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  • IE8 v8 not changing class for a DOM element despite JS function changing the element attribute

    - by Alfabravo
    I have an on-screen keyboard in order to provide a safer input for passwords. The keyboard itself is placed like this: <div class="teclado_grafico" id="teclado_grafico"> <a class="tecla_teclado" onmousedown="teclaAction( this, 'caja_selector'); return false" style="top: 0px; left: 0px;">Q</a> <a class="tecla_teclado" onmousedown="teclaAction( this, 'caja_selector'); return false" style="top: 0px; left: 28px;">W</a> . . . </div> And it has a "Shift button" which fires a JS function with this (I've already tried all that, indeed): if (obj.innerHTML == "Mayus.") { try { MAYUSCULA_ACTIVADO = !MAYUSCULA_ACTIVADO; var tgrafico = document.getElementById("teclado_grafico"); if(MAYUSCULA_ACTIVADO) { // tgrafico.className = "teclado_grafico mayuscula"; // $("#teclado_grafico").removeClass('minuscula').addClass('mayuscula'); // $("#teclado_grafico").attr('class', 'teclado_grafico mayuscula'); // $("#teclado_grafico").attr('className', 'teclado_grafico mayuscula'); tgrafico.setAttribute('className', "teclado_grafico mayuscula") || tgrafico.setAttribute('class', "teclado_grafico mayuscula"); } else { // tgrafico.className = "teclado_grafico minuscula"; // $("#teclado_grafico").removeClass('mayuscula').addClass('minuscula'); // $("#teclado_grafico").attr('class', 'teclado_grafico minuscula'); // $("#teclado_grafico").attr('className', 'teclado_grafico minuscula'); tgrafico.setAttribute('className', "teclado_grafico minuscula") || tgrafico.setAttribute('class', "teclado_grafico minuscula"); } } catch (_E) { //void } return; } The associated CSS is like this: .mayuscula a.tecla_teclado{ text-transform: uppercase; } .minuscula a.tecla_teclado{ text-transform: lowercase; } It works on every single browser I've tried. IE 6, 7; Opera 10; GChrome; FF 3, 3.5 and 3.6; Safari 4,... but in IE8 v8 (strict mode) the class is not changed! I mean, debuggin' with the IE8 tools allows one to see that the attribute className is there and it changes... but the user does not see the letters changing from uppercase to lowercase, to uppercase again. I just don't know how to handle this... I had complains about the client using IE6... now they updated their stuff and this shows up. Any help will be reaaaaly helpful!

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  • cannot evaluate expression because a native frame is on top of the call stack and system.accessviolationexception

    - by Joseph
    I have this code using c#. public partial class MainForm : Form { private CvCapture VideoCapture; private IplImage frame; private IplImage imgMain; public MainForm() { InitializeComponent(); } private void btnVideo_Click(object sender, EventArgs e) { double vidWidth, vidHeight; try { VideoCapture = highgui.CvCreateCameraCapture(0); } catch (Exception except) { MessageBox.Show(except.Message); } if (btnVideo.Text.CompareTo("Start Video") == 0) { if (VideoCapture.ptr == IntPtr.Zero) { MessageBox.Show("badtrip ah!!!"); return; } btnVideo.Text = "Stop Video"; highgui.CvSetCaptureProperty(ref VideoCapture, highgui.CV_CAP_PROP_FRAME_WIDTH, 640); highgui.CvSetCaptureProperty(ref VideoCapture, highgui.CV_CAP_PROP_FRAME_HEIGHT, 480); highgui.CvQueryFrame(ref VideoCapture); vidWidth = highgui.cvGetCaptureProperty(VideoCapture, highgui.CV_CAP_PROP_FRAME_WIDTH); vidHeight = highgui.cvGetCaptureProperty(VideoCapture, highgui.CV_CAP_PROP_FRAME_HEIGHT); picBoxMain.Width = (int)vidWidth; picBoxMain.Height = (int)vidHeight; timerGrab.Enabled = true; timerGrab.Interval = 42; timerGrab.Start(); } else { btnVideo.Text = "Start Video"; timerGrab.Enabled = false; if (VideoCapture.ptr == IntPtr.Zero) { highgui.CvReleaseCapture(ref VideoCapture); VideoCapture.ptr = IntPtr.Zero; } } } private void timerGrab_Tick(object sender, EventArgs e) { try { frame = highgui.CvQueryFrame(ref VideoCapture); if (frame.ptr == IntPtr.Zero) { timerGrab.Stop(); MessageBox.Show("??"); return; } imgMain = cxcore.CvCreateImage(cxcore.CvGetSize(ref frame), 8, 3); picBoxMain.Image = highgui.ToBitmap(imgMain, false); cxcore.CvReleaseImage(ref imgMain); //cxcore.CvReleaseImage(ref frame); } catch (Exception excpt) { MessageBox.Show(excpt.Message); } } } The problem is after i break all and step through the debugger the program stops at a certain code. the code where it stops is here: frame = highgui.CvQueryFrame(ref VideoCapture); the error is that it says that cannot evaluate expression because a native frame is on top of the call stack. and then when i try to shift+F11 it. there is another error saying that system.accessviolationexception. the stack trace says that: at System.Runtime.InteropServices.Marshal.CopyToManaged(IntPtr source, Object destination, Int32 startIndex, Int32 length) at CxCore.IplImage.get_ImageDataDb()

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  • .NET RegEx "Memory Leak" investigation

    - by Kevin Pullin
    I recently looked into some .NET "memory leaks" (i.e. unexpected, lingering GC rooted objects) in a WinForms app. After loading and then closing a huge report, the memory usage did not drop as expected even after a couple of gen2 collections. Assuming that the reporting control was being kept alive by a stray event handler I cracked open WinDbg to see what was happening... Using WinDbg, the !dumpheap -stat command reported a large amount of memory was consumed by string instances. Further refining this down with the !dumpheap -type System.String command I found the culprit, a 90MB string used for the report, at address 03be7930. The last step was to invoke !gcroot 03be7930 to see which object(s) were keeping it alive. My expectations were incorrect - it was not an unhooked event handler hanging onto the reporting control (and report string), but instead it was held on by a System.Text.RegularExpressions.RegexInterpreter instance, which itself is a descendant of a System.Text.RegularExpressions.CachedCodeEntry. Now, the caching of Regexs is (somewhat) common knowledge as this helps to reduce the overhead of having to recompile the Regex each time it is used. But what then does this have to do with keeping my string alive? Based on analysis using Reflector, it turns out that the input string is stored in the RegexInterpreter whenever a Regex method is called. The RegexInterpreter holds onto this string reference until a new string is fed into it by a subsequent Regex method invocation. I'd expect similar behaviour by hanging onto Regex.Match instances and perhaps others. The chain is something like this: Regex.Split, Regex.Match, Regex.Replace, etc Regex.Run RegexScanner.Scan (RegexScanner is the base class, RegexInterpreter is the subclass described above). The offending Regex is only used for reporting, rarely used, and therefore unlikely to be used again to clear out the existing report string. And even if the Regex was used at a later point, it would probably be processing another large report. This is a relatively significant problem and just plain feels dirty. All that said, I found a few options on how to resolve, or at least work around, this scenario. I'll let the community respond first and if no takers come forward I will fill in any gaps in a day or two.

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  • Building the WAR with m2eclipse in combination with WTP (handling webResources)

    - by waxwing
    I have a situation where I have a web application that is built using maven (i.e., maven-war-plugin). For each code modification, we have had to manually launch maven and restart the application server. Now, to reduce build cycle overhead, I want to use WTP to publish the webapp. Now, we have resource processing with Maven, and there are some additional Maven tasks defined in our POM when building the webapp. Therefore m2eclipse seems like a natural solution. I have gotten far enough that the Maven builder is running these tasks and filtering resources correctly. However, when I choose "Run on Server", the WAR file does not look like it would if I built it in Maven. I am guessing that this is because WTP actually builds the WAR, and not the m2eclipse builder. So even though we have configured the maven-war-plugin in our POM, those settings are not used. Below is a snippet with our maven-war-plugin configuration. What is configured under "webResources" is not picked up, it appears: <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-war-plugin</artifactId> <version>2.1-alpha-2</version> <configuration> <outputDirectory>${project.build.directory}</outputDirectory> <workDirectory>${project.build.directory}/work</workDirectory> <webappDirectory>${project.build.webappDirectory}</webappDirectory> <cacheFile>${project.build.webappDirectory}/webapp-cache.xml</cacheFile> <filteringDeploymentDescriptors>true</filteringDeploymentDescriptors> <nonFilteredFileExtensions> <nonFilteredFileExtension>pdf</nonFilteredFileExtension> <nonFilteredFileExtension>png</nonFilteredFileExtension> <nonFilteredFileExtension>gif</nonFilteredFileExtension> <nonFilteredFileExtension>jsp</nonFilteredFileExtension> </nonFilteredFileExtensions> <webResources> <!-- Add generated WSDL:s and XSD:s for the web service api. --> <resource> <directory>${project.build.directory}/jaxws/wsgen/wsdl</directory> <targetPath>WEB-INF/wsdl</targetPath> <filtering>false</filtering> <includes> <include>**/*</include> </includes> </resource> </webResources> </configuration> Do I need to reconfigure these resources to be handled elsewhere, or is there a better solution?

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  • Is this asking too much of a browser?

    - by Matt Ball
    I'm embedding a large array in <script> tags in my HTML, like this (nothing surprising): <script> var largeArray = [/* lots of stuff in here */]; </script> In this particular example, the array has 210,000 elements. That's well below the theoretical maximum of 231 - by 4 orders of magnitude. Here's the fun part: if I save JS source for the array to a file, that file is 44 megabytes (46,573,399 bytes, to be exact). If you want to see for yourself, you can download it from my Dropbox. (All the data in there is canned, so much of it is repeated. This will not be the case in production.) Now, I'm really not concerned about serving that much data. My server gzips its responses, so it really doesn't take all that long to get the data over the wire. However, there is a really nasty tendency for the page, once loaded, to crash the browser. I'm not testing at all in IE (this is an internal tool). My primary targets are Chrome 8 and Firefox 3.6. In Firefox, I can see a reasonably useful error in the console: Error: script stack space quota is exhausted In Chrome, I simply get the sad-tab page: Cut to the chase, already Is this really too much data for our modern, "high-performance" browsers to handle? Is there anything I can do* to gracefully handle this much data? Incidentally, I was able to get this to work (read: not crash the tab) on-and-off in Chrome. I really thought that Chrome, at least, was made of tougher stuff, but apparently I was wrong... Edit 1 @Crayon: I wasn't looking to justify why I'd like to dump this much data into the browser at once. Short version: either I solve this one (admittedly not-that-easy) problem, or I have to solve a whole slew of other problems. I'm opting for the simpler approach for now. @various: right now, I'm not especially looking for ways to actually reduce the number of elements in the array. I know I could implement Ajax paging or what-have-you, but that introduces its own set of problems for me in other regards. @Phrogz: each element looks something like this: {dateTime:new Date(1296176400000), terminalId:'terminal999', 'General___BuildVersion':'10.05a_V110119_Beta', 'SSM___ExtId':26680, 'MD_CDMA_NETLOADER_NO_BCAST___Valid':'false', 'MD_CDMA_NETLOADER_NO_BCAST___PngAttempt':0} @Will: but I have a computer with a 4-core processor, 6 gigabytes of RAM, over half a terabyte of disk space ...and I'm not even asking for the browser to do this quickly - I'm just asking for it to work at all! ? *other than the obvious: sending less data to the browser

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  • Perl Moose::Util::TypeConstraints bug ? what is this error about the name has invalid chars ?

    - by alex8657
    That has been hours i am tracking a Moose::Util::TypeConstraints exceptions, i don't understand where it gets to check a type and tells me that the name is incorrect. I tracked the error to a reduced example to try to locate the problem, and it just shows me that i do not get it. Did i get to a Moose::Util::TypeConstraints bug ? aoffice:new alex$ perl -c ../codesnippets/typeconstrainterror.pl ../codesnippets/typeconstrainterror.pl syntax OK aoffice:new alex$ perl -d ../codesnippets/typeconstrainterror.pl (...) DB<1> r Something::File::LocalFile=HASH(0x100d1bfa8) contains invalid characters for a type name. Names can contain alphanumeric character, ":", and "." at /opt/local/lib/perl5/vendor_perl/5.10.1/darwin-multi-2level/Moose/Util/TypeConstraints.pm line 508 Moose::Util::TypeConstraints::_create_type_constraint('Something::File::LocalFile=HASH(0x100d1bfa8)', undef, undef, undef, undef) called at /opt/local/lib/perl5/vendor_perl/5.10.1/darwin-multi-2level/Moose/Util/TypeConstraints.pm line 285 Moose::Util::TypeConstraints::type('Something::File::LocalFile=HASH(0x100d1bfa8)') called at ../codesnippets/typeconstrainterror.pl line 7 Something::File::is_slink('Something::File::LocalFile=HASH(0x100d1bfa8)') called at ../codesnippets/typeconstrainterror.pl line 33 Debugged program terminated. Use q to quit or R to restart, use o inhibit_exit to avoid stopping after program termination, h q, h R or h o to get additional info. Below, the code that crashes: package Something::File; use Moose; has 'type' =>(is=>'ro', isa=>'Str', writer=>'_set_type' ); sub is_slink { my $self = shift; return ( $self->type eq 'slink' ); } no Moose; __PACKAGE__->meta->make_immutable; 1; package Something::File::LocalFile; use Moose; use Moose::Util::TypeConstraints; extends 'Something::File'; subtype 'PositiveInt' => as 'Int' => where { $_ >0 } => message { 'Only positive greater than zero integers accepted' }; no Moose; __PACKAGE__->meta->make_immutable; 1; my $a = Something::File::LocalFile->new; # $a->_set_type('slink'); print $a->is_slink ." end\n";

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  • How to make efficient code emerge through unit testing

    - by Jean
    Hi, I participate in a TDD Coding Dojo, where we try to practice pure TDD on simple problems. It occured to me however that the code which emerges from the unit tests isn't the most efficient. Now this is fine most of the time, but what if the code usage grows so that efficiency becomes a problem. I love the way the code emerges from unit testing, but is it possible to make the efficiency property emerge through further tests ? Here is a trivial example in ruby: prime factorization. I followed a pure TDD approach making the tests pass one after the other validating my original acceptance test (commented at the bottom). What further steps could I take, if I wanted to make one of the generic prime factorization algorithms emerge ? To reduce the problem domain, let's say I want to get a quadratic sieve implementation ... Now in this precise case I know the "optimal algorithm, but in most cases, the client will simply add a requirement that the feature runs in less than "x" time for a given environment. require 'shoulda' require 'lib/prime' class MathTest < Test::Unit::TestCase context "The math module" do should "have a method to get primes" do assert Math.respond_to? 'primes' end end context "The primes method of Math" do should "return [] for 0" do assert_equal [], Math.primes(0) end should "return [1] for 1 " do assert_equal [1], Math.primes(1) end should "return [1,2] for 2" do assert_equal [1,2], Math.primes(2) end should "return [1,3] for 3" do assert_equal [1,3], Math.primes(3) end should "return [1,2] for 4" do assert_equal [1,2,2], Math.primes(4) end should "return [1,5] for 5" do assert_equal [1,5], Math.primes(5) end should "return [1,2,3] for 6" do assert_equal [1,2,3], Math.primes(6) end should "return [1,3] for 9" do assert_equal [1,3,3], Math.primes(9) end should "return [1,2,5] for 10" do assert_equal [1,2,5], Math.primes(10) end end # context "Functionnal Acceptance test 1" do # context "the prime factors of 14101980 are 1,2,2,3,5,61,3853"do # should "return [1,2,3,5,61,3853] for ${14101980*14101980}" do # assert_equal [1,2,2,3,5,61,3853], Math.primes(14101980*14101980) # end # end # end end and the naive algorithm I created by this approach module Math def self.primes(n) if n==0 return [] else primes=[1] for i in 2..n do if n%i==0 while(n%i==0) primes<<i n=n/i end end end primes end end end

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  • Scipy Negative Distance? What?

    - by disappearedng
    I have a input file which are all floating point numbers to 4 decimal place. i.e. 13359 0.0000 0.0000 0.0001 0.0001 0.0002` 0.0003 0.0007 ... (the first is the id). My class uses the loadVectorsFromFile method which multiplies it by 10000 and then int() these numbers. On top of that, I also loop through each vector to ensure that there are no negative values inside. However, when I perform _hclustering, I am continually seeing the error, "Linkage Z contains negative values". I seriously think this is a bug because: I checked my values, the values are no where small enough or big enough to approach the limits of the floating point numbers and the formula that I used to derive the values in the file uses absolute value (my input is DEFINITELY right). Can someone enligten me as to why I am seeing this weird error? What is going on that is causing this negative distance error? ===== def loadVectorsFromFile(self, limit, loc, assertAllPositive=True, inflate=True): """Inflate to prevent "negative" distance, we use 4 decimal points, so *10000 """ vectors = {} self.winfo("Each vector is set to have %d limit in length" % limit) with open( loc ) as inf: for line in filter(None, inf.read().split('\n')): l = line.split('\t') if limit: scores = map(float, l[1:limit+1]) else: scores = map(float, l[1:]) if inflate: vectors[ l[0]] = map( lambda x: int(x*10000), scores) #int might save space else: vectors[ l[0]] = scores if assertAllPositive: #Assert that it has no negative value for dirID, l in vectors.iteritems(): if reduce(operator.or_, map( lambda x: x < 0, l)): self.werror( "Vector %s has negative values!" % dirID) return vectors def main( self, inputDir, outputDir, limit=0, inFname="data.vectors.all", mappingFname='all.id.features.group.intermediate'): """ Loads vector from a file and start clustering INPUT vectors is { featureID: tfidfVector (list), } """ IDFeatureDic = loadIdFeatureGroupDicFromIntermediate( pjoin(self.configDir, mappingFname)) if not os.path.exists(outputDir): os.makedirs(outputDir) vectors = self.loadVectorsFromFile( limit, pjoin( inputDir, inFname)) for threshold in map( lambda x:float(x)/30, range(20,30)): clusters = self._hclustering(threshold, vectors) if clusters: outputLoc = pjoin(outputDir, "threshold.%s.result" % str(threshold)) with open(outputLoc, 'w') as outf: for clusterNo, cluster in clusters.iteritems(): outf.write('%s\n' % str(clusterNo)) for featureID in cluster: feature, group = IDFeatureDic[featureID] outline = "%s\t%s\n" % (feature, group) outf.write(outline.encode('utf-8')) outf.write("\n") else: continue def _hclustering(self, threshold, vectors): """function which you should call to vary the threshold vectors: { featureID: [ tfidf scores, tfidf score, .. ] """ clusters = defaultdict(list) if len(vectors) > 1: try: results = hierarchy.fclusterdata( vectors.values(), threshold, metric='cosine') except ValueError, e: self.werror("_hclustering: %s" % str(e)) return False for i, featureID in enumerate( vectors.keys()):

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  • Advice on logic circuits and serial communications

    - by Spencer Ruport
    As far as I understand the serial port so far, transferring data is done over pin 3. As shown here: There are two things that make me uncomfortable about this. The first is that it seems to imply that the two connected devices agree on a signal speed and the second is that even if they are configured to run at the same speed you run into possible synchronization issues... right? Such things can be handled I suppose but it seems like there must be a simpler method. What seems like a better approach to me would be to have one of the serial port pins send a pulse that indicates that the next bit is ready to be stored. So if we're hooking these pins up to a shift register we basically have: (some pulse pin)-clk, tx-d Is this a common practice? Is there some reason not to do this? EDIT Mike shouldn't have deleted his answer. This I2C (2 pin serial) approach seems fairly close to what I did. The serial port doesn't have a clock you're right nobugz but that's basically what I've done. See here: private void SendBytes(byte[] data) { int baudRate = 0; int byteToSend = 0; int bitToSend = 0; byte bitmask = 0; byte[] trigger = new byte[1]; trigger[0] = 0; SerialPort p; try { p = new SerialPort(cmbPorts.Text); } catch { return; } if (!int.TryParse(txtBaudRate.Text, out baudRate)) return; if (baudRate < 100) return; p.BaudRate = baudRate; for (int index = 0; index < data.Length * 8; index++) { byteToSend = (int)(index / 8); bitToSend = index - (byteToSend * 8); bitmask = (byte)System.Math.Pow(2, bitToSend); p.Open(); p.Parity = Parity.Space; p.RtsEnable = (byte)(data[byteToSend] & bitmask) > 0; s = p.BaseStream; s.WriteByte(trigger[0]); p.Close(); } } Before anyone tells me how ugly this is or how I'm destroying my transfer speeds my quick answer is I don't care about that. My point is this seems much much simpler than the method you described in your answer nobugz. And it wouldn't be as ugly if the .Net SerialPort class gave me more control over the pin signals. Are there other serial port APIs that do?

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  • Java Hardware Acceleration

    - by Freezerburn
    I have been spending some time looking into the hardware acceleration features of Java, and I am still a bit confused as none of the sites that I found online directly and clearly answered some of the questions I have. So here are the questions I have for hardware acceleration in Java: 1) In Eclipse version 3.6.0, with the most recent Java update for Mac OS X (1.6u10 I think), is hardware acceleration enabled by default? I read somewhere that someCanvas.getGraphicsConfiguration().getBufferCapabilities().isPageFlipping() is supposed to give an indication of whether or not hardware acceleration is enabled, and my program reports back true when that is run on my main Canvas instance for drawing to. If my hardware acceleration is not enabled now, or by default, what would I have to do to enable it? 2) I have seen a couple articles here and there about the difference between a BufferedImage and VolatileImage, mainly saying that VolatileImage is the hardware accelerated image and is stored in VRAM for fast copy-from operations. However, I have also found some instances where BufferedImage is said to be hardware accelerated as well. Is BufferedImage hardware accelerated as well in my environment? What would be the advantage of using a VolatileImage if both types are hardware accelerated? My main assumption for the advantage of having a VolatileImage in the case of both having acceleration is that VolatileImage is able to detect when its VRAM has been dumped. But if BufferedImage also support acceleration now, would it not have the same kind of detection built into it as well, just hidden from the user, in case that the memory is dumped? 3) Is there any advantage to using someGraphicsConfiguration.getCompatibleImage/getCompatibleVolatileImage() as opposed to ImageIO.read() In a tutorial I have been reading for some general concepts about setting up the rendering window properly (tutorial) it uses the getCompatibleImage method, which I believe returns a BufferedImage, to get their "hardware accelerated" images for fast drawing, which ties into question 2 about if it is hardware accelerated. 4) This is less hardware acceleration, but it is something I have been curious about: do I need to order which graphics get drawn? I know that when using OpenGL via C/C++ it is best to make sure that the same graphic is drawn in all the locations it needs to be drawn at once to reduce the number of times the current texture needs to be switch. From what I have read, it seems as if Java will take care of this for me and make sure things are drawn in the most optimal fashion, but again, nothing has ever said anything like this clearly. 5) What AWT/Swing classes support hardware acceleration, and which ones should be used? I am currently using a class that extends JFrame to create a window, and adding a Canvas to it from which I create a BufferStrategy. Is this good practice, or is there some other type of way I should be implementing this? Thank you very much for your time, and I hope I provided clear questions and enough information for you to answer my several questions.

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  • Release Process Improvements

    - by wallismark
    The process of creating a new build and releasing it to production is a critical step in the SDLC but it is often left as an afterthought and varies greatly from one company to the next. I'm hoping people will share improvements they have made to this process in their organisation so we can all takes steps to 'reduce the pain'. So the question is, specify one painful/time consuming part of your release process and what did you do to improve it? My example: at a previous employer all developers made database changes on one common development database. Then when it came to release time, we used Redgate's SQL Compare to generate a huge script from the differences between the Dev and QA databases. This works reasonably well but the problems with this approach are:- ALL changes in the Dev database are included, some of which may still be 'works in progress'. Sometimes developers made conflicting changes (that were not noticed until the release was in production) It was a time consuming and manual process to create and validate the script (by validate I mean, try to weed out issues like problem 1 and 2). When there were problems with the script (eg the order in which things were run such as creating a record which relies on a foreign key record which is in the script but not yet run) it took time to 'tweak' it so it ran smoothly. It's not an ideal scenario for Continuous Integration. So the solution was:- Enforce a policy of all changes to the database must be scripted. A naming convention was important for ensuring the correct running order of the scripts. Create/Use a tool to run the scripts at release time. Developers had their own copy of the database do develop against (so there was no more 'stepping on each others toes') The next release after we started this process was much faster with fewer problems, indeed the only problems found were due to people 'breaking the rules', eg not creating a script. Once the issues with releasing to QA were fixed, when it came time to release to production it was very smooth. We applied a few other changes (like introducing CI) but this was the most significant, overall we reduced release time from around 3 hours down to a max of 10-15 minutes.

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  • Can Hudson branch promotion get based on project stability?

    - by Wayne
    Hudson CI server displays stability "weather" which is cool. And it allows one project build to kick off based on the successful build of another. However, how can you make that secondary project dependent additionally on the stability of multiple builds of the first project? Specifically, project "stable_deploy" needs to only kick off to promote a version to "stable" if project "integrate" with version 8.3.4.1233 has built and tested successfully at least 8 times--in a row. Until then, it's still in integration mode. IMPORTANT: A significant caveat to this is that a single set of Hudson projects gets used as a "pipeline" to process each new version through to release. So a project may have built successfully 8 times in a rolw but the latest version 8.3.4.1233 may be only the 2 most recent builds. The builds prior to that may be an earlier version. We're open to completely reorganizing this but the pipeline idea seemed to greatly reduce the amount of manually project creation and deletion. Is there a better way to track version release "pipeline"? In particular, we will have multiple versions in this pipeline simultaneously in the future due to fixes or patches to older versions. We don't see how to do that yet, except to create new pipeline projects for each version which is a real hassle. Here's some background details: The TickZoom application has some very complete unit tests some of which simulates real time trading environments. Add to that TickZoom makes elaborate use of parallelization for leveraging multi-core computers. Needless to say, during development of a new version, there can be stability issues during integration testing which get uncovered by running the build and auto tests repeatedly. A version which builds and tests cleanly 8 times in a row without change plus has undergone some real world testing by users can be deemed "stable" and promoted to the stable branch. Our Hudson projects look like this: test - Only for testing a build, zero user visibility. integrate_deploy - Promotes a test project build to integrate branch and makes it available to public for UA testing. integrate - Repeatedly builds the integrate branch to determine if it's stable enough to promote to stable branch. This runs the builds and test hourly throughout every night. stable_deploy - Promotes an integrate project build to the stable branch and makes it public for users who want the latest and greatest. stable - Builds the stable branch once every night. After 2 weeks of successful builds (14 builds) it can go to "release candidate". And so on... it continues with "release candidate" and then "release".

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  • Efficiency of data structures in C99 (possibly affected by endianness)

    - by Ninefingers
    Hi All, I have a couple of questions that are all inter-related. Basically, in the algorithm I am implementing a word w is defined as four bytes, so it can be contained whole in a uint32_t. However, during the operation of the algorithm I often need to access the various parts of the word. Now, I can do this in two ways: uint32_t w = 0x11223344; uint8_t a = (w & 0xff000000) >> 24; uint8_t b = (w & 0x00ff0000) >> 16; uint8_t b = (w & 0x0000ff00) >> 8; uint8_t d = (w & 0x000000ff); However, part of me thinks that isn't particularly efficient. I thought a better way would be to use union representation like so: typedef union { struct { uint8_t d; uint8_t c; uint8_t b; uint8_t a; }; uint32_t n; } word32; Using this method I can assign word32 w = 0x11223344; then I can access the various parts as I require (w.a=11 in little endian). However, at this stage I come up against endianness issues, namely, in big endian systems my struct is defined incorrectly so I need to re-order the word prior to it being passed in. This I can do without too much difficulty. My question is, then, is the first part (various bitwise ands and shifts) efficient compared to the implementation using a union? Is there any difference between the two generally? Which way should I go on a modern, x86_64 processor? Is endianness just a red herring here? I could inspect the assembly output of course, but my knowledge of compilers is not brilliant. I would have thought a union would be more efficient as it would essentially convert to memory offsets, like so: mov eax, [r9+8] Would a compiler realise that is what happening in the bit-shift case above? If it matters, I'm using C99, specifically my compiler is clang (llvm). Thanks in advance.

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  • Alternatives to requiring users to register for an account?

    - by jamieb
    I'm working on a side project to build a new web app idea of mine. For the sake of discussion, let's say this app displays a random photograph of a famous work of art. On a scale of 1 to 5, users are asked to rate how well they like each piece of art, and then are shown the next photo. Eventually, the app is able to get an sense of the person's style and is able to recommend artwork that he/she may find pleasing. The whole concept is similar to Netflix. I understand how to do all the preference matching logic (although not as sophisticated as Netflix). But I'd like to find a way to do this without requiring that users create an account first. This is a novelty website that a typical user might use only a handful of times. Requiring registration is overkill and will likely drastically reduce it's utility. I'd like to allow people to begin rating artwork within five seconds of their initial pageview, yet maintain the integrity of the voting (since recommendations are predicated on how other people have rated the various pieces of artwork). Can it be done? Some ideas: OpenID. The perfect solution except for the fact that it's not wildly used and my target audience isn't the most technically adept demographic. Text message. User inputs phone number and is texted a four digit code to key into the web app. Quick, easy, and great way to limit abuse. However, privacy concerns abound... people are probably even less likely to give me their phone number than their email address. Facebook login. I personally don't have a Facebook account due to privacy concerns. And I'd really hate to support such a proprietary platform. Hash code/Bookmark. Vistor's initial pageview generates a 5 or 6 digit alphanumeric code that is embedded in each subsequent URL. They can bookmark any page to save their state. Good: Very simple system that doesn't require any user action. Bad: Very easy to stuff the ballot box, might be difficult to account for users sharing the link containing their ID code via email or social networking sites.

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  • Bulk inserts into sqlite db on the iphone...

    - by akaii
    I'm inserting a batch of 100 records, each containing a dictonary containing arbitrarily long HTML strings, and by god, it's slow. On the iphone, the runloop is blocking for several seconds during this transaction. Is my only recourse to use another thread? I'm already using several for acquiring data from HTTP servers, and the sqlite documentation explicitly discourages threading with the database, even though it's supposed to be thread-safe... Is there something I'm doing extremely wrong that if fixed, would drastically reduce the time it takes to complete the whole operation? NSString* statement; statement = @"BEGIN EXCLUSIVE TRANSACTION"; sqlite3_stmt *beginStatement; if (sqlite3_prepare_v2(database, [statement UTF8String], -1, &beginStatement, NULL) != SQLITE_OK) { printf("db error: %s\n", sqlite3_errmsg(database)); return; } if (sqlite3_step(beginStatement) != SQLITE_DONE) { sqlite3_finalize(beginStatement); printf("db error: %s\n", sqlite3_errmsg(database)); return; } NSTimeInterval timestampB = [[NSDate date] timeIntervalSince1970]; statement = @"INSERT OR REPLACE INTO item (hash, tag, owner, timestamp, dictionary) VALUES (?, ?, ?, ?, ?)"; sqlite3_stmt *compiledStatement; if(sqlite3_prepare_v2(database, [statement UTF8String], -1, &compiledStatement, NULL) == SQLITE_OK) { for(int i = 0; i < [items count]; i++){ NSMutableDictionary* item = [items objectAtIndex:i]; NSString* tag = [item objectForKey:@"id"]; NSInteger hash = [[NSString stringWithFormat:@"%@%@", tag, ownerID] hash]; NSInteger timestamp = [[item objectForKey:@"updated"] intValue]; NSData *dictionary = [NSKeyedArchiver archivedDataWithRootObject:item]; sqlite3_bind_int( compiledStatement, 1, hash); sqlite3_bind_text( compiledStatement, 2, [tag UTF8String], -1, SQLITE_TRANSIENT); sqlite3_bind_text( compiledStatement, 3, [ownerID UTF8String], -1, SQLITE_TRANSIENT); sqlite3_bind_int( compiledStatement, 4, timestamp); sqlite3_bind_blob( compiledStatement, 5, [dictionary bytes], [dictionary length], SQLITE_TRANSIENT); while(YES){ NSInteger result = sqlite3_step(compiledStatement); if(result == SQLITE_DONE){ break; } else if(result != SQLITE_BUSY){ printf("db error: %s\n", sqlite3_errmsg(database)); break; } } sqlite3_reset(compiledStatement); } timestampB = [[NSDate date] timeIntervalSince1970] - timestampB; NSLog(@"Insert Time Taken: %f",timestampB); // COMMIT statement = @"COMMIT TRANSACTION"; sqlite3_stmt *commitStatement; if (sqlite3_prepare_v2(database, [statement UTF8String], -1, &commitStatement, NULL) != SQLITE_OK) { printf("db error: %s\n", sqlite3_errmsg(database)); } if (sqlite3_step(commitStatement) != SQLITE_DONE) { printf("db error: %s\n", sqlite3_errmsg(database)); } sqlite3_finalize(beginStatement); sqlite3_finalize(compiledStatement); sqlite3_finalize(commitStatement);

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  • INSERT OR IGNORE in a trigger

    - by dan04
    I have a database (for tracking email statistics) that has grown to hundreds of megabytes, and I've been looking for ways to reduce it. It seems that the main reason for the large file size is that the same strings tend to be repeated in thousands of rows. To avoid this problem, I plan to create another table for a string pool, like so: CREATE TABLE AddressLookup ( ID INTEGER PRIMARY KEY AUTOINCREMENT, Address TEXT UNIQUE ); CREATE TABLE EmailInfo ( MessageID INTEGER PRIMARY KEY AUTOINCREMENT, ToAddrRef INTEGER REFERENCES AddressLookup(ID), FromAddrRef INTEGER REFERENCES AddressLookup(ID) /* Additional columns omitted for brevity. */ ); And for convenience, a view to join these tables: CREATE VIEW EmailView AS SELECT MessageID, A1.Address AS ToAddr, A2.Address AS FromAddr FROM EmailInfo LEFT JOIN AddressLookup A1 ON (ToAddrRef = A1.ID) LEFT JOIN AddressLookup A2 ON (FromAddrRef = A2.ID); In order to be able to use this view as if it were a regular table, I've made some triggers: CREATE TRIGGER trg_id_EmailView INSTEAD OF DELETE ON EmailView BEGIN DELETE FROM EmailInfo WHERE MessageID = OLD.MessageID; END; CREATE TRIGGER trg_ii_EmailView INSTEAD OF INSERT ON EmailView BEGIN INSERT OR IGNORE INTO AddressLookup(Address) VALUES (NEW.ToAddr); INSERT OR IGNORE INTO AddressLookup(Address) VALUES (NEW.FromAddr); INSERT INTO EmailInfo SELECT NEW.MessageID, A1.ID, A2.ID FROM AddressLookup A1, AddressLookup A2 WHERE A1.Address = NEW.ToAddr AND A2.Address = NEW.FromAddr; END; CREATE TRIGGER trg_iu_EmailView INSTEAD OF UPDATE ON EmailView BEGIN UPDATE EmailInfo SET MessageID = NEW.MessageID WHERE MessageID = OLD.MessageID; REPLACE INTO EmailView SELECT NEW.MessageID, NEW.ToAddr, NEW.FromAddr; END; The problem After: INSERT OR REPLACE INTO EmailView VALUES (1, '[email protected]', '[email protected]'); INSERT OR REPLACE INTO EmailView VALUES (2, '[email protected]', '[email protected]'); The updated rows contain: MessageID ToAddr FromAddr --------- ------ -------- 1 NULL [email protected] 2 [email protected] [email protected] There's a NULL that shouldn't be there. The corresponding cell in the EmailInfo table contains an orphaned ToAddrRef value. If you do the INSERTs one at a time, you'll see that Alice's ID in the AddressLookup table changes! It appears that this behavior is documented: An ON CONFLICT clause may be specified as part of an UPDATE or INSERT action within the body of the trigger. However if an ON CONFLICT clause is specified as part of the statement causing the trigger to fire, then conflict handling policy of the outer statement is used instead. So the "REPLACE" in the top-level "INSERT OR REPLACE" statement is overriding the critical "INSERT OR IGNORE" in the trigger program. Is there a way I can make it work the way that I wanted?

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  • Queue ExternalInterface calls to Flash Object in UpdatePanel - Needs Improvement?

    - by Laramie
    A Flash (actually Flex) object is created on an ASP.Net page within an Update Panel using a modified version of the embedCallAC_FL_RunContent.js script so it can be written in dynamically. It is re-created with this script with each partial postback to that panel. There are also other Update Panels on the page. With some postbacks (partial and full), External Interface calls such as $get('FlashObj').ExternalInterfaceFunc('arg1', 0, true); are prepared server-side and added to the page using ScriptManager.RegisterStartupScript. They're embedded in a function and stuffed into Sys.Application's load event, for example Sys.Application.add_load(funcContainingExternalInterfaceCalls). The problem is that because the Flash object's state state may change with each partial postback, the Flash (Flex) object and/or External Interface may not be ready or even exist yet in the DOM when the JavaScript - Flash External Interface call is made. It results in an "Object doesn't support this property or method" exception. I have a working strategy to make the ExternalInterface calls immediately if Flash is ready or else queue them until such time that Flash announces its readiness. //Called when the Flash object is initialized and can accept ExternalInterfaceCalls var flashReady = false; //Called by Flash when object is fully initialized function setFlashReady() { flashReady = true; //Make any queued ExternalInterface calls, then dequeue while (extIntQueue.length > 0) (extIntQueue.shift())(); } var extIntQueue = []; function callExternalInterface(flashObjName, funcName, args) { //reference to the wrapped ExternalInterface Call var wrapped = extWrap(flashObjName, funcName, args); //only procede with ExternalInterface call if the global flashReady variable has been set if (flashReady) { wrapped(); } else { //queue the function so when flashReady() is called next, the function is called and the aruments are passed. extIntQueue.push(wrapped); } } //bundle ExtInt call and hold variables in a closure function extWrap(flashObjName, funcName, args) { //put vars in closure return function() { var funcCall = '$get("' + flashObjName + '").' + funcName; eval(funcCall).apply(this, args); } } I set the flashReady var to dirty whenever I update the Update Panel that contains the Flash (Flex) object. ScriptManager.RegisterClientScriptBlock(parentContainer, parentContainer.GetType(), "flashReady", "flashReady = false;", true); I'm pleased that I got it to work, but it feels like a hack. I am still on the learning curve with respect to concepts like closures why "eval()" is apparently evil, so I'm wondering if I'm violating some best practice or if this code should be improved, if so how? Thanks.

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  • Python - wxPython What's wrong?

    - by Wallter
    I am trying to write a simple custom button in wx.Python. My code is as follows,(As a side note: I am relatively new to python having come from C++ and C# any help on syntax and function of the code would be great! - knowing that, it could be a simple error. thanks!) Error Traceback (most recent call last): File "D:\Documents\Python2\Button\src\Custom_Button.py", line 10, in <module> class Custom_Button(wx.PyControl): File "D:\Documents\Python2\Button\src\Custom_Button.py", line 13, in Custom_Button Mouse_over_bmp = wx.Bitmap(0) # When the mouse is over File "C:\Python26\lib\site-packages\wx-2.8-msw-unicode\wx\_gdi.py", line 561, in __init__ _gdi_.Bitmap_swiginit(self,_gdi_.new_Bitmap(*args, **kwargs)) TypeError: String or Unicode type required Main.py class MyFrame(wx.Frame): def __init__(self, parent, ID, title): wxFrame.__init__(self, parent, ID, title, wxDefaultPosition, wxSize(400, 400)) self.CreateStatusBar() self.SetStatusText("Program testing custom button overlays") menu = wxMenu() menu.Append(ID_ABOUT, "&About", "More information about this program") menu.AppendSeparator() menu.Append(ID_EXIT, "E&xit", "Terminate the program") menuBar = wxMenuBar() menuBar.Append(menu, "&File"); self.SetMenuBar(menuBar) self.Button1 = Custom_Button(self, parent, -1, "D:/Documents/Python/Normal.bmp", "D:/Documents/Python/Clicked.bmp", "D:/Documents/Python/Over.bmp", "None", wx.Point(200,200), wx.Size(300,100)) EVT_MENU(self, ID_ABOUT, self.OnAbout) EVT_MENU(self, ID_EXIT, self.TimeToQuit) def OnAbout(self, event): dlg = wxMessageDialog(self, "Testing the functions of custom " "buttons using pyDev and wxPython", "About", wxOK | wxICON_INFORMATION) dlg.ShowModal() dlg.Destroy() def TimeToQuit(self, event): self.Close(true) class MyApp(wx.App): def OnInit(self): frame = MyFrame(NULL, -1, "wxPython | Buttons") frame.Show(true) self.SetTopWindow(frame) return true app = MyApp(0) app.MainLoop() Custom Button import wx from wxPython.wx import * class Custom_Button(wx.PyControl): ############################################ ##THE ERROR IS BEING THROWN SOME WHERE IN HERE ## ############################################ # The BMP's Mouse_over_bmp = wx.Bitmap(0) # When the mouse is over Norm_bmp = wx.Bitmap(0) # The normal BMP Push_bmp = wx.Bitmap(0) # The down BMP Pos_bmp = wx.Point(0,0) # The posisition of the button def __init__(self, parent, NORM_BMP, PUSH_BMP, MOUSE_OVER_BMP, pos, size, text="", id=-1, **kwargs): wx.PyControl.__init__(self,parent, id, **kwargs) # Set the BMP's to the ones given in the constructor self.Mouse_over_bmp = wx.Bitmap(MOUSE_OVER_BMP) self.Norm_bmp = wx.Bitmap(NORM_BMP) self.Push_bmp = wx.Bitmap(PUSH_BMP) self.Pos_bmp = pos ############################################ ##THE ERROR IS BEING THROWN SOME WHERE IN HERE ## ############################################ self.Bind(wx.EVT_LEFT_DOWN, self._onMouseDown) self.Bind(wx.EVT_LEFT_UP, self._onMouseUp) self.Bind(wx.EVT_LEAVE_WINDOW, self._onMouseLeave) self.Bind(wx.EVT_ENTER_WINDOW, self._onMouseEnter) self.Bind(wx.EVT_ERASE_BACKGROUND,self._onEraseBackground) self.Bind(wx.EVT_PAINT,self._onPaint) self._mouseIn = self._mouseDown = False def _onMouseEnter(self, event): self._mouseIn = True def _onMouseLeave(self, event): self._mouseIn = False def _onMouseDown(self, event): self._mouseDown = True def _onMouseUp(self, event): self._mouseDown = False self.sendButtonEvent() def sendButtonEvent(self): event = wx.CommandEvent(wx.wxEVT_COMMAND_BUTTON_CLICKED, self.GetId()) event.SetInt(0) event.SetEventObject(self) self.GetEventHandler().ProcessEvent(event) def _onEraseBackground(self,event): # reduce flicker pass def _onPaint(self, event): dc = wx.BufferedPaintDC(self) dc.SetFont(self.GetFont()) dc.SetBackground(wx.Brush(self.GetBackgroundColour())) dc.Clear() dc.DrawBitmap(self.Norm_bmp) # draw whatever you want to draw # draw glossy bitmaps e.g. dc.DrawBitmap if self._mouseIn: # If the Mouse is over the button dc.DrawBitmap(self, self.Mouse_over_bmp, self.Pos_bmp, useMask=False) if self._mouseDown: # If the Mouse clicks the button dc.DrawBitmap(self, self.Push_bmp, self.Pos_bmp, useMask=False)

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  • Is there any "modern" text editor with command-line/minibuffer?

    - by Pedro Morte Rolo
    A command line in a text editor is a wonderful feature. It allows the user to explore the editor's functionality and learn it's shortcuts in a textual way. It's much faster than using the mouse, and it is much easier to memorise "shortcuts" this way. Emacs and VI provide this, though, emacs and vi are not "modern". By "modern", I mean one that is original built to cope with the modern de-facto standards of selecting, copying, pasting, cutting, undoing, redoing and auto-completing. Cream/vi or Emacs/CUA are not valid options, since there are loads of things built over them that conflict with the mentioned stuff. It would be nice if there was an editor that would cope with the modern de-facto standards out-off-the-box, but still provide a command-line/minibuffer to perform/explore the commands and learn its shortcuts. Is there such a thing? I do not intend to use the "modern" term as derrogatory. I love both Emacs and VI, but I hate their keyboard-shortcut historical baggage. When I reffer to de-facto standards, I am not talking about Windows vs Whatever. Kate, gedit, Eclipse, Intelij or Textmate also follow the norm I am talking about and are not Windows editors. Please do not advertise Vim and Emacs, that's not answering the question. I am asking for alternatives. Why don't I like emacs and vi: Emacs: Despite CUA mode, emacs has loads of modes that conflict with this (e.g. slime, ruby-mode, etc...) It would be nice to have something that would work out-off-the-box. VI: I do not like that it is Visual/Insert-based. I do not know how to browse the text-editor's commands. I do not like that it is so much tought for the terminal. I believe that it has the same problem that I mentioned for emacs. This question is starting to look like requirement analysis.. As de-facto standards I mean: Ctrol-XCV for cut-copy-paste Ctrol-A for select-all Contrl-Z for Undo Ctrol-Y for Redo Control-F for Searching Contrl-Space for auto-complete Shift-arrow for selection Control-arrow for word-navigation Alt-Arrow for moving

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  • Reliable and fast way to convert a zillion ODT files in PDF?

    - by Marco Mariani
    I need to pre-produce a million or two PDF files from a simple template (a few pages and tables) with embedded fonts. Usually, I would stay low level in a case like this, and compose everything with a library like ReportLab, but I joined late in the project. Currently, I have a template.odt and use markers in the content.xml files to fill with data from a DB. I can smoothly create the ODT files, they always look rigth. For the ODT to PDF conversion, I'm using openoffice in server mode (and PyODConverter w/ named pipe), but it's not very reliable: in a batch of documents, there is eventually a point after which all the processed files are converted into garbage (wrong fonts and letters sprawled all over the page). Problem is not predictably reproducible (does not depend on the data), happens in OOo 2.3 and 3.2, in Ubuntu, XP, Server 2003 and Windows 7. My Heisenbug detector is ticking. I tried to reduce the size of batches and restarting OOo after each one; still, a small percentage of the documents are messed up. Of course I'll write about this on the Ooo mailing lists, but in the meanwhile, I have a delivery and lost too much time already. Where do I go? Completely avoid the ODT format and go for another template system. Suggestions? Anything that takes a few seconds to run is way too slow. OOo takes around a second and it sums to 15 days of processing time. I had to write a program for clustering the jobs over several clients. Keep the format but go for another tool/program for the conversion. Which one? There are many apps in the shareware or commercial repositories for windows, but trying each one is a daunting task. Some are too slow, some cannot be run in batch without buying it first, some cannot work from command line, etc. Open source tools tend not to reinvent the wheel and often depend on openoffice. Converting to an intermediate .DOC format could help to avoid the OOo bug, but it would double the processing time and complicate a task that is already too hairy. Try to produce the PDFs twice and compare them, discarding the whole batch if there's something wrong. Although the documents look equal, I know of no way to compare the binary content. Restart OOo after processing each document. it would take a lot more time to produce them it would lower the percentage of the wrong files, and make it very hard to identify them. Go for ReportLab and recreate the pages programmatically. This is the approach I'm going to try in a few minutes. Learn to properly format bulleted lists Thanks a lot.

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  • html horizontal scrolling

    - by mp
    Hi, i have a simple css example, and i can't understand the behavior of one of my divs, when the horizontal scroll is displayed. so...when my browser window needs to display the horizontal scroll(when the window width is less than my div "content" width(1024px)), my div "footer" (that have the same "content's" parent and 100% width), seems to get an "extra blank space" on the right side. this space grows when I reduce the width of the window. any ideas about how can i get it off, or why it happens??thanks! heres my code: css: <style type="text/css"> html, body { height: 100%; width:100%; font-family:"Arial Black", Gadget, sans-serif; font-size:11px; font-variant:normal; } * { margin: 0; } .wrapper { min-height: 100%; height: auto !important; height: 100%; margin: 0 auto -4em; } #content{ width:1024px; margin:0px auto; background-color:#990; height:780px; } .footer, .push { height: 4em; width:100%; } #footer-content{ height:10px; background-color:#09F; width:100%; } </style> html: <body> <div class="wrapper"> <div id="content"> <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nullam scelerisque varius tortor vitae pretium. Quisque magna ipsum, accumsan sit amet pretium sed, iaculis feugiat nibh. Donec vitae dui eros, eu ultricies nulla. Morbi aliquet, nisi in tincidunt rutrum, nisl justo sagittis nisi, nec dignissim orci elit vitae tortor. </p> </div> <div class="push"></div> </div> <div class="footer" style="background-color:#900; width:100%;"> <div id="footer-content"></div> </div> </body>

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  • Java map / nio / NFS issue causing a VM fault: "a fault occurred in a recent unsafe memory access op

    - by Matthew Bloch
    I have written a parser class for a particular binary format (nfdump if anyone is interested) which uses java.nio's MappedByteBuffer to read through files of a few GB each. The binary format is just a series of headers and mostly fixed-size binary records, which are fed out to the called by calling nextRecord(), which pushes on the state machine, returning null when it's done. It performs well. It works on a development machine. On my production host, it can run for a few minutes or hours, but always seems to throw "java.lang.InternalError: a fault occurred in a recent unsafe memory access operation in compiled Java code", fingering one of the Map.getInt, getShort methods, i.e. a read operation in the map. The uncontroversial (?) code that sets up the map is this: /** Set up the map from the given filename and position */ protected void open() throws IOException { // Set up buffer, is this all the flexibility we'll need? channel = new FileInputStream(file).getChannel(); MappedByteBuffer map1 = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size()); map1.load(); // we want the whole thing, plus seems to reduce frequency of crashes? map = map1; // assumes the host writing the files is little-endian (x86), ought to be configurable map.order(java.nio.ByteOrder.LITTLE_ENDIAN); map.position(position); } and then I use the various map.get* methods to read shorts, ints, longs and other sequences of bytes, before hitting the end of the file and closing the map. I've never seen the exception thrown on my development host. But the significant point of difference between my production host and development is that on the former, I am reading sequences of these files over NFS (probably 6-8TB eventually, still growing). On my dev machine, I have a smaller selection of these files locally (60GB), but when it blows up on the production host it's usually well before it gets to 60GB of data. Both machines are running java 1.6.0_20-b02, though the production host is running Debian/lenny, the dev host is Ubuntu/karmic. I'm not convinced that will make any difference. Both machines have 16GB RAM, and are running with the same java heap settings. I take the view that if there is a bug in my code, there is enough of a bug in the JVM not to throw me a proper exception! But I think it is just a particular JVM implementation bug due to interactions between NFS and mmap, possibly a recurrence of 6244515 which is officially fixed. I already tried adding in a "load" call to force the MappedByteBuffer to load its contents into RAM - this seemed to delay the error in the one test run I've done, but not prevent it. Or it could be coincidence that was the longest it had gone before crashing! If you've read this far and have done this kind of thing with java.nio before, what would your instinct be? Right now mine is to rewrite it without nio :)

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  • OpenGL suppresses exceptions in MFC dialog-based application

    - by Mikhail
    Hello. I have an MFC-driven dialog-based application created with MSVS2005. Here is my problem step by step. I have button on my dialog and corresponding click-handler with code like this: int* i = 0; *i = 3; I'm running debug version of program and when I click on the button, Visual Studio catches focus and alerts "Access violation writing location" exception, program cannot recover from the error and all I can do is to stop debugging. And this is the right behavior. Now I add some OpenGL initialization code in the OnInitDialog() method: HDC DC = GetDC(GetSafeHwnd()); static PIXELFORMATDESCRIPTOR pfd = { sizeof(PIXELFORMATDESCRIPTOR), // size of this pfd 1, // version number PFD_DRAW_TO_WINDOW | // support window PFD_SUPPORT_OPENGL | // support OpenGL PFD_DOUBLEBUFFER, // double buffered PFD_TYPE_RGBA, // RGBA type 24, // 24-bit color depth 0, 0, 0, 0, 0, 0, // color bits ignored 0, // no alpha buffer 0, // shift bit ignored 0, // no accumulation buffer 0, 0, 0, 0, // accum bits ignored 32, // 32-bit z-buffer 0, // no stencil buffer 0, // no auxiliary buffer PFD_MAIN_PLANE, // main layer 0, // reserved 0, 0, 0 // layer masks ignored }; int pixelformat = ChoosePixelFormat(DC, &pfd); SetPixelFormat(DC, pixelformat, &pfd); HGLRC hrc = wglCreateContext(DC); ASSERT(hrc != NULL); wglMakeCurrent(DC, hrc); Of course this is not exactly what I do, it is the simplified version of my code. Well now the strange things begin to happen: all initialization is fine, there are no errors in OnInitDialog(), but when I click the button... no exception is thrown. Nothing happens. At all. If I set a break-point at the *i = 3; and press F11 on it, the handler-function halts immediately and focus is returned to the application, which continue to work well. I can click button again and the same thing will happen. It seems like someone had handled occurred exception of access violation and silently returned execution into main application message-receiving cycle. If I comment the line wglMakeCurrent(DC, hrc);, all works fine as before, exception is thrown and Visual Studio catches it and shows window with error message and program must be terminated afterwards. I experience this problem under Windows 7 64-bit, NVIDIA GeForce 8800 with latest drivers (of 11.01.2010) available at website installed. My colleague has Windows Vista 32-bit and has no such problem - exception is thrown and application crashes in both cases. Well, hope good guys will help me :) PS The problem originally where posted under this topic.

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  • Recursive N-way merge/diff algorithm for directory trees?

    - by BobMcGee
    What algorithms or Java libraries are available to do N-way, recursive diff/merge of directories? I need to be able to generate a list of folder trees that have many identical files, and have subdirectories with many similar files. I want to be able to use 2-way merge operations to quickly remove as much redundancy as possible. Goals: Find pairs of directories that have many similar files between them. Generate short list of directory pairs that can be synchronized with 2-way merge to eliminate duplicates Should operate recursively (there may be nested duplicates of higher-level directories) Run time and storage should be O(n log n) in numbers of directories and files Should be able to use an embedded DB or page to disk for processing more files than fit in memory (100,000+). Optional: generate an ancestry and change-set between folders Optional: sort the merge operations by how many duplicates they can elliminate I know how to use hashes to find duplicate files in roughly O(n) space, but I'm at a loss for how to go from this to finding partially overlapping sets between folders and their children. EDIT: some clarification The tricky part is the difference between "exact same" contents (otherwise hashing file hashes would work) and "similar" (which will not). Basically, I want to feed this algorithm at a set of directories and have it return a set of 2-way merge operations I can perform in order to reduce duplicates as much as possible with as few conflicts possible. It's effectively constructing an ancestry tree showing which folders are derived from each other. The end goal is to let me incorporate a bunch of different folders into one common tree. For example, I may have a folder holding programming projects, and then copy some of its contents to another computer to work on it. Then I might back up and intermediate version to flash drive. Except I may have 8 or 10 different versions, with slightly different organizational structures or folder names. I need to be able to merge them one step at a time, so I can chose how to incorporate changes at each step of the way. This is actually more or less what I intend to do with my utility (bring together a bunch of scattered backups from different points in time). I figure if I can do it right I may as well release it as a small open source util. I think the same tricks might be useful for comparing XML trees though.

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  • Silverlight with MVVM Inheritance: ModelView and View matching the Model

    - by moonground.de
    Hello Stackoverflowers! :) Today I have a special question on Silverlight (4 RC) MVVM and inheritance concepts and looking for a best practice solution... I think that i understand the basic idea and concepts behind MVVM. My Model doesn't know anything about the ViewModel as the ViewModel itself doesn't know about the View. The ViewModel knows the Model and the Views know the ViewModels. Imagine the following basic (example) scenario (I'm trying to keep anything short and simple): My Model contains a ProductBase class with a few basic properties, a SimpleProduct : ProductBase adding a few more Properties and ExtendedProduct : ProductBase adding another properties. According to this Model I have several ViewModels, most essential SimpleProductViewModel : ViewModelBase and ExtendedProductViewModel : ViewModelBase. Last but not least, according Views SimpleProductView and ExtendedProductView. In future, I might add many product types (and matching Views + VMs). 1. How do i know which ViewModel to create when receiving a Model collection? After calling my data provider method, it will finally end up having a List<ProductBase>. It containts, for example, one SimpleProduct and two ExtendedProducts. How can I transform the results to an ObservableCollection<ViewModelBase> having the proper ViewModel types (one SimpleProductViewModel and two ExtendedProductViewModels) in it? I might check for Model type and construct the ViewModel accordingly, i.e. foreach(ProductBase currentProductBase in resultList) if (currentProductBase is SimpleProduct) viewModels.Add( new SimpleProductViewModel((SimpleProduct)currentProductBase)); else if (currentProductBase is ExtendedProduct) viewModels.Add( new ExtendedProductViewModels((ExtendedProduct)currentProductBase)); ... } ...but I consider this very bad practice as this code doesn't follow the object oriented design. The other way round, providing abstract Factory methods would reduce the code to: foreach(ProductBase currentProductBase in resultList) viewModels.Add(currentProductBase.CreateViewModel()) and would be perfectly extensible but since the Model doesn't know the ViewModels, that's not possible. I might bring interfaces into game here, but I haven't seen such approach proven yet. 2. How do i know which View to display when selecting a ViewModel? This is pretty the same problem, but on a higher level. Ended up finally having the desired ObservableCollection<ViewModelBase> collection would require the main view to choose a matching View for the ViewModel. In WPF, there is a DataTemplate concept which can supply a View upon a defined DataType. Unfortunately, this doesn't work in Silverlight and the only replacement I've found was the ResourceSelector of the SLExtensions toolkit which is buggy and not satisfying. Beside that, all problems from Question 1 apply as well. Do you have some hints or even a solution for the problems I describe, which you hopefully can understand from my explanation? Thank you in advance! Thomas

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