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  • Any utility to test expand C/C++ #define macros?

    - by Randy
    It seems I often spend way too much time trying to get a #define macro to do exactly what i want. I'll post my current delemia below and any help is appreciated. But really the bigger question is whether there is any utility someone could reccomend, to quickly display what a macro is actually doing? It seems like even the slow trial and error process would go much faster if I could see what is wrong. Currently, I'm dynamically loading a long list of functions from a DLL I made. The way I've set things up, the function pointers have the same nanes as the exported functions, and the typedef(s) used to prototyp them have the same names, but with a prepended underscor. So I want to use a define to simplfy assignments of a long long list of function pointers. For example, In the code statement below, 'hexdump' is the name of a typdef'd function point, and is also the name of the function, while _hexdump is the name of the typedef. If GetProcAddress() fails, a failure counter in incremented. if (!(hexdump = (_hexdump)GetProcAddress(h, "hexdump"))) --iFail; So lets say I'd like to rplace each line like the above with a macro, like this... GETADDR_FOR(hexdump ) Well this is the best I've come up with so far. It doesn't work (my // comment is just to prevent text formatting in the message)... // #define GETADDR_FOR(a) if (!(a = (#_#a)GetProcAddress(h, "/""#a"/""))) --iFail; And again, while I'd APPRECIATE an insight into what silly mistake I've made, it would make my day to have a utility that would show me the error of my ways, by simply plugging in my macro

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  • C++ NetUserAdd() not working?

    - by Brett Powell
    I posted earlier about how to do this, and got some great replies, and have managed to get the code written based off the MSDN example. However, it does not seem to be working properly. Its printing out the ERROR_ACCESS_DENIED message, but im not sure why as I am running it as a full admin. I was initially trying to create a USER_PRIV_ADMIN, but the MSDN said it can only use USER_PRIV_USER, but sadly neither work. Im hoping someone can spot a mistake or has an idea. Thanks! void AddRDPUser() { USER_INFO_1 ui; DWORD dwLevel = 1; DWORD dwError = 0; NET_API_STATUS nStatus; ui.usri1_name = L"DummyUserAccount"; ui.usri1_password = L"a2cDz3rQpG8"; //ignored by NetUserAdd //ui.usri1_password_age = -1; ui.usri1_priv = USER_PRIV_USER; //USER_PRIV_ADMIN; ui.usri1_home_dir = NULL; ui.usri1_comment = NULL; ui.usri1_flags = UF_SCRIPT; ui.usri1_script_path = NULL; nStatus = NetUserAdd(NULL, dwLevel, (LPBYTE)&ui, &dwError); switch (nStatus) { case NERR_Success: { Msg("SUCCESS!\n"); break; } case NERR_InvalidComputer: { fprintf(stderr, "A system error has occurred: NERR_InvalidComputer\n"); break; } case NERR_NotPrimary: { fprintf(stderr, "A system error has occurred: NERR_NotPrimary\n"); break; } case NERR_GroupExists: { fprintf(stderr, "A system error has occurred: NERR_GroupExists\n"); break; } case NERR_UserExists: { fprintf(stderr, "A system error has occurred: NERR_UserExists\n"); break; } case NERR_PasswordTooShort: { fprintf(stderr, "A system error has occurred: NERR_PasswordTooShort\n"); break; } case ERROR_ACCESS_DENIED: { fprintf(stderr, "A system error has occurred: ERROR_ACCESS_DENIED\n"); break; } } }

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  • Why it's important to specify the complete class name in your association when using namespaces

    - by Carmine Paolino
    In my Rails application there is a model that has some has_one associations (this is a fabricated example): class Person::Admin < ActiveRecord::Base has_one :person_monthly_revenue has_one :dude_monthly_niceness accepts_nested_attributes_for :person_monthly_revenue, :dude_monthly_niceness end class Person::MonthlyRevenue < ActiveRecord::Base belongs_to :person_admin end class Dude::MonthlyNiceness < ActiveRecord::Base belongs_to :person_admin end The application talks to a backend that computes some data and returns a piece of JSON like this: { "dude_monthly_niceness": { "february": 1.1153232569518972, "october": 1.1250217200558268, "march": 1.3965786869658541, "august": 1.6293418014601631, "september": 1.4062771500697835, "may": 1.7166279693955291, "january": 1.0086401628086725, "june": 1.5711510228365859, "april": 1.5614525597326563, "december": 0.99894169970474289, "july": 1.7263264324994585, "november": 0.95044938418509506 }, "person_monthly_revenue": { "february": 10.585596551505297, "october": 10.574823016656749, "march": 9.9125274764852787, "august": 9.2111604702328922, "september": 9.7905249446675153, "may": 9.1329712474607962, "january": 10.479614016604238, "june": 9.3710235926961936, "april": 9.5897372624830304, "december": 10.052587677671438, "july": 8.9508877843925561, "november": 10.925339756096172 }, } To deserialize it, I use ActiveRecord's from_json, but instead of a Person::Admin object with all the associations in place, I get this error: >> Person::Admin.new.from_json(json) NameError: uninitialized constant Person::Admin::DudeMonthlyNiceness Am I doing something wrong? Is there a better way to deserialize data? (I can modify the backend easily) UPDATE: the original title was "How to deserialize from json to ActiveRecord objects with associations?" but it ended up being my mistake in specifying associations so I changed the title.

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  • How do C++ compilers actually pass reference parameters?

    - by T.E.D.
    This question came about as a result of some mixed-langauge programming. I had a Fortran routine I wanted to call from C++ code. Fortran passes all its parameters by reference (unless you tell it otherwise). So I thought I'd be clever (bad start right there) in my C++ code and define the Fortran routine something like this: extern "C" void FORTRAN_ROUTINE (unsigned & flag); This code worked for a while but (of course right when I needed to leave) suddenly started blowing up on a return call. Clear indication of a munged call stack. Another engineer came behind me and fixed the problem, declaring that the routine had to be deinfed in C++ as extern "C" void FORTRAN_ROUTINE (unsigned * flag); I'd accept that except for two things. One is that it seems rather counter-intuitive for the compiler to not pass reference parameters by reference, and I can find no documentation anywhere that says that. The other is that he changed a whole raft of other code in there at the same time, so it theoretically could have been another change that fixed whatever the issue was. So the question is, how does C++ actually pass reference parameters? Is it perhaps free to do copy-in, copy-out for small values or something? In other words, are reference parameters utterly useless in mixed-language programming? I'd like to know so I don't make this same code-killing mistake ever again.

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  • c++ specialized overload?

    - by acidzombie24
    -edit- i am trying to close the question. i solved the problem with boost::is_base_and_derived In my class i want to do two things. 1) Copy int, floats and other normal values 2) Copy structs that supply a special copy function (template T copyAs(); } the struct MUST NOT return int's unless i explicitly say ints. I do not want the programmer mistaking the mistake by doing int a = thatClass; -edit- someone mention classes dont return anything, i mean using the operator Type() overload. How do i create my copy operator in such a way i can copy both 1) ints, floats etc and the the struct restricted in the way i mention in 2). i tried doing template <class T2> T operator = (const T2& v); which would cover my ints, floats etc. But how would it differentiate from structs? so i wrote T operator = (const SomeGenericBase& v); The idea was the GenericBase would be unsed instead then i can do v.Whatever. But that backfires bc the functions i want wouldnt exist, unless i use virtual, but virtual templates dont exist. Also i would hate to use virtual I think the solution is to get rid of ints and have it convert to something that can do .as(). So i wrote something up but now i have the same problem, how does that differentiate ints and structs that have the .as() function template?

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  • There is a Default instance of form in VB.Net but not in C#, WHY?

    - by Shekhar_Pro
    I'm just curious to know that there is The (Name) property, which represents the name of the Form class.This property is used within the namespace to uniquely identify the class that the Form is an instance of and, in the case of Visual Basic, is used to access the default instance of the form. Now where this Default Instance come from, why can't C# have a equivalent method to this. Also for example to show a form in C# we do something like this: //Only method Form1 frm = new Form1(); frm.Show(); But in VB.Net we have both ways to do it: //'First common method (used slash because editor wouldn't format it properly) Form1.Show(); //'Second method Dim frm as New Form1(); frm.Show(); My question comes from this first method. What is this Form1, is it an instance of Form1 or the Form1 class itself. Now as i mentioned above the Form name is the Default instance in VB.Net. But we also know that Form1 is a class defined in Designer so how can the names be same for both the Instance and class name. If Form1 is Class then there is no (Static\Shared) method named Show(). So where does this method come from. And finally why C# can't have an equivalent of this. If there some mistake in my question Please let me know *I've checked this on stackoverflow, but couldn't find an answer to this.If you do find then please give a link to it.*

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  • some problem with iOS 4.2.1

    - by bicbac
    Hi, I've been developing an app with MacBook Pro (MBP) so far. Last week one of my friends gave me new macbook air 11"(MBA). so Now I can test my code with more than one machine with the same version of developing tools - Both machine has Xcode (3.2.5) and iOS SDK 4.2.1). After some point my app starts get terminated suddenly(iPhone sumulator), and I was using MBP. I got no error message whatsoever. it just stops. I reckon the crash comes from dealing with memory, like 'release'/ 'double-release'. (I'm not 100% sure though). Anyway I thought there must be some mistake within my code for sure. -Confusion starts from this part.- With my MBA, on the other hand, I don'y see any crash. It just works fine. There is nothing different between MBA & MBP except the h/w specifications. Same code, same versions of XCode and iOS SDK. Is the fact that no crash at MBA suggesting that I have to look somewhere else than the code itself? I red some article and Q&As on iOS4.2.1 and XCode 3.2.5 that the most recent version of XCode doesn't recognize the iOS 4.2.1 since the 4.2.1 came out later the 3.2.5. Is it the reason? I have no idea at this moment what should be the next move. thanks

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  • How to prevent the user from leaving the page

    - by JohnathanKong
    Hey Everyone, I am currently building a registration site where if the user leaves, I want to pop up a CSS box asking him if he is sure or not. I can accomplish this feat using confirm boxes, but the client says that they are too ugly. I've tried using unload and beforeunload, but both cannot stop the page from being redirected. Using those to events, I return false, so maybe there's a way to cancel other than returning false? Another solution that I've had was redirecting them to another page that has my popup, but the problem with that is that if they do want to leave the page, and it wasn't a mistake, they lose the page they were originally trying to go to. If I was a user, that would irritate me. The last solution was real popup window. The only thing I don't like about that is that the main winow will have their destination page while the pop will have my page. In my opinion it looks disjoint. On top of that, I'd be worried about popup blockers.

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  • MediaWiki: how to hide users from the user list?

    - by Dave Everitt
    I've set up Mediawiki 1.15.1 for a client who has added two users by mistake. They now want to hide these users from the user list. It seems this is done via the $wgGroupPermissions array with $wgGroupPermissions['suppress']['hideuser'] = true;, but it isn't at all clear what entry this needs for the hiding to work, or whether a new group ('hidden' or whatever) has to be created first with $wgAddGroups['bureaucrat'] = true;. For now, I've added the two users to be hidden to the 'Oversight' group which explains 'Block a username, hiding it from the public (hideuser)', but they still appear on the Special:ListUsers page. At a loss as to how the MediWiki arrays alter options displayed in the interface, so far I've added this to LocalSettings.php: $wgGroupPermissions['suppress']['hideuser'] = true; $wgAddGroups['supress'] = true; Or - since they haven't actually added anything to the wiki - could they simply be removed from the MySQL users table - although MediaWiki warns against this? Has anyone else done this successfully? Update - this is a hole in MediaWiki admin (although there are workarounds). See this thread on MediaWIki Users and the note to the reply below.

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  • Internal Java code best practice for dealing with invalid REST API parameters

    - by user326389
    My colleague wrote the following stackoverflow question: other stack overflow question on this topic The question seems to have been misinterpreted and I want to find out the answer, so I'm starting this new question... hopefully a little more clear. Basically, we have a REST API. Users of our API call our methods with parameters. But sometimes users call them with the wrong parameters!! Maybe a mistake in their code, maybe they're just trying to play with us, maybe they're trying to see how we respond, who knows! We respond with HTTP status error codes and maybe a detailed description of the invalid parameter in the XML response. All is well. But internally we deal with these invalid parameters by throwing exceptions. For example, if someone looks up a Person object by giving us their profile id, but the profile id doesn't exist... we throw a PersonInvalidException when looking them up. Then we catch this exception in our API controller and send back an HTTP 400 status error code. Our question is... is this the best practice, throwing exceptions internally for this kind of user error? These exceptions never get propogated back to the user, this is a REST API. They only make our code cleaner. Otherwise we could have a validation method in each of our API controllers to make sure the parameters all make sense, but that seems inefficient. We have to look up things in our database potentially twice. Or we could return nulls and check for them, but that sucks... What are your thoughts?

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  • FDs not closed in FUSE filesystem

    - by cor
    Hi, I have a problem while implementing a fuse filesystem in python. for now i just have a proxy filesystem, exactly like a mount --bind would be. But, any file created, opened, or read on my filesystem is not released (the corresponding FD is not closed) Here is an example : yume% ./ProxyFs.py `pwd`/test yume% cd test yume% ls mdr yume% echo test test yume% ls mdr test yume% ps auxwww | grep python cor 22822 0.0 0.0 43596 4696 ? Ssl 12:57 0:00 python ./ProxyFs.py /home/cor/esl/proxyfs/test cor 22873 0.0 0.0 6352 812 pts/1 S+ 12:58 0:00 grep python yume% ls -l /proc/22822/fd total 0 lrwx------ 1 cor cor 64 2010-05-27 12:58 0 - /dev/null lrwx------ 1 cor cor 64 2010-05-27 12:58 1 - /dev/null lrwx------ 1 cor cor 64 2010-05-27 12:58 2 - /dev/null lrwx------ 1 cor cor 64 2010-05-27 12:58 3 - /dev/fuse l-wx------ 1 cor cor 64 2010-05-27 12:58 4 - /home/cor/test/test yume% Does anyone have a solution to actually really close the fds of the file I use in my fs ? I'm pretty sure it's a mistake in the implementation of the open, read, write hooks but i'm stucked... Let me know if you need more details ! Thanks a lot Cor

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  • subscript requires array or pointer ERROR

    - by Kristian
    Hi, I know what is my mistake can't figer how to solve it. Im writing an winAPI that counts how many 'a' characters are found is a givien file. Im still getting the error " subscript requires array or pointer " (please find the comment in the code) #include "stdafx.h" #include <windows.h> int _tmain(int argc, _TCHAR* argv[]) { WCHAR str=L'a'; HANDLE A; TCHAR *fn; fn=L"d:\\test.txt"; A= CreateFile(fn,GENERIC_READ,0,NULL,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,NULL); if(A==INVALID_HANDLE_VALUE) { _tprintf(L"cannot open file \n"); } else { DWORD really; int countletter; int stringsize; do { BYTE x[1024]; ReadFile(A,x,1024,&really,NULL); stringsize = sizeof(really); for(int i =0;i<stringsize;i++) { if(really[i]==str) //here Im getting the error countletter++; } }while(really==1024); CloseHandle(A); _tprintf(L"NUmbers of A's found is %d \n",countletter); } return 0; } now I know I can't make comparesion between array and a WCHAR but hw to fix it ?

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  • Node.js/Express Partials problem: Can't be nested too deep?

    - by heorling
    I'm learning Node.js, Express, haml.js and liking it. I've run into a prety annoying problem though. I'm pretty new to this but have been getting nice results so far. I'm writing a jquery heavy web app that relies on a table containing divs. The divs slide around, switch back and fourth and are resized etc to my hearts content. What I'm looking for a way to switch (template?) the divs. Since I've been building in express and mimicking the chat example it would make sense to use partials. The rub is that I've been using inexplicit divs in haml, held within a td. The divs are cunstructed as follows: %tr %td .class1.class2.class3.classetc Which has worked fine cross browser. Parsing the classes works great for the js code to pass arguments around, fetch values etc. What I'd like to be able to do is something like: %tr %td .class1.class2.class3.classetc %ul#messages != this.partial('message.html.haml', { collection: messages }) Any combination I've tried with this has failed however. And I might have tried them all. If I could put a partial into that div I'd probably be set. And you can nest them as long as you use #ids instead of .classes. But if you use more than one class it breaks! I think that's the most accurate way of summing it up. How do you do this? I've checked out various templating solutions like mu.js and micro template like by John Resig. I earlier checked out this thread on templating engines. It's very possible I'm making some fundamental mistake here, I'm new to this. What's a good way to do this?

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  • xsl defining in xml

    - by aditya parikh
    My first few lines in movies.xml are as follows : <?xml version="1.0" encoding="ISO-8859-1"?> <?xml-stylesheet type="text/xsl" href="movies_style.xsl"?> <movies xmlns="http://www.w3schools.com" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.w3schools.com file:///B:/USC/Academic/DBMS/HWS/no3/movie_sch.xsd"> and first few lines in movies_style.xsl are as follows : <?xml version="1.0" encoding="UTF-8"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:fo="http://www.w3.org/1999/XSL/Format"> Problem is if remove schema file linking from movies.xml file and keep tag only as <movies> then proper styled table is shown as output else nothing is displayed in browser and error is displayed in console as: "Unsafe attempt to load URL file:///B:/USC/Academic/DBMS/HWS/no3/movies_style.xsl from frame with URL file:///B:/USC/Academic/DBMS/HWS/no3/movies.xml. Domains, protocols and ports must match." Looks like some namespace mistake. Can anyone point out exactly what ?

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  • Why might this work on my server but not my schools?

    - by Doug
    I created a captcha just now, and it works PERFECTLY on my own server. On the school's server, it doesn't generate an image. Why might this be? The difference in code is one line. *Edit:*Originally, it was working, but I deleted the directory by mistake and I do not know why did it suddenly work in the first place. Source code on school server: <?php session_save_path("/ichanged/this/path/for/this/post/"); session_start(); $img=imagecreatefromjpeg("bg.jpg"); if( empty($_SESSION['captcha_numbers']) ) { $captcha_numbers = 'error'; } else { $captcha_numbers = $_SESSION['captcha_numbers']; } $image_numbers=$captcha_numbers; $red=rand(100,150); $green=rand(100,255); $blue=rand(100,255); $color=imagecolorallocate($img,255-$red,255-$green,255-$blue); $text=imagettftext($img,12,rand(-7,7),rand(10,20),rand(20,30),$color,"fonts/M04.TTF",$image_numbers); header("Content-type:image/jpeg"); header("Content-Disposition:inline ; filename=secure.jpg"); imagejpeg($img); ?> Source code on my server: <?php session_start(); $img=imagecreatefromjpeg("bg.jpg"); if( empty($_SESSION['captcha_numbers']) ) { $captcha_numbers = 'error'; } else { $captcha_numbers = $_SESSION['captcha_numbers']; } $image_numbers=$captcha_numbers; $red=rand(100,150); $green=rand(100,255); $blue=rand(100,255); $color=imagecolorallocate($img,255-$red,255-$green,255-$blue); $text=imagettftext($img,12,rand(-7,7),rand(10,20),rand(20,30),$color,"fonts/M04.TTF",$image_numbers); header("Content-type:image/jpeg"); header("Content-Disposition:inline ; filename=secure.jpg"); imagejpeg($img); ?>

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  • Am I doing something wrong here (references in C++)?

    - by m4design
    I've been playing around with references (I'm still having issues in this regard). 1- I would like to know if this is an acceptable code: int & foo(int &y) { return y; // is this wrong? } int main() { int x = 0; cout << foo(x) << endl; foo(x) = 9; // is this wrong? cout << x << endl; return 0; } 2- Also this is from an exam sample: Week & Week::highestSalesWeek(Week aYear[52]) { Week max = aYear[0]; for(int i = 1; i < 52; i++) { if (aYear[i].getSales() > max.getSales()) max = aYear[i]; } return max; } It asks about the mistake in this code, also how to fix it. My guess is that it return a local reference. The fix is: Week & max = aYear[0]; Is this correct/enough?

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  • An array problem in C++

    - by manugupt1
    To access the array indice at the xth position we can use some sort of illustration as shown below #include<iostream> using namespace std; int main(){ float i[20]; for(int j=0;j<=20;j++) i[j]=0; } However the following piece of code does not work #include<iostream> using namespace std; float oldrand[55]; int jrand; void advance_random(){ int j1; float new_random; for(j1=0;j1<=23;j1++){ int temp = j1+30; new_random = (oldrand[j1]) - (oldrand[temp]); if(new_random <0.0) new_random = new_random+1; oldrand[j1] = new_random; } for(j1=24;j1<=54;j1++){ new_random[j1] = oldrand[j1] - oldrand[j1-23]; if(new_random[j1]<0.0) new_random[j1] = new_random + 1; oldrand[j1]=new_random; } } I recieve the following error ga.cpp:20: error: invalid types ‘float[int]’ for array subscript ga.cpp:21: error: invalid types ‘float[int]’ for array subscript ga.cpp:22: error: invalid types ‘float[int]’ for array subscript I am not able to find a mistake in my code please help me

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  • How to use form_tag to update params

    - by Tryskele
    I have been struggling with a problem in Rails for a couple of days and still could not find the solution. Could you help me with that? Problem: I have a search box that puts a :search_string entry in the params structure. I use a form_tag for that and it works fine. <% form_tag :controller=> 'items', :action => 'find' do %> <%= text_field_tag :search_string, params[:search_string] %> <% end %> The problem is when I want to add and update other params key-value (in another view), for instance :start_date, to filter the search_string result. Here is the code snipped that I use in the view: <% form_tag :controller=> "items", :action => "find", :params => params do %> <%= hidden_field_tag :date_start, '2010-04-01' %> <%= submit_tag 'April' %> <% end %> <% form_tag :controller=> "items", :action => "find", :params => params do %> <%= hidden_field_tag :date_start, '2010-03-01' %> <%= submit_tag 'March' %> <% end %> When I first click on "April" submit button, then the params is correctly passed to the controller (i.e. there is a params[:start_date]='April'). However when I try to click "March" button afterwards, the params[:start_date] is not updated. I definitely think this is a stupid newbie mistake, but I cannot figure out how to properly use the form_tag. Could you tell me if I am doing something work? Otherwise, could you advise me which is the best way to update the params using form_tag's ? Thank you very much in advance. Miquel

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  • Noise with multi-threaded raytracer

    - by herber88
    This is my first multi-threaded implementation, so it's probably a beginners mistake. The threads handle the rendering of every second row of pixels (so all rendering is handled within each thread). The problem persists if the threads render the upper and lower parts of the screen respectively. Both threads read from the same variables, can this cause any problems? From what I've understood only writing can cause concurrency problems... Can calling the same functions cause any concurrency problems? And again, from what I've understood this shouldn't be a problem... The only time both threads write to the same variable is when saving the calculated pixel color. This is stored in an array, but they never write to the same indices in that array. Can this cause a problem? Multi-threaded rendered image (Spam prevention stops me from posting images directly..) Ps. I use the exactly same implementation in both cases, the ONLY difference is a single vs. two threads created for the rendering.

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  • Converting WAR to EAR and other Glassfish stories

    - by Random
    Hello! I am really new in this so I hopefully don't make any terrible mistake. I apologize before hand if I have. In my project I was using tomcat and deploying WAR files. But now some bosses wants to deploy EAR files. So there we go. I first downloaded Glassfish (don't know if it's the apropiate application server for a newbie like me), instaled it and all (I even deployed the hello.war in the autodeploy _< ). Then prepared an EAR file. From what I know, I just need to create an Enterprise Application Project in Eclipse and add to the module my war file. This changes the application.xml file automatically (thanks eclipse project!). So I exported it to an EAR file and uploaded it to the glassfish server. Wonders of wonders, it doesn't work. I also tried deploying the old WAR file in this new shiny glassfish but it goes on http-404 not found error. The glassfish seems to say that my project is not in ~/domains/domain1/docroot. By the way I am using windows and I am aware of some problems between glassfish and windows due to some updating open files or such. So I have to questions: First, Am I doing the EAR package correctly? Second, Do I need to do some especial configuration to the glassfish server to deploy EAR and WAR files? Thanks!

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  • Cannot connect to MySQL server using JSP

    - by Dibya
    I just set foot on JSP. I started writing simple programs to display dates, system info. Then I tried to connect a MySQL database I have a free hosting account, but I am not able to connect to MySQL database. Here is my code: <%@ page import="java.sql.*" %> <%@ page import="java.io.*" %>  <html> <head> <title>Connection with mysql database</title> </head> <body> <h1>Connection status</h1> <% try { String connectionURL = "jdbc:mysql://mysql2.000webhost.com/a3932573_product"; Connection connection = null; Class.forName("com.mysql.jdbc.Driver").newInstance(); connection = DriverManager.getConnection(connectionURL, "a3932573_dibya", "******"); if(!connection.isClosed()) out.println("Successfully connected to " + "MySQL server using TCP/IP..."); connection.close(); }catch(Exception ex){ out.println("Unable to connect to database."); } %> </font> </body> </html> I am getting Message as Connection Status unable to connect to database. I have tested this connection using PHP using the same username, password and database name. Where am I making mistake?

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  • JQuery modal box form validation

    - by vikitor
    Hi, I was using a view to create an object for my specific project, but now I have to adapt this to another requirements, such as the creation of this object must be integrated in the creation of another one. The thing is, that this object must be created before starting to create the other one, and the way of doing it will be poping up a modal dialog box with JQuery with the form to create it. I've got to adapt the creation and it works fine, except for the validation messages. It is made in the controller like : if (not.NotName.Trim().Length == 0) { ModelState.AddModelError("NotName", "Name is required"); } if (_notification.checkIfExists(not.NotName, not.NotRecID)) { ModelState.AddModelError("NotName", "Notification already exists"); } And before with a normal view it worked fine, but now I'm not able to get the validation messages as I did. How can you get this validation messages thrown by the controller in the Modal Box? Because now when I made a mistake on purpose in the form in order to get the error it doesn't appear. I've seen the error is displayed in the site, because I've seen it on firebug, but it doesn't appear in my model box. How can I retrieve this errors? Do you know any tutorial that could help me with this? Thank you

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  • Problems with Window Functions Wndproc and about

    - by BrianHuangverinem
    I really having problems with this problem ,it would be nice if someone help me on this. Every time I try to build my source file the same errors occur every time for the two window functions CALLBACK Wndproc and CALLBACK About. error: "local function definitions are illegal" Can you tell me what mistake I made? LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { int wmId, wmEvent; PAINTSTRUCT ps; HDC hdc; wmId = LOWORD(wParam); wmEvent = HIWORD(wParam); switch (message) { case WM_COMMAND: // Parse the menu selections: switch (wmId) { case IDM_ABOUT: DialogBox(hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About); break; case IDM_EXIT: DestroyWindow(hWnd); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } break; case WM_PAINT: hdc = BeginPaint(hWnd, &ps); CaptureImage(hWnd); EndPaint(hWnd, &ps); break; case WM_DESTROY: PostQuitMessage(0); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } return 0; } // Message handler for about box. INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam) { UNREFERENCED_PARAMETER(lParam); switch (message) { case WM_INITDIALOG: return (INT_PTR)TRUE; case WM_COMMAND: if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL) { EndDialog(hDlg, LOWORD(wParam)); return (INT_PTR)TRUE; } break; } return (INT_PTR)FALSE; }

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  • getting nullpointer exception when click on button

    - by user1315187
    I am use a button and when u click this button a text field is automatic created and button status is automatic disable but if u click on disable button text field is automatic delete and button status is changed to enable.i going through this process. public class ConfigurationScreen extends MainScreen implements FieldChangeListener{ TextField tf_text; tf_text = new TextField(TextField.TYPE_PLAIN,img_text[1],img_text[0],TextField.FIELD_HCENTER); tf_text.setWidth(Display.getWidth()/2+20); ImageButton btn_en; btn_en = new ImageButton(imgs_tmintrvl1,"enable",ImageButton.FIELD_HCENTER); ImageButton btn_dis; btn_dis=new ImageButton(imgs_tmintrvl1,"Disable",ImageButton.FIELD_HCENTER); add(btn_en); btn_en.setChangeListener(this); public void fieldChanged(Field field, int context) { if( field==btn_en) { delete(btn_en); insert(btn_dis, 4); insert(tf_text, 5); System.out.println(ex); }else if (field == btn_dis){ delete(btn_dis); delete(tf_text); insert(btn_en, 4); System.out.println("Disable Button="+ex); } } But when i run this code i am getting null pointerr exception please help me where i am making mistake. Thanks in Advance

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  • How to detect that cookies are disabled in browser with AngularJS

    - by user2943082
    I use an AngularJS in my current project and try to implement feature which detects does cookies are disable in browser. I have tried to use an AngularJS module "ngCookies" for resolve this issue. The main idea of this feature is to try to create some cookie, then check does this cookie was created and show message if it wasn't. But it didn't worked. Controller: someProject.controller('CookieCtrl', ['$scope', '$cookieStore', function($scope, $cookieStore) { $scope.areCookiesEnabled = false; $cookieStore.put("TestCookie", "TestCookieText"); $scope.cookieValue = $cookieStore.get("TestCookie"); if ($scope.someValue) { $cookieStore.remove("TestCookie"); $scope.areCookiesEnabled = true; } }]); View: <div class="main" data-ng-controller="CookieCtrl"> <div class="warning_message" data-ng-show="!areCookiesEnabled"> <span data-ng-bind="areCookiesEnabled"></span> </div> </div> Can anybody tell me where is my mistake?

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