Is there a way without using multiple threads?
I found this https://stackoverflow.com/a/17329626/4014896
But i don't get how it works. Shouldn't it cause 100% CPU usage in the example?
and how can I embed it, for example, into QT?
there is also this: https://github.com/svalaskevicius/qt-event-dispatcher-libuv
But there is no documentation at all.
But from my looks it seems to be something that translates from example QSocket to uv_tcp_socket which is not what I'm searching for.
In short - you'll either need to merge the two event loops or use separate threads and sync the event handlers manually..
The first link you pasted shows how to process libuv events that have happened since the last invocation. The while stated there will use ~100% CPU if there are no events dispatched (as it will just keep polling).
The second link (qt-event-dispatcher-libuv) is a project I've created to tackle the same problem. It does, however, work as you described - by using libuv to handle Qt's event loop (and by doing that - merges the two event loops into one).
To use it you'd just need to register the event dispatcher in your application using http://qt-project.org/doc/qt-5/qcoreapplication.html#setEventDispatcher. An example where this library is used - https://github.com/svalaskevicius/qtjs-generator/blob/master/src/runner/main.cpp#L179
There is still one catch using this approach - while it works very well on linux, there are some problems on OS X as the Qt's Cocoa platform support plugin handles some Cocoa's event loop operations and doesn't provide a nice API to merge it as well (currently its updating them one its freed up after a small timeout so there is some (barely?) noticeable lag to handle the GUI events) - I was planning to port the platform support plugin to be able to integrate it as well but that's still in future. And I haven't tested it on windows yet :)
An alternative solution could probably be to try to merge the two loops from another direction that I've done - instead of making Qt to use libuv, libuv's api could be provided that uses Qt's handlers - although it requires a considerable amount of work as well.
Please let me know if there is any more info I could provide.
Regards,
Related
I found many languages provides some way to change code runtime. Many people ask queries regarding how to change code in this or that language runtime. Here I mean by change code is that rewrite code itself at runtime by using reflection or something else.
I have around 6 year of experience in Java application development. I never come again any problem where I have to change code at time.
Can anyone explain why we require to change code at runtime?
I have experienced three huge benefits of changing code at runtime:
Fixing bugs in a production environment without shutting down the application server. This allowed us to fix bugs on just some part of the application without interrupting the whole system.
Possibility of changing the business rule without having to deploy a new version of the application. A quicker deploy of features.
Writing unit test is easier. For example, you can mock dependencies, add some desired behaviour to some objects and etc. Spock Framework does well this.
Of course, we had this benefits because we have a very well defined development process on how to proceed on this situations.
At times you may need to call a method based on the input, that was received earlier in the program.
It could be used for dynamic calculation of value based on the key index, where every key is calculated in a different way or calculation requires fetching required data from different sources. Instead of using switch statement you can invoke a method dynamically using methodName+indexOfTheKey.
I was wondering if it is possible to use Julia to perform computations on a webpage in an automated way.
For example suppose we have a 3x3 html form in which we input some numbers. These form a square matrix A, and we can find its eigenvalues in Julia pretty straightforward. I would like to use Julia to make the computation and then return the results.
In my understanding (which is limited in this direction) I guess the process should be something like:
collect the data entered in the form
send the data to a machine which has Julia installed
run the Julia code with the given data and store the result
send the result back to the webpage and show it.
Do you think something like this is possible? (I've seen some stuff using HttpServer which allows computation with the browser, but I'm not sure this is the right thing to use) If yes, which are the things which I need to look into? Do you have any examples of such implementations of web calculations?
If you are using or can use Node.js, you can use node-julia. It has some limitations, but should work fine for this.
Coincidentally, I was already mostly done with putting together an example that does this. A rough mockup is available here, which uses express to serve the pages and plotly to display results (among other node modules).
Another option would be to write the server itself in Julia using Mux.jl and skip server-side javascript entirely.
Yes, it can be done with HttpServer.jl
It's pretty simple - you make a small script that starts your HttpServer, which now listens to the designated port. Part of configuring the web server is that you define some handlers (functions) that are invoked when certain events take place in your app's life cycle (new request, error, etc).
Here's a very simple official example:
https://github.com/JuliaWeb/HttpServer.jl/blob/master/examples/fibonacci.jl
However, things can get complex fast:
you already need to perform 2 actions:
a. render your HTML page where you take the user input (by default)
b. render the response page as a consequence of receiving a POST request
you'll need to extract the data payload coming through the form. Data sent via GET is easy to reach, data sent via POST not so much.
if you expose this to users you need to setup some failsafe measures to respawn your server script - otherwise it might just crash and exit.
if you open your script to the world you must make sure that it's not vulnerable to attacks - you don't want to empower a hacker to execute random Julia code on your server or access your DB.
So for basic usage on a small case, yes, HttpServer.jl should be enough.
If however you expect a bigger project, you can give Genie a try (https://github.com/essenciary/Genie.jl). It's still work in progress but it handles most of the low level work allowing developers to focus on the specific app logic, rather than on the transport layer (Genie's author here, btw).
If you get stuck there's GitHub issues and a Gitter channel.
Try Escher.jl.
This enables you to build up the web page in Julia.
I am currently trying to use the "Invocation tags" of Mate to call my web services and delegate the WS-responses to my fault/result handlers.
I want to use the generated proxies, provided by the Flex Builder, and not the plain <WebService> or <WebServiceInvoker> tags.
I actually failed using several techniques:
<WebServiceInvoker> does not work with the generated proxies.
<AsyncMethodInvoker> needs some complicated successType that I could not get to work with the WS-calls. And defining the events seems redundant to me. I want it simple and easy to read, the code will be touched by other people than me!
<MethodInvoker> can't use instances, and it also can't handle the proxies' AsyncToken
<DelegateInvoker> Looked fine at first. It calls the service but doesn't fire valid result events (infinite busy cursor). Even though i can successfully bind to the XYZ_lastResult of the WS-proxies, and a WS-call results in getting valid data from the WS-backend, the <faultHandlers> and <resulthandlers> are not executed. There is some solution for the DelegateInvoker that changes code in the generated proxies, which i definately do not want to do!
So here is my question: Is there a simple(!) way of using default Flexbuilder generated proxies with the Mate Invocation tags?
It appears that your request is not that uncommon to Mate. Check out this couple of threads in their forum:
http://mate.asfusion.com/forums/topic.php?id=424
http://mate.asfusion.com/forums/topic.php?id=421
The solution is to modify some bits of the auto-generated code... which in a way ruins the whole point of using code generation.
An existing (though incomplete) FLEX3 project was given to us to finish (always a nightmare).
It is quite small but highly abstracted (contains well over 150 files to support only about 10 page views). I'm attempting to trace a single mouseclick event through this maze.
Is there a way to print out an actionscript trace and/or component flow using the debugger (or any other tool that anyone knows of)?
The flash.txt file appears worthless since it doesn't contain ActionScript calls and/or component flows.
Thanks
This will print your execution graph:
Trace.setLevel(Trace.METHODS, Trace.LISTENER);
Trace.setListener(handleMethods);
function handleMethods(fqcn:String, lineNumber:uint, methodName:String, methodArguments:String):void
{
trace(methodName);
}
Oof. Yeah, always.
The Profiler might give you useful information, but you need to pay for FlexBuilder Pro to get it, if you don't already have it. I'm not real handy with the Profiler, so I may be off base with that advice. It would be worth checking into, though, if you are already familiar with other profiling tools.
I would probably just start looking at every point that .addEventListener(MouseEvent.CLICK occurs in the code - and .addEventListener("click", just in case the previous developer chose not to use the constant, for some reason.
Obviously, that could show up a lot in 150 files, but that's how I would go about it.
I would also look at any custom events that could get into the mix. Because maybe the CLICK event is handled at some point and the handler dispatches a custom event. And maybe the handler for that custom event dispatches another custom event. Or dispatches a MouseEvent.CLICK event, etc.
Hope that helps. Good luck...
Check out
http://jpauclair.net/2010/02/10/mmcfg-treasure/
esp.
AS3Trace = 1|0
This one is also very useful for
debugging It trace every single call
to any function that is being called
in the SWF at runtime! It’s like
expending the StackTrace to the full
software run time.
And many more.
I've been working on a Flex component and I'd like to write some automated tests for it. The trouble is, the UI testing tools I've looked at (FlexMonkey and Selenium Flex API) don't simulate "enough":
Most of the bugs which have come up so far relate to the way Flex deals with dragging and dropping, which these libraries can't simulate accurately enough. For example, I need to test a case where there is a "drop" event which occurs in the bottom half of a component – neither FlexMonkey nor Selenium Flex API can do that (they may simulate a mouse event, but they won't include coordinates).
So, is there any "good" way to automate that sort of testing?
Edit: After much research, it looks like the only piece of software that can do this is iMacros, which is Windows-only and the interface is... Lacking. So I'm going to be writing my own. Basically, it will put an HTTP interface on java.awt.Robot so code (in any language) can simulate mouse/keyboard events. If you're interested, PM me and I'll keep you updated.
Edit 2: I have published the first version of the framework I wrote, Blunderbuss, over at BitBucket: http://bitbucket.org/wolever/blunderbuss/ . You'll need Jython to run it (http://www.jython.org/), but after that the flex-client example should work.
Videos of Blunderbuss live over at Vimeo:
Automating Flex testing with Blunderbuss
Blunderbuss test suite running
At the moment this remains a proof-of-concept, as I haven't had the cycles to clean it up and make it more useable… But maybe enough people bothering me would give me that time :)
I've used Eggplant to test Flash and AIR apps without having to add any hooks into the code. It's a great tool but it's quite expensive. It simulates a real user by VNC-ing into a system and uses image recognition - among other things - to interact with the app.
I am definitely interested in your custom Java class, and (though I am not the best at Java (yet...)), I would be willing to help out if you're thinking of making this collaborative.
As to Flash MouseEvents. Unfortunately, there really isn't an accurate way to simulate the drag/drop experience in Flash. MouseEvents, when generated by the mouse, are handled in a very different way than regular events and while you could simulate actions by passing events into the handling functions, or by making the dispatcher fire a new DragEvent( DragEvent.DRAG_DROP..., it will not be the same as having the user interact with it. And for some functionality (like gaining access to the clipboard), nothing inside Flash will accomplish your goals.
To be honest, you're probably headed in the right direction -- using something which is not written in Flash to drive faked mouse events is probably your best bet.
I've never had to use it in Flex but i recently stumbled across some info on automation packages in the MS Surface SDK... after looking into it those classes automated user behavior which can be used for testing i.e. move a fake mouse to this point, perform this action. As you're using Flex mx.automation packages and classes. My guess (and hope) is that you'd be able to achieve what you want using these classes.
You could also try auto-hotkey - it is similarly a macro-editing program but it has proven to be very efficient and you can write scripts and set it up very easily.