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  • JDBC call not executing

    - by dbyrne
    I am working on one of the DAOs for a medium sized web application. Unfortunately, it contains very convoluted logic, and makes hundreds of JDBC stored proc calls in loops. This is out of my control. I am working on a method inside the DAO which makes a single JDBC call. The simplified version of what this method looks like is this: DriverManager.registerDriver(new com.sybase.jdbc2.jdbc.SybDriver()); Connection con = DriverManager.getConnection((String)connectionDetails.get("DATABASE_URL") (String)connectionDetails.get("USERID"), (String)connectionDetails.get("PASSWORD")); String sqlToExecute = "{call " + STORED_PROC + "(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)}"; CallableStatement stmt = con.prepareCall(sqlToExecute); //Maybe I should try calling clearParameters here? stmt.setString(1,someData); //....Set of parameters.... if (!stmt.execute()) { //execute method never returns false } stmt.close(); Its pretty much a textbook JDBC call. All this stored proc does is insert a single row. Here is where things get crazy: This code works when you run it through a debugger line by line, but fails when you run it "full speed". Not only does it fail, but it doesn't throw any exception! The execute method always returns true. It just breezes right through the JDBC call without inserting a row to the database. If you go through the log files, copy the stored proc call and run it manually, it works (just like it does in debug mode). Whats strange is that the rest of the DAO, with all its hundreds of looped stored proc calls, works fine. My thinking is that Connection or CallableStatement is caching some value behind the scenes that is screwing things up. Has anyone ever seen anything like this before? A JDBC call failing with no exceptions? I know it will be impossible to provide a complete solution to this without seeing the whole application, I am just looking for suggestions on possible issues to investigate.

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  • Creating an appropriate index for a frequently used query in SQL Server

    - by Slauma
    In my application I have two queries which will be quite frequently used. The Where clauses of these queries are the following: WHERE FieldA = @P1 AND (FieldB = @P2 OR FieldC = @P2) and WHERE FieldA = @P1 AND FieldB = @P2 P1 and P2 are parameters entered in the UI or coming from external datasources. FieldA is an int and highly on-unique, means: only two, three, four different values in a table with say 20000 rows FieldB is a varchar(20) and is "almost" unique, there will be only very few rows where FieldB might have the same value FieldC is a varchar(15) and also highly distinct, but not as much as FieldB FieldA and FieldB together are unique (but do not form my primary key, which is a simple auto-incrementing identity column with a clustered index) I'm wondering now what's the best way to define an index to speed up specifically these two queries. Shall I define one index with... FieldB (or better FieldC here?) FieldC (or better FieldB here?) FieldA ... or better two indices: FieldB FieldA and FieldC FieldA Or are there even other and better options? What's the best way and why? Thank you for suggestions in advance!

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  • Will Learning C++ Help for Building Fast/No-Additional-Requirements Desktop Applications?

    - by vito
    Will learning C++ help me build native applications with good speed? Will it help me as a programmer, and what are the other benefits? The reason why I want to learn C++ is because I'm disappointed with the UI performances of applications built on top of JVM and .NET. They feel slow, and start slow too. Of course, a really bad programmer can create a slower and sluggish application using C++ too, but I'm not considering that case. One of my favorite Windows utility application is Launchy. And in the Readme.pdf file, the author of the program wrote this: 0.6 This is the first C++ release. As I became frustrated with C#’s large .NET framework requirements and users lack of desire to install it, I decided to switch back to the faster language. I totally agree with the author of Launchy about the .NET framework requirement or even a JRE requirement for desktop applications. Let alone the specific version of them. And some of the best and my favorite desktop applications don't need .NET or Java to run. They just run after installing. Are they mostly built using C++? Is C++ the only option for good and fast GUI based applications? And, I'm also very interested in hearing the other benefits of learning C++.

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  • Proper way to scan a range of IP addresses

    - by Josh G
    Given a range of IP addresses entered by a user (through various means), I want to identify which of these machines have software running that I can talk to. Here's the basic process: Ping these addresses to find available machines Connect to a known socket on the available machines Send a message to the successfully established sockets Compare the response to the expected response Steps 2-4 are straight forward for me. What is the best way to implement the first step in .NET? I'm looking at the System.Net.NetworkInformation.Ping class. Should I ping multiple addresses simultaneously to speed up the process? If I ping one address at a time with a long timeout it could take forever. But with a small timeout, I may miss some machines that are available. Sometimes pings appear to be failing even when I know that the address points to an active machine. Do I need to ping twice in the event of the request getting discarded? To top it all off, when I scan large collections of addresses with the network cable unplugged, Ping throws a NullReferenceException in FreeUnmanagedResources(). !? Any pointers on the best approach to scanning a range of IPs like this?

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  • wpf: capturing mouse does not work

    - by amethyste
    hello I am developing an kind of outlook calendar application where I need to make the appointment resizable from mouse. My first try with a thumb did not work properly so I tried another way. What I did is that: 1) on the botton of the appointmennt panel I added a rectangle to figure out the resize zone (the thumb). The appointment panel is put on a grid panel. 2) I intercept down event on the rectangle and send event to this code: private Point startPoint; private void OnResizeElementMouseDown(object sender, MouseButtonEventArgs e) { e.Handled = true; this.MouseMove += new MouseEventHandler(ResizeEndElement_MouseMove); this.MouseLeftButtonUp += new MouseButtonEventHandler(OnResizeElementMouseUp); // some code to perform new height computation Mouse.Capture(this); } where this is the appointment panel that own the thumb. Decreasing height works well. But increasing is more difficult. If I move the mouse very very slowly it's OK, if I speed it up a little bit it tends to leave out the appointment panel and then all MouseMove event are lost. I thought Mouse.Capture() was propose to solve this kind of problem, but in fact not. Does anybody know what is wrong in my code?

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  • How to display many SVGs in Java with high performance

    - by Oak
    What I want My goal is to be able to display a large number of SVG images on a single drawing area in Java, each with its own translation/rotation/scale values. I'm looking for the simplest solution allowing this, optionally even using OpenGL to speed things up. What I've Tried My initial naive approach was to use SVGSalamander to draw directly on a JPanel, but the performance was pathetic. I poked around around and learned that I should do something like manually convert each SVG into a BufferedImage created with createCompatibleImage, then do the transformations I want, then draw it using double buffering. I ran into some troubles here, and before I continued I tried looking for frameworks to simplify things. What I've Looked At I've been a bit overwhelmed by the available options, which is why I'm turning to SO for help. I've looked at: Cairo (with Glitz maybe?) Libart - not sure if this actually supports SVGs FengGUI Slick - looks promising but a bit of an overkill But couldn't decide what is best for me to start working with, and I hope someone here as experience with any of these doing similar things.

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  • Socket.Recieve Failing When Multithreaded

    - by Qua
    The following piece of code runs fine when parallelized to 4-5 threads, but starts to fail as the number of threads increase somewhere beyond 10 concurrentthreads int totalRecieved = 0; int recieved; StringBuilder contentSB = new StringBuilder(4000); while ((recieved = socket.Receive(buffer, SocketFlags.None)) > 0) { contentSB.Append(Encoding.ASCII.GetString(buffer, 0, recieved)); totalRecieved += recieved; } The Recieve method returns with zero bytes read, and if I continue calling the recieve method then I eventually get a 'An established connection was aborted by the software in your host machine'-exception. So I'm assuming that the host actually sent data and then closed the connection, but for some reason I never recieved it. I'm curious as to why this problem arises when there are a lot of threads. I'm thinking it must have something to do with the fact that each thread doesn't get as much execution time and therefore there are some idle time for the threads which causes this error. Just can't figure out why idle time would cause the socket not to recieve any data.

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  • Images not showing in ie7 using jquery cycle and jCarouselLite plugin

    - by Geetha
    Hi All, I am using jquery cycle and jCarouselLite plugin to display images as slide. Images are getting displayed in ie7. but working perfect in ie6. Image Property inside the cycle control: Protocol: Not available Type: Not available Address(url): Not available Size: Not available Dimensions: 100X100 but control having the url. if i tried that image url separate it showing the image. Code: $('#slide').cycle({ fx: 'fade', continuous: true, speed: 7500, timeout: 55000, sync: 1 }); Html Code: <div id="slide"> <img src="samp1.jpg" width="664" height="428" border="0" /> <img src="samp2.jpg" width="664" height="428" border="0" /> <img src="samp3.jpg" width="664" height="428" border="0" /> <img src="samp4.jpg" width="664" height="428" border="0" /> <img src="samp5.jpg" width="664" height="428" border="0" /> <img src="samp6.jpg" width="664" height="428" border="0" /> <img src="samp7.jpg" width="664" height="428" border="0" /> <img src="samp8.jpg" width="664" height="428" border="0" /> </div> Geetha.

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  • What is the best approach to 2D collision detection on the iPhone?

    - by Magic Bullet Dave
    Been working on this problem of collision detection and there appears to be 3 main approaches I could take: Sprite and mask approach. (AND the overlap of the sprites and check for a non-zero number in the resulting sprite pixel data). Bounding circles, rectangles or polygons. (Create one or more shapes that enclose the sprites and do the basic maths to check for overlaps). Use an existing sprite library. The first approach, even though it would have been the way I would have done it in the old days of 16x16 sprite blocks, it appears that there just isn’t an easy way of getting at the individual image pixel data and/or alpha channel within Quartz (or OPENGL for that matter). Detecting the overlap of the bounding box is easy, but then creating a 3rd image from the overlap and then testing it for pixels is complicated and my gut feel is that even if we could get it to work would be slow. Am I missing something neat here? The second approach involves dividing up our sprites into several polygons and testing them for overlaps. The more polygons the more accurate the collision detection. The benefit is that it is fast, and can be accurate. The downside is it makes the sprite creation more complicated. i.e., we have to create the polygons for each sprite. For speed the best approach is to create a tree of polygons. The 3rd approach I’m not sure about as it involves buying code (or using an open source licence). I am not sure what the best library to use is or whether this would make life easier or give us a problem integrating this into our app. So in short I am favouring the polygon and tree approach and would appreciate you views on this before I go and write lots of code. Best regards Dave

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  • SQL Server Long Query

    - by thormj
    Ok... I don't understand why this query is taking so long (MSSQL Server 2005): [Typical output 3K rows, 5.5 minute execution time] SELECT dbo.Point.PointDriverID, dbo.Point.AssetID, dbo.Point.PointID, dbo.Point.PointTypeID, dbo.Point.PointName, dbo.Point.ForeignID, dbo.Pointtype.TrendInterval, coalesce(dbo.Point.trendpts,5) AS TrendPts, LastTimeStamp = PointDTTM, LastValue=PointValue, Timezone FROM dbo.Point LEFT JOIN dbo.PointType ON dbo.PointType.PointTypeID = dbo.Point.PointTypeID LEFT JOIN dbo.PointData ON dbo.Point.PointID = dbo.PointData.PointID AND PointDTTM = (SELECT Max(PointDTTM) FROM dbo.PointData WHERE PointData.PointID = Point.PointID) LEFT JOIN dbo.SiteAsset ON dbo.SiteAsset.AssetID = dbo.Point.AssetID LEFT JOIN dbo.Site ON dbo.Site.SiteID = dbo.SiteAsset.SiteID WHERE onlinetrended =1 and WantTrend=1 PointData is the biggun, but I thought its definition should allow me to pick up what I want easily enough: CREATE TABLE [dbo].[PointData]( [PointID] [int] NOT NULL, [PointDTTM] [datetime] NOT NULL, [PointValue] [real] NULL, [DataQuality] [tinyint] NULL, CONSTRAINT [PK_PointData_1] PRIMARY KEY CLUSTERED ( [PointID] ASC, [PointDTTM] ASC ) WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO CREATE NONCLUSTERED INDEX [IX_PointDataDesc] ON [dbo].[PointData] ( [PointID] ASC, [PointDTTM] DESC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] GO PointData is 550M rows, and Point (source of PointID) is only 28K rows. I tried making an Indexed View, but I can't figure out how to get the Last Timestamp/Value out of it in a compatible way (no Max, no subquery, no CTE). This runs twice an hour, and after it runs I put more data into those 3K PointID's that I selected. I thought about creating LastTime/LastValue tables directly into Point, but that seems like the wrong approach. Am I missing something, or should I rebuild something? (I'm also the DBA, but I know very little about A'ing a DB!)

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  • jQuery weirdness. Div becomes attached to chained element markup?

    - by Scott B
    I've got a div in my app that is displayed each time my theme options panel is "saved". The markup is... <form method="post"> <?php if ( $_REQUEST['saved']) { ?> <div id="message" class="updated fade"><p>Sweet! The settings were saved :)</p></div> <script type="text/javascript"> $('#message').delay(3000).fadeOut(3000);</script> <?php }?> This has the effect of showing the div (which is absolutely positioned to overlay the interface). I'm also using jQuery to fade the message offscreen after 3 seconds. This works fine, however, when I add a bit of script to my jQuery chain (see the commented out block below), the message div is only visible when the jPicker popup appears. $(function() { $("#carousel").jCarouselLite ( { btnNext: ".next", btnPrev: ".prev", visible: 6, speed: 700 } ); $('#carousel').show(); $('#myTheme').change ( function() { var myImage = $('#myTheme :selected').text(); $('.selectedImage img').attr('src','../wp-content/themes/myTheme/styles/'+myImage+'/screenshot.jpg'); } ); $('#carousel ul li').click ( function(e) { var myOption = $(this).children('img').attr('title'); $("#myTheme option[value='"+myOption+"']").attr('selected', 'selected'); $("#myTheme").css('backgroundColor', '#A9A9A9').animate({backgroundColor: "#ffffff"}, 'slow'); } ); $('#carousel ul li').hover ( function(e) { var img_src = $(this).children('img').attr('src'); $('.selectedImage img').attr('src',img_src); } ,function() { $('.selectedImage img').attr('src', '<?php echo $selectedThumb; ?>'); } ); /* $('#myTheme_sidebar_color').jPicker ( {}, function(color) { $(this).val(color.get_Hex()); }, function(color) { $(this).val(color.get_Hex()); } ); */ });

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  • iPhone OpenGL ES Texture2D Masking

    - by Robert Neagu
    What's the best choice when trying to mask a texture like ColorSplash or other apps like iSteam, etc? I started learning OPENGL ES like... 4 days ago (I'm a total rookie) and tried the following approach: 1) I created a colored texture2D, a grayscale version of the first texture and a third texture2D called mask 2) I also created a texture2D for the brush... which is grayscale and it's opaque (brush = black = 0,0,0,1 and surroundings = white = 1,1,1,1). My intention was to create an antialiased brush with smooth edges but i'm fine with a normal one right now 3) I searched for masking techniques on the internet and found this tutorial ZeusCMD - Design and Development Tutorials : OpenGL ES Programming Tutorials - Masking about masking. The tutorial tells me to use blending to achieve masking... first draw colored, then mask with glBlendFunc(GL_DST_COLOR, GL_ZERO) and then grayscale with glBlendFunc(GL_ONE, GL_ONE) ... and this gives me something close to what i want... but not exactly what i want. The result is masked but it's somehow overbright-ed 4) For drawing to the mask texture i used an extra frame buffer object (FBO) I'm not really happy with the resulting image (overbright-ed picture) nor with the speed achieved with this method. I think the normal way was to draw directly to the grayscale (overlay) texture2D affecting only it's alpha channel in the places where the brush hits. Is there a fast way to achieve this? I have searched a lot and never got an answer that's clear and understandable. Then, in the main draw loop I could only draw the colored texture and then blend the grayscale ontop with glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA). I just want to learn to use OPENGL ES and it's driving me nuts because i can't get it to work properly. An advice, a link to a tutorial would be much appreciated.

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  • How to Resolve a Transformation Service with BRE that occurs after an Orchestration in an Itinerary?

    - by Maxime Labelle
    In trying to implement simple integration patterns with Biztalk ESB Toolkit 2.0, I'm facing a problem trying to resolve a Transformation Itinerary Service that occurs after an Orchestration. I'm using the BRE Resolver to execute rules that need to inspect the Context Message Type property to determine the appropriate map to use. However, once the message reaches the step in the Itinerary associated with the Transformation Service, the map fails to execute. From careful investigation, it appears that the message type is not supplied to the "Resolution" object that is used internally by the BRE resolver. Indeed, since the message leaving the preceding Orchestration is typed System.Xml.XmlDocument, the type of the message is "demoted" from the context. By tracking rules engine execution, I can observe that the type of the message is indeed lost when reaching the BRE resolver. The type of the message is empty, whereas the strongly-typed of the document is Microsoft.XLANGs.BaseTypes.Any. The Orchestration service that I use is taken straight from the samples that ship with ESB Toolkit 2.0. Is there a way to perform Context-Based BRE resolution after an Orchestration in an Itinerary?

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  • Efficient Clojure workflow?

    - by Alex B
    I am developing a pet project with Clojure, but wonder if I can speed up my workflow a bit. My current workflow (with Compojure) is: Start Swank with lein swank. Go to Emacs, connect with M-x slime-connect. Load all existing source files one by one. This also starts a Jetty server and an application. Write some code in REPL. When satisfied with experiments, write a full version of a construct I had in mind. Eval (C-c C-c) it. Switch REPL to namespace where this construct resides and test it. Switch to browser and reload browser tab with the affected page. Tweak the code, eval it, check in the browser. Repeat any of the above. There are a number of annoyances with it: I have to switch between Emacs and the browser (or browsers if I am testing things like templating with multiple browsers) all the time. Is there a common idiom to automate this? I used to have a JavaScript bit that reloads the page continuously, but it's of limited utility, obviously, when I have to interact with the page for more than a few seconds. My JVM instance becomes "dirty" when I experiment and write test functions. Basically namespaces become polluted, especially if I'm refactoring and moving the functions between namespaces. This can lead to symbol collisions and I need to restart Swank. Can I undef a symbol? I load all source files one by one (C-c C-k) upon restarting Swank. I suspect I'm doing it all wrong. Switching between the REPL and the file editor can be a bit irritating, especially when I have a lot of Emacs tabs open, alongside the browser(s). I'm looking for ways to improve the above points and the entire workflow in general, so I'd appreciate if you'd share yours. P. S. I have also used Vimclojure before, so Vimclojure-based workflows are welcome too.

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  • Is it safe to read regular expressions from a file?

    - by Zilk
    Assuming a Perl script that allows users to specify several text filter expressions in a config file, is there a safe way to let them enter regular expressions as well, without the possibility of unintended side effects or code execution? Without actually parsing the regexes and checking them for problematic constructs, that is. There won't be any substitution, only matching. As an aside, is there a way to test if the specified regex is valid before actually using it? I'd like to issue warnings if something like /foo (bar/ was entered. Thanks, Z. EDIT: Thanks for the very interesting answers. I've since found out that the following dangerous constructs will only be evaluated in regexes if the use re 'eval' pragma is used: (?{code}) (??{code}) ${code} @{code} The default is no re 'eval'; so unless I'm missing something, it should be safe to read regular expressions from a file, with the only check being the eval/catch posted by Axeman. At least I haven't been able to hide anything evil in them in my tests. Thanks again. Z.

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  • SQL Server service broker reporting as off when I have written a query to turn it on

    - by dotnetdev
    I have made a small ASP.NET website. It uses sqlcachedependency The SQL Server Service Broker for the current database is not enabled, and as a result query notifications are not supported. Please enable the Service Broker for this database if you wish to use notifications. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.InvalidOperationException: The SQL Server Service Broker for the current database is not enabled, and as a result query notifications are not supported. Please enable the Service Broker for this database if you wish to use notifications. Source Error: Line 12: System.Data.SqlClient.SqlDependency.Start(connString); This is the erroneous line in my global.asax. However, in sql server (2005), I enabled service broker like so (I connect and run the SQL Server service when I debug my site): ALTER DATABASE mynewdatabase SET ENABLE_BROKER with rollback immediate And this was successful. What am I missing? I am trying to use sql caching dependency and have followed all procedures. Thanks

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  • SSIS - Skip Missing Files

    - by Greg
    I have a SSIS 2008 package that calls about 10 other SSIS packages (legacy issues, don't ask). Each of those child packages loads a specific file into a table. But sometimes one or more of these input files will be missing. How can I let a child package fail (because a file is missing) but let the rest of the parent package keep on running? I've tried increasing the maximum error count on the parent package, the tasks in the parent package that call each child, and in the child package itself. None of that seemed to make any difference. I still get this error when I run it with a file missing: SSIS Warning Code DTS_W_MAXIMUMERRORCOUNTREACHED. The Execution method succeeded, but the number of errors raised (2) reached the maximum allowed (1); resulting in failure. This occurs when the number of errors reaches the number specified in MaximumErrorCount. Change the MaximumErrorCount or fix the errors. Edit: failpackageonfailure and faulparentonfailure are already all set to false everywhere.

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  • What is the fastest way to find duplicates in multiple BIG txt files?

    - by user2950750
    I am really in deep water here and I need a lifeline. I have 10 txt files. Each file has up to 100.000.000 lines of data. Each line is simply a number representing something else. Numbers go up to 9 digits. I need to (somehow) scan these 10 files and find the numbers that appear in all 10 files. And here comes the tricky part. I have to do it in less than 2 seconds. I am not a developer, so I need an explanation for dummies. I have done enough research to learn that hash tables and map reduce might be something that I can make use of. But can it really be used to make it this fast, or do I need more advanced solutions? I have also been thinking about cutting up the files into smaller files. To that 1 file with 100.000.000 lines is transformed into 100 files with 1.000.000 lines. But I do not know what is best: 10 files with 100 million lines or 1000 files with 1 million lines? When I try to open the 100 million line file, it takes forever. So I think, maybe, it is just too big to be used. But I don't know if you can write code that will scan it without opening. Speed is the most important factor in this, and I need to know if it can be done as fast as I need it, or if I have to store my data in another way, for example, in a database like mysql or something. Thank you in advance to anybody that can give some good feedback.

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  • Correct way to do timer function in Python

    - by bwawok
    Hi. I have a GUI application that needs to do something simple in the background (update a wx python progress bar, but that doesn't really matter). I see that there is a threading.timer class.. but there seems to be no way to make it repeat. So if I use the timer, I end up having to make a new thread on every single execution... like : import threading import time def DoTheDew(): print "I did it" t = threading.Timer(1, function=DoTheDew) t.daemon = True t.start() if __name__ == '__main__': t = threading.Timer(1, function=DoTheDew) t.daemon = True t.start() time.sleep(10) This seems like I am making a bunch of threads that do 1 silly thing and die.. why not write it as : import threading import time def DoTheDew(): while True: print "I did it" time.sleep(1) if __name__ == '__main__': t = threading.Thread(target=DoTheDew) t.daemon = True t.start() time.sleep(10) Am I missing some way to make a timer keep doing something? Either of these options seems silly... I am looking for a timer more like a java.util.Timer that can schedule the thread to happen every second... If there isn't a way in Python, which of my above methods is better and why?

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  • What is an efficient strategy for multiple threads posting jobs and waiting for response from a single thread?

    - by jakewins
    In java, what is an efficient solution to the following problem: I have multiple threads (10-20 or so) generating jobs ("Job Creators"), and a single thread capable of performing them ("The worker"). Once a job creator has posted a job, it should wait for the job to finish, yielding no result other than "it's done", before it keeps going. For sending the jobs to the worker thread, I think a ring buffer or similar standard fan-in setup would perhaps be a good approach? But for a Job Creator to find out that her job has been done, I'm not so sure.. The job creators could sleep, and the worker interrupt them when done.. Or each job creator could have an atomic boolean that it checks, and that the worker sets. I dunno, neither of those feel very nice. I'd like to do it with as few (none, if possible) locks as absolutely possible. So to be clear: What I'm looking for is speed, not necessarily simplicity. Does anyone have any suggestions? Links to reading about concurrency strategies would also be very welcome!

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  • How can I set a Java applet transparency to show contents behind it?

    - by yuri
    I've got a web page with an applet inside. This applet is a drop target on a drag and drop action from the OS, I simply take an image from a folder, drag it on the applet and something happens. I give this webpage to a graphic designer and he ask to if he can put an image behind the java applet so he can simulate to change the background using CSS (it is a skinned app and graphic design can change during execution). Practically i supposed to do: <div> <applet width="50" height="50" /> </div> with this CSS: div { width:50px; height:50px; background-image: url(image.jpg) center center no-repeat; } But it doesn't work (background is opaque). It is possible to set transparency to the applet without loosing drag and drop capabilities ? I'm searching something similar to flash wmode parameter. Better solutions implies only changes on the CSS/HTML without recompiling java class so the designing team can change the page structure without changing the Java.

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  • Php script running as scheduled task hangs - help!

    - by Ali
    Hi guys, I've built a php script that runs from the command line. It opens a connection into a pop3 email account and downloads all the emails and writes them to a database, and deletes them once downloaded. I have this script being called from the commandline by a bat file. in turn I have created a scheduled task which invokes the bat file every 5 minutes. The thing is that I have set the time out to zero for the fact that at times there could be emails with large attachments and the script actually downloads the attachments and stores them as raw files offline and the no timeout is so that the script doesnt die out during downloading. I've found that the program hangs sometimes and its a bit annoying at that - it always hangs are one point i.e. when negotiating the connection and getting connected to the mail server. And because the timeout is set to zero it seems to stay stuck up in taht position. And because of that the task is not run as its technically hung up. I want that the program should not timeout when downloading emails - however at the points where it is negotiating a connection or trying to connect to the mailserver there should be a timeout only at that point itself and not the rest of the program execution. How do I do this :(

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  • optimize 2D array in C++

    - by Hristo
    I'm dealing with a 2D array with the following characteristics: const int cols = 500; const int rows = 100; int arr[rows][cols]; I access array arr in the following manner to do some work: for(int k = 0; k < T; ++k) { // for each trainee myscore[k] = 0; for(int i = 0; i < N; ++i) { // for each sample for(int j = 0; j < E[i]; ++j) { // for each expert myscore[k] += delta(i, anotherArray[k][i], arr[j][i]); } } } So I am worried about the array 'arr' and not the other one. I need to make this more cache-friendly and also boost the speed. I was thinking perhaps transposing the array but I wasn't sure how to do that. My implementation turns out to only work for square matrices. How would I make it work for non-square matrices? Also, would mapping the 2D array into a 1D array boost the performance? If so, how would I do that? Finally, any other advice on how else I can optimize this... I've run out of ideas, but I know that arr[j][i] is the place where I need to make changes because I'm accessing columns by columns instead of rows by rows so that is not cache friendly at all. Thanks, Hristo

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  • Why does first call to java.io.File.createTempFile(String,String,File) take 5 seconds on Citrix?

    - by Ben Roling
    While debugging slow startup of an Eclipse RCP app on a Citrix server, I came to find out that java.io.createTempFile(String,String,File) is taking 5 seconds. It does this only on the first execution and only for certain user accounts. Specifically, I am noticing it Citrix anonymous user accounts. I have not tried many other types of accounts, but this behavior is not exhibited with an administrator account. Also, it does not matter if the user has access to write to the given directory or not. If the user does not have access, the call will take 5 seconds to fail. If they do have access, the call with take 5 seconds to succeed. This is on a Windows 2003 Server. I've tried Sun's 1.6.0_16 and 1.6.0_19 JREs and see the same behavior. I googled a bit expecting this to be some sort of known issue, but didn't find anything. It seems like someone else would have had to have run into this before. The Eclipse Platform uses File.createTempFile() to test various directories to see if they are writeable during initialization and this issue adds 5 seconds to the startup time of our application. I imagine somebody has run into this before and might have some insight. Here is sample code I executed to see that it is indeed this call that is consuming the time. I also tried it with a second call to createTempFile and notice that subsequent calls return nearly instantaneously. public static void main(final String[] args) throws IOException { final File directory = new File(args[0]); final long startTime = System.currentTimeMillis(); File file = null; try { file = File.createTempFile("prefix", "suffix", directory); System.out.println(file.getAbsolutePath()); } finally { System.out.println(System.currentTimeMillis() - startTime); if (file != null) { file.delete(); } } } Sample output of this program is the following: C:\java.exe -jar filetest.jar C:/Temp C:\Temp\prefix8098550723198856667suffix 5093

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  • How do I make this nested for loop, testing sums of cubes, more efficient?

    - by Brian J. Fink
    I'm trying to iterate through all the combinations of pairs of positive long integers in Java and testing the sum of their cubes to discover if it's a Fibonacci number. I'm currently doing this by using the value of the outer loop variable as the inner loop's upper limit, with the effect being that the outer loop runs a little slower each time. Initially it appeared to run very quickly--I was up to 10 digits within minutes. But now after 2 full days of continuous execution, I'm only somewhere in the middle range of 15 digits. At this rate it may end up taking a whole year just to finish running this program. The code for the program is below: import java.lang.*; import java.math.*; public class FindFib { public static void main(String args[]) { long uLimit=9223372036854775807L; //long maximum value BigDecimal PHI=new BigDecimal(1D+Math.sqrt(5D)/2D); //Golden Ratio for(long a=1;a<=uLimit;a++) //Outer Loop, 1 to maximum for(long b=1;b<=a;b++) //Inner Loop, 1 to current outer { //Cube the numbers and add BigDecimal c=BigDecimal.valueOf(a).pow(3).add(BigDecimal.valueOf(b).pow(3)); System.out.print(c+" "); //Output result //Upper and lower limits of interval for Mobius test: [c*PHI-1/c,c*PHI+1/c] BigDecimal d=c.multiply(PHI).subtract(BigDecimal.ONE.divide(c,BigDecimal.ROUND_HALF_UP)), e=c.multiply(PHI).add(BigDecimal.ONE.divide(c,BigDecimal.ROUND_HALF_UP)); //Mobius test: if integer in interval (floor values unequal) Fibonacci number! if (d.toBigInteger().compareTo(e.toBigInteger())!=0) System.out.println(); //Line feed else System.out.print("\r"); //Carriage return instead } //Display final message System.out.println("\rDone. "); } } Now the use of BigDecimal and BigInteger was delibrate; I need them to get the necessary precision. Is there anything other than my variable types that I could change to gain better efficiency?

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