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  • Find messages from certain key till certain key while being able to remove stale keys.

    - by Alfred
    My problem Let's say I add messages to some sort of datastructure: 1. "dude" 2. "where" 3. "is" 4. "my" 5. "car" Asking for messages from index[4,5] should return: "my","car". Next let's assume that after a while I would like to purge old messages because they aren't useful anymore and I want to save memory. Let's say at time x messages[1-3] became stale. I assume that it would be most efficient to just do the deletion once every x seconds. Next my datastructure should contain: 4. "my" 5. "car" My solution? I was thinking of using a concurrentskiplistset or concurrentskiplist map. Also I was thinking of deleting the old messages from inside a newSingleThreadScheduledExecutor. I would like to know how you would implement(efficiently/thread-safe) this or maybe use a library?

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  • C# WinForms populating TreeView from List<myObj>

    - by user743354
    I have this structure of classes: public class L3Message { public int Number { get; set; } public string MessageName { get; set; } public string Device { get; set; } public string Time { get; set; } public string ScramblingCode { get; set; } public List<Parameter> Parameters { get; set; } public L3Message() { Parameters = new List<Parameter>(); } } public class Parameter { public int numOfWhitespaces { get; set; } public string ParameterName { get; set; } public string ParameterValue { get; set; } public Parameter Parent { get; set; } public List<Parameter> SubParameters { get; set; } public Parameter() { SubParameters = new List<Parameter>(); } } So, as return type from one of my Methods I have List of L3Messages (List < L3Message ), and I need to map that to TreeView in WinForms (populate TreeView from that List). If possible, I would like to that in separate thread. How can I achieve that?

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  • Creating a OS X Cocoa App Web View in Xcode 5.0.1

    - by user1822824
    I created a HTML5 web app that I’m trying to wrap in a web view and submit to the Mac App Store. I’ve done the following: 1) Opened Xcode 5.0.1 and selected “Create a new Xcode project” 2) Under “OS X” I selected “Application” then I selected “Cocoa Application” then “Next” 3) I entered a “Product Name” and a “Company Identifier” then selected “Next” (I left all the other settings untouched) then “Create” 4) Under “General” “Deployment Info” “Deployment Target” I selected 10.6 — because I want the app to be compatible with all versions of OS X that support the Mac App Store 5) I clicked “MainMenu.xib” and selected “Window - My App” 6) From the “Object library” I drug the “Web View” object into my window and made it fill the window size 7) I saved my project and click the Play button in the upper left corner of Xcode The app tries to open but freezes. I don’t get an error in Xcode but it does open “main.m” and highlight “return NSApplicationMain(argc, argv);” in green and says “Thread 1: signal SIGABRT” I was hoping that someone could clarify why this isn’t working? And provide me with the last step to link the web view object? I searched Google and found tutorials for iOS and a few for OS X but for different versions of Xcode.

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  • Limiting object allocation over multiple threads

    - by John
    I have an application which retrieves and caches the results of a clients query. The client then requests different chunks of data and the application sends the relevant results and removes them from the cache. A new requirement for this application is that there needs to be a run-time configurable maximum number of results which may be cached. I've taken the naive approach and implemented this by using a counter under a lock which is incremented every time a result is cached and decremented whenever a result is removed from the cache. Unfortunately, this has drastically reduced the applications performance when processing a large number of concurrent requests. I have tried both a critical section lock and spin-lock; the performance improves a bit with a spin-lock, but is still unacceptably slow. Is there a better way to solve this problem which may improve performance? Right now I have a thread pool that services requests and each request is tied to a Request object which stores that cached results for that particular request. Here is a simplified pseudo code version of my current implementation: void ResultCallback( Result result, Request *request ) { lock totalResultsCached lock cachedLimit if( totalResultsCached + 1 > cachedLimit ) { unlock cachedLimit unlock totalResultsCached //cancel the request return; } ++totalResultsCached; unlock cachedLimit unlock totalResultsCached request.add(result) } void SendResults( int resultsToSend, Request *request ) { while ( resultsToSend > 0 ) { send(request.remove()) lock totalResultsCached --totalResultsCached unlock totalResultsCached --resultsToSend; } }

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  • Reading PDF form field data from Flex 4 ( via php or coldfusion )

    - by Brian Russel Davis
    Been searching web for an answer for this for a MONTH. I am not an expert in Coldfusion. So supposedly this is easy in CF -- but the mark-up confuses the HECK out of me. So here I am. I have managed to import and read a PDF using the CF Proxy for Actionscript: http://forums.adobe.com/thread/754629?tstart=0 --- BUT --- After all my trouble there, the precious form filed information that I was looking for was not there in the PDF info object. GRRRR. So I am back to looking for a way to do this with CFC's or CFM's or PHP. All I want is this: Read the PDF from a Flex app. GET the form field information. WRITE a new PDF with the form field values. I have found so many close but no cigar options ... and I have tried so many that failed. There are so many free PDF this and that out there. But Adobe seems to reserve the real functionality for themselves. All the free options don't seem to have access to the form data? Anyways I am so exhausted with looking for ways to do this. I need help!

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  • Java: Using GSon incorrectly? (null pointer exception)

    - by Rosarch
    I'm trying to get the hits of a google search from a string of the query. public class Utils { public static int googleHits(String query) throws IOException { String googleAjax = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&q="; String json = stringOfUrl(googleAjax + query); JsonObject hits = new Gson().fromJson(json, JsonObject.class); return hits.get("estimatedResultCount").getAsInt(); } public static String stringOfUrl(String addr) throws IOException { ByteArrayOutputStream output = new ByteArrayOutputStream(); URL url = new URL(addr); IOUtils.copy(url.openStream(), output); return output.toString(); } public static void main(String[] args) throws URISyntaxException, IOException { System.out.println(googleHits("odp")); } } The following exception is thrown: Exception in thread "main" java.lang.NullPointerException at odp.compling.Utils.googleHits(Utils.java:48) at odp.compling.Utils.main(Utils.java:59) What am I doing incorrectly? Should I be defining an entire object for the Json return? That seems excessive, given that all I want to do is get one value. For reference: the returned JSON structure.

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  • WMI to reboot remote machine

    - by Stephen Murby
    I found this code on an old thread to shutdown the local machine: using System.Management; void Shutdown() { ManagementBaseObject mboShutdown = null; ManagementClass mcWin32 = new ManagementClass("Win32_OperatingSystem"); mcWin32.Get(); // You can't shutdown without security privileges mcWin32.Scope.Options.EnablePrivileges = true; ManagementBaseObject mboShutdownParams = mcWin32.GetMethodParameters("Win32Shutdown"); // Flag 1 means we want to shut down the system. Use "2" to reboot. mboShutdownParams["Flags"] = "1"; mboShutdownParams["Reserved"] = "0"; foreach (ManagementObject manObj in mcWin32.GetInstances()) { mboShutdown = manObj.InvokeMethod("Win32Shutdown", mboShutdownParams, null); } } Is it possible to use a similar WMI method to reboot flag"2" a remote machine, for which i only have machine name, not IPaddress. EDIT: I currently have; SearchResultCollection allMachinesCollected = machineSearch.FindAll(); Methods myMethods = new Methods(); string pcName; ArrayList allComputers = new ArrayList(); foreach (SearchResult oneMachine in allMachinesCollected) { //pcName = oneMachine.Properties.PropertyNames.ToString(); pcName = oneMachine.Properties["name"][0].ToString(); allComputers.Add(pcName); MessageBox.Show(pcName + "has been sent the restart command."); Process.Start("shutdown.exe", "-r -f -t 0 -m \" + pcName); } but this doesn't work, and i would prefer WMI going forward.

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  • What database options do I have for the Blackberry?

    - by peeping-jane
    I notice most of the discussions about Blackberry database options are old, and generally not too informative. As of today, March 31st, 2010, what is the best, most universally supported, free database option available for Blackberry developers? I heard SQLite is available for JDE v5, but last I checked, that was still in beta, and I didn't want to commit to developing on a system that is not supported by most of the phones in service. Thing is, I don't see any dates on these claims. For all I know, the announcements I am reading are from 2008. So, I am still on v 4.7. I need to use a relational DB for the app I am developing, but there aren't many resources for DB handling available - or at least resources that are useful to me. I find a lot of "tutorials" that assume you know everything there is to know about Blackberry development, or Java. But no complete classes or anything. Many of these examples don't even work. Eclipse gives warnings and errors from code copied and pasted from other people's examples. I can answer any questions that may assist in this case. Hopefully, this thread will help many BB developers in the future.

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  • .NET: bool vs enum as a method parameter

    - by Julien Lebosquain
    Each time I'm writing a method that takes a boolean parameter representing an option, I find myself thinking: "should I replace this by an enum which would make reading the method calls much easier?". Consider the following with an object that takes a parameter telling whether the implementation should use its thread-safe version or not (I'm not asking here if this way of doing this is good design or not, only the use of the boolean): public void CreateSomeObject(bool makeThreadSafe); CreateSomeObject(true); When the call is next to the declaration the purpose of the parameter seems of course obvious. When it's in some third party library you barely know, it's harder to immediately see what the code does, compared to: public enum CreationOptions { None, MakeThreadSafe } public void CreateSomeObject(CreationOptions options); CreateSomeObject(CreationOptions.MakeThreadSafe); which describes the intent far better. Things get worse when there's two boolean parameters representing options. See what happened to ObjectContext.SaveChanges(bool) between Framework 3.5 and 4.0. It has been obsoleted because a second option has been introduced and the whole thing has been converted to an enum. While it seems obvious to use an enumeration when there's three elements or more, what's your opinion and experiences about using an enum instead a boolean in these specific cases?

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  • The shell dotfile cookbook

    - by Jason Baker
    I constantly hear from other people about how much of the stuff they've used to customize their *nix setup they've shamelessly stolen from other people. So in that spirit, I'd like to start a place to share that stuff here on SO. Here are the rules: DON'T POST YOUR ENTIRE DOTFILE. Instead, just show us the cool stuff. One recipe per answer You may, however, post multiple versions of your recipe in the same answer. For example, you may post a version that works for bash, a version that works for zsh, and a version that works for csh in the same answer. State what shells you know your recipe will work with in the answer. Let's build this cookbook as a team. If you find out that an answer works with other shells other than the one the author posted, edit it in. If you like an idea and rewrite it to work with another shell, edit the modified version in to the original post. Give credit where credit is due. If you got your idea from someone else, give them credit if possible. And for those of you (justifiably) asking "Why do we need another one of these threads?": Most of what I've seen is along the lines of "post your entire dotfile." Personally, I don't want to try to parse through a person's entire dotfile to figure out what I want. I just want to know about all the cool parts of it. It's helpful to have a single dotfile thread. I think most of the stuff that works in bash will work in zsh and it may be adapted to work with csh fairly easily.

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  • android use local service to refresh map UI

    - by urobo
    I don't need a strict code related answer I just need somebody to tell me what I am missing. My application has to retrieve from a web service (xmlrpc) the positions of some users I know and update their position on a MapView. So I decided to use a Service and an Activity extending MapActivity to show results. I thought about two solutions: I ) start the service and make it ask every minute for these positions and send them to the activity as a bundle via intent. (This didn't work out well, since once shown I couldn't find a method to let the activity continue refresh itself until she stop receiving intents+data from the service) II ) Incorporate a thread within the activity which starts the service via context.startService(...) every minute. And the MapUI refresh itself once the service send back an intent and stop itself. (Maybe I will fall in the same problem category as before I haven't tryied yet). I am also giving directions (via maps.google ws) in this way I'd like to refresh only users positions on the map and save the route. What Am I missing do you have any suggestions? related to activities/services internal mechanics, don't know launch modes, use broadcast receivers or intent filters? Thanks in advance

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  • A question about TBB/C++ code

    - by Jackie
    I am reading The thread building block book. I do not understand this piece of code: FibTask& a=*new(allocate_child()) FibTask(n-1,&x); FibTask& b=*new(allocate_child()) FibTask(n-2,&y); What do these directive mean? class object reference and new work together? Thanks for explanation. The following code is the defination of this class FibTask. class FibTask: public task { public: const long n; long* const sum; FibTask(long n_,long* sum_):n(n_),sum(sum_) {} task* execute() { if(n FibTask& a=*new(allocate_child()) FibTask(n-1,&x); FibTask& b=*new(allocate_child()) FibTask(n-2,&y); set_ref_count(3); spawn(b); spawn_and_wait_for_all(a); *sum=x+y; } return 0; } };

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  • Input In Java- How does it work?

    - by Nir Avnon
    Hey guys, with a lot of help from you i was managed to write this nice code (I'm new in it, so kind of exciting.. :) ) And still I have not understand how can I input this code. first of all, I get an this error in the console line (I'm using Eclipse): Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0 at NumberConverter.main(NumberConverter.java:5). What does that mean? I just want to chack whether it works, and I can't call the function/program any how. I used to call in an "old fashion way", like in scheme, to the function that I wrote and see if something happens. How does it work in java? Do we call the program itself? function? what and where do we write? -I want to chack if it works, doesn't matter how, and I'll be glad to know how can I plugin input. Thank you so much! public class NumberConverter{ public static void main(String[] args) { int i = Integer.parseInt(args[0]); toBinary(i); toOctal(i); toHex(i); } public static void toBinary(int int1){ System.out.println(int1 + " in binary is"); System.out.println(Integer.toBinaryString(int1)); } public static void toOctal(int int1){ System.out.println(int1 + " in octal is"); System.out.println(Integer.toOctalString(int1)); } public static void toHex(int int1){ System.out.println(int1 + " in hex is"); System.out.println(Integer.toHexString(int1)); } }

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  • Multithreading for loop while maintaining order

    - by David
    I started messing around with multithreading for a CPU intensive batch process I'm running. Essentially I'm trying to condense multiple single page tiffs into single PDF documents. This works fine with a foreach loop or standard iteration but can be very slow for several 100 page documents. I tried the following based on a some examples I found to use multithreading and it has significant performance improvements however it obliterates the page order instead of 1,2,3,4 it will be 1,3,4,2,6,5 on what thread completes first. My question is how would I utilize this technique while maintaining the page order and if I can will it negate the performance benefit of the multithreading? Thank you in advance. PdfDocument doc = new PdfDocument(); string mail = textBox1.Text; string[] split = mail.Split(new string[] { Environment.NewLine }, StringSplitOptions.None); int counter = split.Count(); // Source must be array or IList. var source = Enumerable.Range(0, 100000).ToArray(); // Partition the entire source array. var rangePartitioner = Partitioner.Create(0, counter); double[] results = new double[counter]; // Loop over the partitions in parallel. Parallel.ForEach(rangePartitioner, (range, loopState) => { // Loop over each range element without a delegate invocation. for (int i = range.Item1; i < range.Item2; i++) { f_prime = split[i].Replace(" " , ""); PdfPage page = doc.AddPage(); XGraphics gfx = XGraphics.FromPdfPage(page); XImage image = XImage.FromFile(f_prime); double x = 0; gfx.DrawImage(image, x, 0); } });

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  • cuda 5.0 namespaces for contant memory variable usage

    - by Psypher
    In my program I want to use a structure containing constant variables and keep it on device all long as the program executes to completion. I have several header files containing the declaration of 'global' functions and their respective '.cu' files for their definitions. I kept this scheme because it helps me contain similar code in one place. e.g. all the 'device' functions required to complete 'KERNEL_1' are separated from those 'device' functions required to complete 'KERNEL_2' along with kernels definitions. I had no problems with this scheme during compilation and linking. Until I encountered constant variables. I want to use the same constant variable through all kernels and device functions but it doesn't seem to work. ########################################################################## CODE EXAMPLE ########################################################################### filename: 'common.h' -------------------------------------------------------------------------- typedef struct { double height; double weight; int age; } __CONSTANTS; __constant__ __CONSTANTS d_const; --------------------------------------------------------------------------- filename: main.cu --------------------------------------------------------------------------- #include "common.h" #include "gpukernels.h" int main(int argc, char **argv) { __CONSTANTS T; T.height = 1.79; T.weight = 73.2; T.age = 26; cudaMemcpyToSymbol(d_consts, &T, sizeof(__CONSTANTS)); test_kernel <<< 1, 16 >>>(); cudaDeviceSynchronize(); } --------------------------------------------------------------------------- filename: gpukernels.h --------------------------------------------------------------------------- __global__ void test_kernel(); --------------------------------------------------------------------------- filename: gpukernels.cu --------------------------------------------------------------------------- #include <stdio.h> #include "gpukernels.h" #include "common.h" __global__ void test_kernel() { printf("Id: %d, height: %f, weight: %f\n", threadIdx.x, d_const.height, d_const.weight); } When I execute this code, the kernel executes, displays the thread ids, but the constant values are displayed as zeros. How can I fix this?

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  • Looping through a method without for/foreach/while

    - by RichK
    Is there a way of calling a method/lines of code multiple times not using a for/foreach/while loop? For example, if I were to use to for loop: int numberOfIterations = 6; for(int i = 0; i < numberOfIterations; i++) { DoSomething(); SomeProperty = true; } The lines of code I'm calling don't use 'i' and in my opinion the whole loop declaration hides what I'm trying to do. This is the same for a foreach. I was wondering if there's a looping statement I can use that looks something like: do(6) { DoSomething(); SomeProperty = true; } It's really clear that I just want to execute that code 6 times and there's no noise involving index instantiating and adding 1 to some arbitrary variable. As a learning exercise I have written a static class and method: Do.Multiple(int iterations, Action action) Which works but scores very highly on the pretentious scale and I'm sure my peers wouldn't approve. I'm probably just being picky and a for loop is certainly the most recognisable, but as a learning point I was just wondering if there (cleaner) alternatives. Thanks. (I've had a look at this thread, but it's not quite the same) http://stackoverflow.com/questions/2248985/using-ienumerable-without-foreach-loop

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  • java.lang.IllegalStateException: The content of the adapter has changed but ListView.... inspite of calling notifydatasetchanged()

    - by Mistaken
    What are the best practices to be followed to update the contents of a listactivty by a background thread (Async Task) ? 1) Am calling the notifyDataSetChanged() to update the adapter as soon as i manipulate the contents of the adapter but still my app force closes while the user scrolls or click on the list. Any pointers to prevent this would be very helpfull. Logcat: java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. 2) Where exaclty should i update contents of the listactivity ? inside the doInBackground() or onProgressUpdate()? 3) Am experiencing regular crashes when the user clicks the list item. So will disabling click events on the listactivty during the background operation solve the problem ? If so am not sure how to remove or set item click listeners dynamically to the listactivity. Please instruct me on the too. 4) I dont think blocking all ui interactions during the background async task execution is the only way to solve the problem. I know there is a simple way of doing this but need some help. Thanks in advance. This is my onCreate... protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.fa); tvStatus=(TextView) findViewById(R.id.tvStatus); adapter = new SimpleAdapter( this, mostPopularList, R.layout.list_item, new String[] {"title","author","views","date"}, new int[] {R.id.textView1,R.id.textView2,R.id.textView4,R.id.textView3}); //populateList(); setListAdapter(adapter); } My async task... private class LongOperation extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... params) { // code for adding new listactivty items } @Override protected void onPostExecute(String networkStatus) { adapter.notifyDataSetChanged(); } @Override protected void onPreExecute() { } @Override protected void onProgressUpdate(Void... values) { } }

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  • This process does not work in JavaScript: createElement() -> setAttribute('id') -> getElementById()

    - by kristovaher
    I was so sure that this question has been answered a thousand times before, but I've been unable to find an answer in StackOverflow. If there is already an answer and I was unable to find it then I apologize. I create hidden form elements dynamically like this: submitForm=document.getElementById('my-form'); var element=document.createElement('input'); element.id='hidden-form-data'; // or setAttribute('id','hidden-form-data'); element.name='my-hidden-form-data'; element.type='hidden'; element.value='my-data'; submitForm.appendChild(element); This works and the input field is created and it is taken into account when submitting the form. But I want to remove it after I have dynamically created it. I was sure that creating a new node this way would be 'correct' for browser and DOM, but apparently it is not. This returns null: element=document.getElementById('hidden-form-data'); if(element!=null){ element.parentNode.removeChild(element); } But it never gets removed and is always null. Is there any way I can remove a dynamically created node with an ID? Thank you! Please do not suggest jQuery, it's not possible to use jQuery for this, footprint is too heavy for such a small task I could not get a working answer from here, which was the closest thread I could find.

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  • GTK+ with any programs

    - by user565739
    I recently knew a latex-editor "gummi", see http://gummi.midnightcoding.org/ , which is written by GTK+ graphical interface toolkit. There are two panels, one in the left which is an editor (using the library gtksourceview) and on in the right which is a viewer (using the library poppler). I am curious that if we can do similary things for every program. For example, replace the editor with "terminal"?"emacs"?"vim"?"terminator (a multi-windows terminal)"...etc. And replace the viewer with other viewers, which in my mind is Adobe Reader. With discussion with the author, he mentioned: The viewer component is also replacable, but doing it with Adobe Reader would not be easy or perhaps even impossible. The reason for this being that Adobe Reader is a complete program instead of a library, and also closed-source So I have some questions: a) We can only make "library" embedded as a panel, but we can't do this for a (any) program? b) Could we replace the editor with emacs? with terminal? c) Could we replace the viewer with Adobe Reader? If not, why? Because it's a program or it's closed-source? I know the questions in this thread are not very precise, sorry.

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  • Could someone help me debug my app (not very big)?

    - by Alex
    Not sure if this kind of help is accepted to ask for here, tell me if it isn't. It has to get done before tomorrow, it's not entirerly finished but it should work somewhat ok by now. I'm trying to use the Eclipse debugger (not very used to it). I have my top-level or main class, which is Game, in which I have a constructor and a main method. In the main method I create a new "Game", initiating the constructor. public static void main(String[] args){ Game chess = new Game(); } public Game(){ Board board = new Board(); That's the first thing the debugger reacts to: Thread [main] (Suspended) ClassNotFoundException(Object).<init>() line: 20 [local variables unavailable] ClassNotFoundException(Throwable).<init>(String, Throwable) line: 217 ClassNotFoundException(Exception).<init>(String, Throwable) line: not available ClassNotFoundException.<init>(String) line: not available URLClassLoader$1.run() line: not available AccessController.doPrivileged(PrivilegedExceptionAction<T>, AccessControlContext) line: not available [native method] Launcher$ExtClassLoader(URLClassLoader).findClass(String) line: not available Launcher$ExtClassLoader.findClass(String) line: not available Launcher$ExtClassLoader(ClassLoader).loadClass(String, boolean) line: not available Launcher$AppClassLoader(ClassLoader).loadClass(String, boolean) line: not available Launcher$AppClassLoader.loadClass(String, boolean) line: not available Launcher$AppClassLoader(ClassLoader).loadClass(String) line: not available Game.<init>() line: 15 Game.main(String[]) line: 11 Line 11 is the one line in my main method, line 15 is the instantiation of "board".

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  • Using multiple Qt (SQL) Models

    - by radix07
    I have a near real-time application that I am using Qt and an SQLite database to run. I am curious if it is safe to have two separate models access a database at once. I know 2 separate views can access a model just fine, but I can't find any document addressing this. I also realize that SQLite is thread safe for reading, so I don't see a real issue to doing this from the SQLite part of things... Basically I want to use a QSqlTableModel to do the real-time read and write in the background and at the same time use a QSqlQueryModel to give the user desired data. Since I may be doing lots of filtering in the background using the table model I can't use it as the main view as well. I have gotten this to work for the most part, but am not sure if this is the best way to do this. If the models act like multiple SQL queries I don't believe this should be an issue, but I would like to know from someone I bit more knowledgeable about this stuff since this is pretty new to me. Thanks

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  • Does the Java Memory Model (JSR-133) imply that entering a monitor flushes the CPU data cache(s)?

    - by Durandal
    There is something that bugs me with the Java memory model (if i even understand everything correctly). If there are two threads A and B, there are no guarantees that B will ever see a value written by A, unless both A and B synchronize on the same monitor. For any system architecture that guarantees cache coherency between threads, there is no problem. But if the architecture does not support cache coherency in hardware, this essentially means that whenever a thread enters a monitor, all memory changes made before must be commited to main memory, and the cache must be invalidated. And it needs to be the entire data cache, not just a few lines, since the monitor has no information which variables in memory it guards. But that would surely impact performance of any application that needs to synchronize frequently (especially things like job queues with short running jobs). So can Java work reasonably well on architectures without hardware cache-coherency? If not, why doesn't the memory model make stronger guarantees about visibility? Wouldn't it be more efficient if the language would require information what is guarded by a monitor? As i see it the memory model gives us the worst of both worlds, the absolute need to synchronize, even if cache coherency is guaranteed in hardware, and on the other hand bad performance on incoherent architectures (full cache flushes). So shouldn't it be more strict (require information what is guarded by a monitor) or more lose and restrict potential platforms to cache-coherent architectures? As it is now, it doesn't make too much sense to me. Can somebody clear up why this specific memory model was choosen? EDIT: My use of strict and lose was a bad choice in retrospect. I used "strict" for the case where less guarantees are made and "lose" for the opposite. To avoid confusion, its probably better to speak in terms of stronger or weaker guarantees.

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  • NullPointerException on Activity Testint Tutorial

    - by Bendik
    Hello, I am currently trying the activity testing tutorial (Found here), and have a problem. It seems that whenever I try to call something inside the UIThread, I get a java.lang.NullPointerException. public void testSpinnerUI() { mActivity.runOnUiThread( new Runnable() { public void run() { mSpinner.requestFocus(); } }); } This gives me: Incomplete: java.lang.NullPointerException and nothing else. I have tried this on two different samples now, with the same result. I tried with a try/catch clause around the mSpinner.requestFocus() call, and it seems that mSpinner is null inside the thread. I have set it properly up with the setUp() function found in the same sample, and a quick assertNotNull( mSpinner ) shows me that mSpinner is in fact not null after the setUp() function. What can be the cause of this? EDIT; ok, some more testing has been done. It seems that the application that is being tested resets between each test. This essentially makes me have to reinstantiate all variables between each test. Is this normal?

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  • implementing interface

    - by 1ace1
    hello guys so i have this assignment that i need to implement interface to go over an ArrayList and sort it (ascending or descnding).I dont want "the" answer i just need some suggestions on my approach and why i get this error Exception in thread "main" java.lang.ClassCastException: Week7.Check cannot be cast to java.lang.Comparable at java.util.Arrays.mergeSort(Unknown Source) at java.util.Arrays.sort(Unknown Source) at java.util.Collections.sort(Unknown Source) at Week7.TestCheck.main(TestCheck.java:18) This is how i did it: comparable had one method called public int compairTo(Object o) public class Check implements comparable { private Integer checkNumber; public Check(Integer newCheckNumber) { setCheckNumber(newCheckNumber); } public String toString() { return getCheckNumber().toString(); } public void setCheckNumber(Integer checkNumber) { this.checkNumber = checkNumber; } public Integer getCheckNumber() { return checkNumber; } @Override public int compairTo(Object o) { Check compair = (Check)o; int result = 0; if (this.getCheckNumber() > compair.getCheckNumber()) result = 1; else if(this.getCheckNumber() < compair.getCheckNumber()) result = -1; return result; } } in my main i had this import java.util.ArrayList; import java.util.Collections; public class TestCheck { public static void main(String[] args) { ArrayList checkList = new ArrayList(); checkList.add(new Check(445)); checkList.add(new Check(101)); checkList.add(new Check(110)); checkList.add(new Check(553)); checkList.add(new Check(123)); Collections.sort(checkList); for (int i =0; i < checkList.size(); i++){ System.out.println(checkList.get(i)); } } }

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  • jQuery - making sure content is loaded before it's faded in?

    - by Kenny Bones
    Hi, Nick Craver really helped me out alot with this code in this thread http://stackoverflow.com/questions/2743443/jquery-can-someone-help-stitching-jquery-code-with-ajaxcomplete/2743791#2743791 And it is working. But I notice that there's a small delay after I've clicked a link and before the content is actually loaded. It's not very intense content that's loaded either so I think it's got something to do with the order which things happen in the script. The original code looks like this: $('.dynload').live('click', function(){ var toLoad = $(this).attr('href')+' #content'; $('#content').fadeOut('fast',loadContent); $('#ajaxloader').fadeIn('normal'); function loadContent() { $('#content').load(toLoad,'',showNewContent()) } function showNewContent() { $('#content').fadeIn('fast',hideLoader()); //Cufon.replace('h1, h2, h3, h4, .menuwrapper', { fontFamily: 'advent'}); } function hideLoader() { $('#ajaxloader').fadeOut('normal'); } return false; }); The new code looks like this: $(function() { $('.dynload').live('click', function(){ $('#ajaxloader').fadeIn('fast'); $('#ajaxloaderfridge').fadeIn('fast'); var href = this.href + ' #content'; $('#content').fadeOut('fast',function() { $(this).load(href,'', function(data) { createMenus(); $('#ajaxloader').fadeOut('fast'); $('#ajaxloaderfridge').fadeOut('fast'); $('#content').fadeIn('fast'); Cufon.replace('h1, h2, h3, h4, .menuwrapper', { fontFamily: 'advent'}); }); }); return false; }); }); $(createMenus); function createMenus() { $('#kontrollpanel .slidepanels').kwicks({ min : 42, spacing : 3, isVertical : true, sticky : true, event : 'click' }); } In the original code, #content is faded out, then the function "loadContent" is started. Which is basically what is happening in the new script as well isn't it? And when I was using the old code, the content just faded out and faded in really fast and smooth and with no small pause delay before the content arrived.

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