asynchronous

问题 Our application has some code that runs asynchronously that is failing. Like this: CompletableFuture.runAsync( () -> { throw new RuntimeException("bad"); }, executorService ); We want default exception handling code that can catch these errors, in case specific uses forget to handle exceptions (this came from a production bug). This is apparently tricky. The answer given in Handling exceptions from Java ExecutorService tasks does not work. It relies on the task being a Future<?> and then

问题 I have web application and it calls different web service to perform different work. Some web services will take long time and some short. Application will call all web services parallel to get result when complete or exception. I have started to write code but i need to know how to implement the following works in the best way. A task will be cancelled if any of web service takes more than 5 seconds but remaining tasks will continue to call web service to get either result or excepton. I

问题 I am using a library (pouchDB) that does some async operations. To keep things simple, I will keep the details out of it as I think this is a general issue with "unit testing" involving async operations (unit testing in quotation marks because I guess this isn't truly unit testing if I am testing integration with another library. But, using QUnit seems like the most appropriate way to write tests for it). I am using QUnit to do my js unit testing. I have two tests. I am finding that if I run

问题 In my Vuejs app I need to pass two computed properties to a component called avatar : an image surce and a string. The problem is that not all items have a picture, and when they don't, vuejs throws an error because it cannot read property apples of undefined (because album_id is undefined). The error is being thrown from that very long-winded src property in the avatar component, below: <template> <div class="apples"> <div id="mast" class="f3 b bb b--black-10"> <h2 class="ttc">Apple's List<

问题 I'm currently struggling to make an interop call work because I can't synchronously wait for a Promise in javascript. Before you think about closing this as duplicate, note that I have done some searching and I understand that it says everywhere it's not possible to synchronously wait for a Promise. Once async, always async. Source(s): How to wait for a JavaScript Promise to resolve before resuming function?, How can I synchronously determine a JavaScript Promise's state?, Call An

问题 Where should we ideally place an api call to be made on occurrence of an event in React Inside the eventHandler or componentDidUpdate ? example: handleItemClick = (item) => (event) => { this.setState({selectedItem: item}); this.props.requestDataActionDispatch(item); } OR componentDidUpdate(prevProps, prevState, snapshot) { if(prevState.item !== this.state.item) { this.props.requestDataActionDispatch(item); } } 回答1: Depends But a simple solution is, if you want to call some API after change of

问题 I have this code doing what I want: TriggerSomeExternalProcess(); double secondsElapsed = 0; DateTime startTime = DateTime.UtcNow; double timeoutInSeconds = 10; while (secondsElapsed < timeoutInSeconds) { // TODO: this seems bad... secondsElapsed = DateTime.UtcNow.Subtract(startTime).TotalSeconds; } CheckStatusOfExternalProcess(); The goal is to TriggerSomeExternalProcess and then CheckStatusOfSomeExternalProcess - but that process runs on the same thread so I can't do Thread.Sleep() . It's

问题 There are tons of examples of how to wait for a thread to exit, but sometimes i need to wait just until several threads are "ready" or have reached certain milestone. After reading: What's the proper way to wait for a .NET thread to start up? and http://www.albahari.com/threading/ If i have understood correctly: Wait for one Child Task to be ready : //Main Method var wh = new AutoResetEvent(false); Task childTask = Task.Run(() => ChildTask(wh); wh.WaitOne(); //Child private void ChildTask

问题 I have a simple asynchronous socket server written in C# (pretty much Microsoft's example), however the issue with this example is that it accepts only one message from a client and then shuts down. I want this server to stay alive after receiving any message. This question has been asked before here, and the answer & comments explain that the resolution to this is simply to call handler.beginReceive within the SendCallback function, however to do this requires passing in a state variable.

问题 I am developing a windows service that is able to receive socket connection, so in the OnStart method: protected override void OnStart(string[] args) { start(); } The start function looks like this: public async void Start() { //initialization things ... ... TcpListener listener = new TcpListener(IPAddress.Any, port); listener.Start(); while(true) { TcpClient client = await listener.AcceptTcpClientAsync().ConfigureAwait(false); ... } ... } The problem is that no connection is accepted, while