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• Can a dropdown box using PHP / MySQL automatically select what was last saved in the database with it?

  - by wertz8090

  I am currently working on trying to get a dropdown box to display the most recently saved field each time I open a page for editing an item in an inventory. For example, let's say that my dropdown box selections are Iron, Copper, Gold, Silver, Titanium. The first time the dropdown box loads, I would like it to load in that order (the default order that I set it to). However, once a user submits a form that specifies a selection, I would like that selection to appear as the new default for the dropdown box (for example, if the user picks Gold, Gold will now display as the default). However - the new default that is selected and submitted can only appear for those fields which it is saved under (for example, since the user selected Gold, their preference is now saved as Gold and will appear as such under the field Necklace - however, Gold should not be the default for the fields Ring, Bracelet, and Earring when I open a page to view them). Basically, I need a dropdown box that can save the option of the latest selection on a page after the form is submitted, while at the same time making sure not to affect the default order of the dropdown box across other pages. Your help is much appreciated.

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• Web services or shared database for (game) server communication?

  - by jaaronfarr

  We have 2 server clusters: the first is made up of typical web applications backed by SQL databases. The second are highly optimized multiplayer game servers which keep all data in memory. Both clusters communicate with clients via HTTP (Ajax with JSON). There are a few cases in which we need to share data between the two server types, for example, reporting back and storing the results of a game (should ultimately end up in the database). We're considering several approaches for inter-server communication: Just share the MySQL databases between clusters (introduce SQL to the game servers) Sharing data in a distributed key-value store like Memcache, Redis, etc. Use an RPC technology like Google ProtoBufs or Apache Thrift Using RESTful web services (the game server would POST back to the web servers, for example) At the moment, we're leaning towards web services or just sharing the database. Sharing the database seems easy, but we're concerned this adds extra memory and a new dependency into the game servers. Web services provide good separation of concerns and fit with the existing Ajax we use, but add complexity, overhead and many more ways for communication to fail. Are there any other good reasons not to use one or the other approach? Which would be easier to scale?

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• Updating a C# 2.0 events example to be idiomatic with C# 3.5?

  - by Damien Wildfire

  I have a short events example from .NET 2.0 that I've been using as a reference point for a while. We're now upgrading to 3.5, though, and I'm not clear on the most idiomatic way to do things. How would this simple events example get updated to reflect idioms that are now available in .NET 3.5? // Args class. public class TickArgs : EventArgs { private DateTime TimeNow; public DateTime Time { set { TimeNow = value; } get { return this.TimeNow; } } } // Producer class that generates events. public class Metronome { public event TickHandler Tick; public delegate void TickHandler(Metronome m, TickArgs e); public void Start() { while (true) { System.Threading.Thread.Sleep(3000); if (Tick != null) { TickArgs t = new TickArgs(); t.Time = DateTime.Now; Tick(this, t); } } } } // Consumer class that listens for events. public class Listener { public void Subscribe(Metronome m) { m.Tick += new Metronome.TickHandler(HeardIt); } private void HeardIt(Metronome m, TickArgs e) { System.Console.WriteLine("HEARD IT AT {0}",e.Time); } } // Example. public class Test { static void Main() { Metronome m = new Metronome(); Listener l = new Listener(); l.Subscribe(m); m.Start(); } }

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• sql queries slower than expected

  - by neubert

  Before I show the query here are the relevant table definitions: CREATE TABLE phpbb_posts ( topic_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, poster_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, KEY topic_id (topic_id), KEY poster_id (poster_id), ); CREATE TABLE phpbb_topics ( topic_id mediumint(8) UNSIGNED NOT NULL auto_increment ); Here's the query I'm trying to do: SELECT p.topic_id, p.poster_id FROM phpbb_topics AS t LEFT JOIN phpbb_posts AS p ON p.topic_id = t.topic_id AND p.poster_id <> ... WHERE p.poster_id IS NULL; Basically, the query is an attempt to find all topics where the number of times someone other than the target user has posted in is zero. In other words, the topics where the only person who has posted is the target user. Problem is that query is taking a super long time. My general assumption when it comes to SQL is that JOINs of any are super fast and can be done in no time at all assuming all relevant columns are primary or foreign keys (which in this case they are). I tried out a few other queries: SELECT COUNT(1) FROM phpbb_topics AS t JOIN phpbb_posts AS p ON p.topic_id = t.topic_id; That returns 353340 pretty quickly. I then do these: SELECT COUNT(1) FROM phpbb_topics AS t JOIN phpbb_posts AS p ON p.topic_id = t.topic_id AND p.poster_id <> 77198; SELECT COUNT(1) FROM phpbb_topics AS t JOIN phpbb_posts AS p ON p.topic_id = t.topic_id WHERE p.poster_id <> 77198; And both of those take quite a while (between 15-30 seconds). If I change the < to a = it takes no time at all. Am I making some incorrect assumptions? Maybe my DB is just foobar'd?

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• Django + GAE (Google App Engine) : most convenient path for a beginner?

  - by mac

  Some background info first: Goal: a medium-level complexity web app that I will need to maintain and possibly extend for a few years. Experience: good knowledge of python, some experience of MVC frameworks (in PHP). Desiderata: using django and google app engine. I read extensively about the compatibility issues between GAE and Django, and I am aware of the GAE patch, the norel project, and other similar pieces of code. I have also understood that the SDK provides some of the features of django "out of the box". Yet, given that I have no previous experience with neither Django nor GAE, I am unable to evaluate to which extent using a patched version of Django will strip away important features, or how far the framework provided in the SDK is compatible with Django. So I am rather confused on what would be the best way to proceed in my situation: Should I simply use a patched version of Django as the differences with the original Django are so minor that I would hardly notice them? Should I write my app completely in "regular django" and try to port it to GAE only afterwards, when I will have got a grasp on Django internals and philosophy? Should I write my app using the framework provided with the SDK and port it to django only afterwards? Should I... ? Thank you in advance for your time and advice.

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• Algorithm to determine if array contains n...n+m?

  - by Kyle Cronin

  I saw this question on Reddit, and there were no positive solutions presented, and I thought it would be a perfect question to ask here. This was in a thread about interview questions: Write a method that takes an int array of size m, and returns (True/False) if the array consists of the numbers n...n+m-1, all numbers in that range and only numbers in that range. The array is not guaranteed to be sorted. (For instance, {2,3,4} would return true. {1,3,1} would return false, {1,2,4} would return false. The problem I had with this one is that my interviewer kept asking me to optimize (faster O(n), less memory, etc), to the point where he claimed you could do it in one pass of the array using a constant amount of memory. Never figured that one out. Along with your solutions please indicate if they assume that the array contains unique items. Also indicate if your solution assumes the sequence starts at 1. (I've modified the question slightly to allow cases where it goes 2, 3, 4...) edit: I am now of the opinion that there does not exist a linear in time and constant in space algorithm that handles duplicates. Can anyone verify this? The duplicate problem boils down to testing to see if the array contains duplicates in O(n) time, O(1) space. If this can be done you can simply test first and if there are no duplicates run the algorithms posted. So can you test for dupes in O(n) time O(1) space?

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• C++ and its type system: How to deal with data with multiple types?

  - by sub

  "Introduction" I'm relatively new to C++. I went through all the basic stuff and managed to build 2-3 simple interpreters for my programming languages. The first thing that gave and still gives me a headache: Implementing the type system of my language in C++ Think of that: Ruby, Python, PHP and Co. have a lot of built-in types which obviously are implemented in C. So what I first tried was to make it possible to give a value in my language three possible types: Int, String and Nil. I came up with this: enum ValueType { Int, String, Nil }; class Value { public: ValueType type; int intVal; string stringVal; }; Yeah, wow, I know. It was extremely slow to pass this class around as the string allocator had to be called all the time. Next time I've tried something similar to this: enum ValueType { Int, String, Nil }; extern string stringTable[255]; class Value { public: ValueType type; int index; }; I would store all strings in stringTable and write their position to index. If the type of Value was Int, I just stored the integer in index, it wouldn't make sense at all using an int index to access another int, or? Anyways, the above gave me a headache too. After some time, accessing the string from the table here, referencing it there and copying it over there grew over my head - I lost control. I had to put the interpreter draft down. Now: Okay, so C and C++ are statically typed. How do the main implementations of the languages mentioned above handle the different types in their programs (fixnums, bignums, nums, strings, arrays, resources,...)? What should I do to get maximum speed with many different available types? How do the solutions compare to my simplified versions above?

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• unicode convertion problem

  - by bhoomi-nature

  Hai frnds i am bhoomi new to php,i am having having below problem in my coding please can you help anyone 1.first i want to open one word document which is having content and i wann to edit it 2.for that i am opening word document from the server and at that time its opening with garbage value(i thing its not converting to utf8 format) 3.wen i delete that garbage value and insert something from textarea to that file it is going to insert and next time onwords its its getting open properly. 4.actually i wann that doc file should open with english words wats there in that doc instead of garbage value..first time opening only its giving problem. i am using below code for that please do the needful $filename = 'test.doc'; if(isset($_REQUEST['Submit'])){ $somecontent = stripslashes($_POST['somecontent']); // Let's make sure the file exists and is writable first. if (is_writable($filename)) { // In our example we're opening $filename in append mode. // The file pointer is at the bottom of the file hence // that's where $somecontent will go when we fwrite() it. if (!$handle = fopen($filename, 'w')) { echo "Cannot open file ($filename)"; exit; } // Write $somecontent to our opened file. if (fwrite($handle, $somecontent) === FALSE) { echo "Cannot write to file ($filename)"; exit; } echo "Success, wrote ($somecontent) to file ($filename) - Continue - "; fclose($handle); } else { echo "The file $filename is not writable"; } } else{ // get contents of a file into a string $handle = fopen($filename, 'r'); $somecontent = fread($handle, filesize($filename)); ? Edit file

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• Polling a web URL until event

  - by Jaxo

  I'm really sorry about the crappy title - if anybody has a better way of wording it, please edit it! I basically need to have a C# application run a function if the output of a URL is a certain value. For example, if the website says blue the background colour will be blue, red to make it red, etc. The problem is I don't want to spam my webserver with checks. The 4 bytes it downloads each time is negligible, but if I were to deploy this type of system on multiple computers, it would get slower and slower and the bandwidth would add up quickly. So my question is: How can my desktop application run a piece of code only when a web URL has a different output without checking each time? I can't use sockets, and any sort of LAN protocol won't end up working. My reasoning behind this potentially nefarious code is to be able to mute computers by updating a file on the website (as you may have seen in my previous question today, sorry!). I'd like it to be rather quick, and not have the refresh time minutes apart, a few seconds at the most would be ideal. How can I accomplish this? The website's code is easy, but getting the C# application to check when it changes is the part I'm stuck on. Nothing shows up on the website other than the command. Thanks!

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• Prolog, check if term is power of 2

  - by Riku

  i have written following code, which should work with my logic, but it does not. I should check if given term is power of two. For example s(s(s(nul))) should return false, s(s(s(s(nul))) should return true. substractWhileY(X,0,rezult). substractWhileY(s(X),Y,rezult):- Y > 0, number is 1, substractWhileY(X,Y - number, rezult). degreeOftwo(X):- substractWhileY(X,2,rezult), pagalba(X, 2, rezult). calculateAnswer(X, currentCounter, currentValue):- currentCounter is currentCounter * 2, substractWhileY(currentValue, currentCounter , rezult), rezult\= null, calculateAnswer(X, currentCounter , rezult). My idea was to check if given therm is degree of any two and if it is not than it is not the degree of two. With numbers it should work like this. For example i give number 8. First time it checks if 8 - 2 = 0. second time if 8 - 4 = 0. third time if 8 - 8 = 0. so the 8 id power of two. Maybe other solution would work better, so thanks for any help.

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• Dynamically assign class to paragraph

  - by user1684300

  How do you assign a class dynamically to a paragraph (via javascript/CSS) IF the paragraph contains the wording "Time Recorded:"? You'll notice that I have manually assigned the with class . However, I'd like to dynamically assign this class to any tag which contain the words "Time Recorded:". Please can you help ? Thank you. PLJ <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /> <title>Untitled Document</title> <link href="css.css" rel="stylesheet" type="text/css" /> </head> <body> <script type="text/javascript"> if (document.all || document.getElementById){ //if IE4 or NS6+ document.write('<style type="text/css">') document.write('.dyncontent{display:none;}') document.write('</style>') } </script> <div class="right"> <ul> <li class="say agent public"> <p>Description line 1</p> <p class="dyncontent">Time Recorded: 5MIN(S)</p> <p>Another description line</p> </li> </ul> </div> </body> </html>

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• Are workflows good for web service business logic?

  - by JL

  I have a series of complex web services that are getting used in my SOA application. I am generally happy with the overall design of the application, but as the complexity grows, I was wondering if Windows Workflow might be the way to go. My motivations for this are that you can get a graphic representation of the applications functionality, so it would be easier to maintain the code by its business function, rather than what I have now ( a standard 3 tier class library structure). My concerns are: I would be inducing an abstraction in my code, and I don't want to spend time having to deal with possible WF quirks or bugs. I've never worked with WF, is it a solid technology? I don't want to hit any WF limitations that prevent me from developing my solution. Is a WF even the right solution for the task? Simply put I am considering writing my next web service in this app to call a WF, and in this work flow manage the tasks the web service needs to carry out. I think it will be much neater and easier to maintain than a regular c# class library (maintainable by namespaces, classes ). Do you think this is the right thing to do? I'm hoping for positive feedback on WF (.net 4), but brutal honestly at the end of the day would help more. Thanks

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• PHP Fix Warning: Cannot modify header information - headers already sent...

  - by Storm Kiernan

  Warning: Cannot modify header information - headers already sent by (output started at /home/blocexco/public_html/homepage.php:73) in /home/blocexco/public_html/classes/mysql/mysql.security.php on line 99 This error is repeated a second time for mysql.security.php on line 100. homepage:73 <div class="login"> <?php require_once 'login.php'; ?> </div> mysql.security.php: 99-100 setcookie('username', "", time() - (60 * 60 * 24 * 365)); setcookie('password', "", time() - (60 * 60 * 24 * 365)); I know this isn't a "BOM" issue as I've read about. There is output before and after my calls to header() and setcookie() functions - this is necessary since the homepage includes a php file which then injects the right login or logout form. I've heard about using ob_start() at the beginning of content, but that's not a very specific instruction...I tried placing it at the beginning of homepage.php (just before the html tag) and that didn't fix anything. I'm new to PHP (a few days in, and new to web-app dev in general). To be honest, it blows my mind that I can't just change which page I am on, via php without bending over backwards...

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• [c++] accessing the hidden 'this' pointer

  - by Kyle

  I have a GUI architecture wherein elements fire events like so: guiManager->fireEvent(BUTTON_CLICKED, this); Every single event fired passes 'this' as the caller of the event. There is never a time I dont want to pass 'this', and further, no pointer except for 'this' should ever be passed. This brings me to a problem: How can I assert that fireEvent is never given a pointer other than 'this', and how can I simplify (and homogenize) calls to fireEvent to just: guiManager->fireEvent(BUTTON_CLICKED); At this point, I'm reminded of a fairly common compiler error when you write something like this: class A { public: void foo() {} }; class B { void oops() { const A* a = new A; a->foo(); } }; int main() { return 0; } Compiling this will give you ../src/sandbox.cpp: In member function ‘void B::oops()’: ../src/sandbox.cpp:7: error: passing ‘const A’ as ‘this’ argument of ‘void A::foo()’ discards qualifiers because member functions pass 'this' as a hidden parameter. "Aha!" I say. This (no pun intended) is exactly what I want. If I could somehow access the hidden 'this' pointer, it would solve both issues I mentioned earlier. The problem is, as far as I know you can't (can you?) and if you could, there would be outcries of "but it would break encapsulation!" Except I'm already passing 'this' every time, so what more could it break. So, is there a way to access the hidden 'this', and if not are there any idioms or alternative approaches that are more elegant than passing 'this' every time?

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• Setting the correct orientation for scrollbars in right-to-left pages.

  - by Daniel Lew

  I'm working with right-to-left layouts at the moment (think Hebrew or Arabic). In RTL, the page is generally flipped horizontally. However, I can't figure out how to change the orientation of the scrollbars. I would assume that the scrollbars should appear on the left side of a scrollable element, not the right side like it does in an LTR layout. Here is an example page where the scrollbar still appears on the right: <html dir="rtl"> <body> <div style="height: 100px; overflow: auto;"> <p>This is some text</p> <p>This is some text</p> <p>This is some text</p> <p>This is some text</p> <p>This is some text</p> </body> </html> Is the orientation of a scrollbar a browser locale setting, and thus is not something I should be concerned about, or is there a way to set the orientation of the scrollbar? (I'm not interested in implementing my own JavaScript scrollbar; if it turns out this is just a limitation of browsers then I'd rather live with that than add complexity to the page.)

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• Interview Q: sorting an almost sorted array (elements misplaced by no more than k)

  - by polygenelubricants

  I was asked this interview question recently: You're given an array that is almost sorted, in that each of the N elements may be misplaced by no more than k positions from the correct sorted order. Find a space-and-time efficient algorithm to sort the array. I have an O(N log k) solution as follows. Let's denote arr[0..n) to mean the elements of the array from index 0 (inclusive) to N (exclusive). Sort arr[0..2k) Now we know that arr[0..k) are in their final sorted positions... ...but arr[k..2k) may still be misplaced by k! Sort arr[k..3k) Now we know that arr[k..2k) are in their final sorted positions... ...but arr[2k..3k) may still be misplaced by k Sort arr[2k..4k) .... Until you sort arr[ik..N), then you're done! This final step may be cheaper than the other steps when you have less than 2k elements left In each step, you sort at most 2k elements in O(k log k), putting at least k elements in their final sorted positions at the end of each step. There are O(N/k) steps, so the overall complexity is O(N log k). My questions are: Is O(N log k) optimal? Can this be improved upon? Can you do this without (partially) re-sorting the same elements?

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• Which of these methods provides for the fastest page loading?

  - by chromedude

  I am building a database in MySQL that will be accessed by PHP scripts. I have a table that is the activity stream. This includes everything that goes on on the website (following of many different things, liking, upvoting etc.). From this activity stream I am going to run an algorithm for each user depending on their activity and display relevant activity. Should I create another table that stores the activity for each user once the algorithm has been run on the activity or should I run the algorithm on the activity table every time the user accesses the site? UPDATE:(this is what is above except rephrased hopefully in an easier to understand way) I have a database table called activity. This table creates a new row every time an action is performed by a user on the website. Every time a user logs in I am going to run an algorithm on the new rows (since the users last login) in the table (activity) that apply to them. For example if the user is following a user who upvoted a post in the activity stream that post will be displayed when the user logs in. I want the ability for the user to be able to access previous content applying to them. Would it be easiest to create another table that saved the rows that have already been run over with the algorithm except attached to individual users names? (a row can apply to multiple different users)

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• Can a second stored procedure doing the same thing finish before first one?

  - by evanmortland

  Hello, I have an audit record table that I am writing to. I am connecting to MyDb, which has a stored procedure called 'CreateAudit', which is a passthrough stored procedure to another database on the same machine called 'CreatedAudit' as well. I call the CreateAudit stored procedure from my application, using subsonic as the DAL. The first time I call it, I call it with the following (pseudocode): Result = CreateAudit(recordId, "Opened") Right after that, I call: Result2 = CreateAudit(recordId, "Closed") In my second stored procedure it is supposed to mark the record that was created by the CreateAudit(recordId, "Opened") with a status of closed. It works great if I run them independently of one another, but when they run in sequence in the application, the record is not marked as "Closed". When I run SQL profiler I see that both queries ran, and if I copy the queries out and run them from query analyzer the record gets marked as closed 100% of the time! When I run it from the application, about once every 20 times or so, the record is successfully marked closed - the other 19 times nothing happens, but I do not get an error! Is it possible for the .NET app to skip over the ouput from the first stored procedure and start executing the second stored procedure before the record in the first is created? When I add a "WAITFOR DELAY '00:00:00:003'" to the top of my stored procedure, the record is also closed 100% of the time. My head is spinning, any ideas why this is happening! Thanks for any responses, very interested in hearing how this can happen.

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• How do I determine when two moving points become visible to each other?

  - by Devin Jeanpierre

  Suppose I have two points, Point1 and Point2. At any given time, these points may be at different positions-- they are not necessarily static. Point1 is located at some position at time t, and its position is defined by the continuous functions x1(t) and y1(t) giving the x and y coordinates at time t. These functions are not differentiable, they are constructed piecewise from line segments. Point2 is the same, with x2(t) and y2(t), each function having the same properties. The obstacles that might prevent visibility are simple (and immobile) polygons. How can I find the boundary points for visibility? i.e. there are two kinds of boundaries: where the points become visible, and become invisible. For a become-visible boundary i, there exists some ?0, such that for any real number a, a ? (i-?, i) , Point1 and Point2 are not visible (i.e. the line segment that connects (x1(a), y1(a)) to (x2(a), y2(x)) crosses some obstacles). For b ? (i, i+?) they are visible. And it is the other way around for becomes-invisible. But can I find such a precise boundary, and if so, how?

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• What is common between environments within a shell terminal session?

  - by Matt1776

  I have a custom shell script that runs each time a user logs in or identity is assumed, its been placed in /etc/profile.d and performs some basic env variable operations. Recently I added some code so that if screen is running it will reattach it without needing me to type anything. There are some problems however. If I log-in as root, and su - to another user, the code runs a second time. Is there a variable I can set when the code runs the first time that will prevent a second run of the code? I thought to write something to the disk but then I dont want to prevent the code from running if I begin a new terminal session. Here is the code in question. It first attempts to reattach - if unsuccessful because its already attached (as it might be on an interruped session) it will 'take' the session back. screen -r if [ -z "$STY" ]; then exec screen -dR fi Ultimately this bug prevents me from substituting user to another user because as soon as I do so, it grabs the screen session and puts me right back where I started. Pretty frustrating

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• Project management software, available options

  - by canni

  Hey, sorry for posting this here, I know that this question better suites into SuperUser, but I would like to know answers from developers point of view. I have been using Indefero for project management etc. for some time, but I found that Indefero limitations are too big for my team. I'm searching project-management software that best suites this needs: Open-Source, but I can consider commercial apps GIT integration is mandatory, best if it can support multiple repos per project Time-tracking, good if it can have Gannt chart connected with issues etc. Issue, milestone, task tracking Good if it can be integrated with Gitosis, or have similar repository access control It must have an option, to setup on our own server Markdown syntax support is mandatory (or easy way to install plugin for this etc.) Issue tagging will be and advantage It will be used by developers team by 99% of time, but it has to have some simple interface, that clients can fill up bug reports etc. per project. It does not have to fill all this needs, but good if it can :) What options do You know, and can recommend?

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• Ant Junit tests are running much slower via ant than via IDE - what to look at?

  - by Alex B

  I am running my junit tests via ant and they are running substantially slower than via the IDE. My ant call is: <junit fork="yes" forkmode="once" printsummary="off"> <classpath refid="test.classpath"/> <formatter type="brief" usefile="false"/> <batchtest todir="${test.results.dir}/xml"> <formatter type="xml"/> <fileset dir="src" includes="**/*Test.java" /> </batchtest> </junit> The same test that runs in near instantaneously in my IDE (0.067s) takes 4.632s when run through Ant. In the past, I've been able to speed up test problems like this by using the junit fork parameter but this doesn't seem to be helping in this case. What properties or parameters can I look at to speed up these tests? More info: I am using the reported time from the IDE vs. the time that the junit task outputs. This is not the sum total time reported at the end of the ant run. So, bizarrely, this problem has resolved itself. What could have caused this problem? The system runs on a local disk so that is not the problem.

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• Using multiple Qt (SQL) Models

  - by radix07

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

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• How to construct objects based on XML code?

  - by the_drow

  I have XML files that are representation of a portion of HTML code. Those XML files also have widget declarations. Example XML file: <message id="msg"> <p> <Widget name="foo" type="SomeComplexWidget" attribute="value"> inner text here, sets another attribute or inserts another widget to the tree if needed... </Widget> </p> </message> I have a main Widget class that all of my widgets inherit from. The question is how would I create it? Here are my options: Create a compile time tool that will parse the XML file and create the necessary code to bind the widgets to the needed objects. Advantages: No extra run-time overhead induced to the system. It's easy to bind setters. Disadvantages: Adds another step to the build chain. Hard to maintain as every widget in the system should be added to the parser. Use of macros to bind the widgets. Complex code Find a method to register all widgets into a factory automatically. Advantages: All of the binding is done completely automatically. Easier to maintain then option 1 as every new widget will only need to call a WidgetFactory method that registers it. Disadvantages: No idea how to bind setters without introducing a maintainability nightmare. Adds memory and run-time overhead. Complex code What do you think is better? Can you guys suggest a better solution?

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• when to use Hibernate vs. Simple ResultSets for small application

  - by luke

  I just started working on upgrading a small component in a distributed java application. The main application is a rather complicated applet/servlet combo running on JBoss and it extensively uses Hibernate for its DataAccess. The component i am working on however is very a very straightforward data importing service. Basically the workflow is Listen for a network event Parse the data packet, extract a set of identifiers Map the identifier set to a primary key in our database Parse the rest of the packet and insert items in a related table using the foreign key found in step 3 Repeat in the previous version of this component it used a hibernate based DAL, that is no longer usable for a variety of reasons (in particular it is EOL), so I am in charge of replacing the Data Access layer for this component. So on the one hand I think i should use Hibernate because that's what the rest of the application does, but on the other i think i should just use regular java.sql.* classes because my requirements are really straightforward and aren't expected to change any time soon. So my question is (and i understand it is subjective) at what point do you think that the added complexity of using an ORM tool (in terms of configuration, dependencies...) is worth it? UPDATE due to the way the DataAccesLayer for the main application was written (weird dependencies) i cannot easily use it, i would have to implement it myself.

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