a loop be completed by two thread? say loop from count=1 to count=4 by ist thread and count =5 to 8 by 2nd thread?

java,multithreading,wait,notify
Description of how i want the output : I want two threads Gaurav and john to complete a while loop(from 1 to 8), such that whichever thread starts ist, runs for 5 iterations(i.e. till count=5) , then go to sleep and then next thread completes the loop (run for count=6...

Linux - c - ipc notification without context switch and low overhead?

c,linux,ipc,notify,low-latency
Context : Linux 64bits. I am very well versed in shared memories, different IPCs mechanisms. Currently, I am seeking something that could be used in userspace to notify change between two polled processes, to save cpu cycles. I already know about futexes, eventfd, slow signals and even char devices. But...

how to decide the looping condition for wait() in Java

java,multithreading,wait,notify
I am understanding wait() in Java in regards to multithreaded, and as per the documentation, wait() should always be in a loop. I have difficult in understanding what is the condition we have to give in the loop. Typically, I have seen: synchornized(obj) { while(some_condition) { obj.wait(); } // some...

Program gets halted: wait() and notify()

java,multithreading,wait,synchronized,notify
I am trying to achieve this: Created two different threads, one prints odd numbers, one prints even numbers. Once one thread prints a number, it has to wait for the other thread and so on, that is one-after-other. To achieve this, i am using synchronized block along with wait() and...

How to notify thread of changes

java,apache-commons,notify
I have created a class FolderObserver which observes a folder in my project for changes (file created/file deleted). My class is implementing the Runnable interface (I'm using the classes FileAlterationObserver, FileAlterationMonitor, FileAlterationListener from apache commons). In my main class I start a thread with my FolderObserver object as an argument....

dijit/Tree is not updated when connected to a dojo/store/JsonRest

dynamic,dojo,notify,dijit.tree,jsonreststore
I have modified the dojo tutorial at http://dojotoolkit.org/documentation/tutorials/1.10/store_driven_tree/demo/demo.html to read from a JsonRest store. The problem is that the tree display doesn't update when I click "Add new child to selected item" e.g. on the root element, although the update worked in the original tutorial. I have compared what dojo/store/Memory...