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  • Caching Authentication Data

    - by PartlyCloudy
    Hi, I'm currently implementing a REST web service using CouchDB and RESTlet. The RESTlet layer is mainly for authentication and some minor filtering of the JSON data served by CouchDB: Clients <= HTTP = [ RESTlet <= HTTP = CouchDB ] I'm using CouchDB also to store user login data, because I don't want to add an additional database server for that purpose. Thus, each request to my service causes two CouchDB requests conducted by RESTlet (auth data + "real" request). In order to keep the service as efficent as possible, I want to reduce the number of requests, in this case redundant requests for login data. My idea now is to provide a cache (i.e.LRU-Cache via LinkedHashMap) within my RESTlet application that caches login data, because HTTP caching will probabily not be enough. But how do I invalidate the cache data, once a user changes the password, for instance. Thanks to REST, the application might run on several servers in parallel, and I don't want to create a central instance just to cache login data. Currently, I save requested auth data in the cache and try to auth new requests by using them. If a authentication fails or there is now entry available, I'll dispatch a GET request to my CouchDB storage in order to obtain the actual auth data. So in a worst case, users that have changed their data will perhaps still be able to login with their old credentials. How can I deal with that? Or what is a good strategy to keep the cache(s) up-to-date in general? Thanks in advance.

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  • How much effort do you have to put in to get gains from using SSE?

    - by John
    Case One Say you have a little class: class Point3D { private: float x,y,z; public: operator+=() ...etc }; Point3D &Point3D::operator+=(Point3D &other) { this->x += other.x; this->y += other.y; this->z += other.z; } A naive use of SSE would simply replace these function bodies with using a few intrinsics. But would we expect this to make much difference? MMX used to involve costly state cahnges IIRC, does SSE or are they just like other instructions? And even if there's no direct "use SSE" overhead, would moving the values into SSE registers and back out again really make it any faster? Case Two Instead, you're working with a less OO-based code base. Rather than an array/vector of Point3D objects, you simply have a big array of floats: float coordinateData[NUM_POINTS*3]; void add(int i,int j) //yes it's unsafe, no overlap check... example only { for (int x=0;x<3;++x) { coordinateData[i*3+x] += coordinateData[j*3+x]; } } What about use of SSE here? Any better? In conclusion Is trying to optimise single vector operations using SSE actually worthwhile, or is it really only valuable when doing bulk operations?

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  • cast operator to base class within a thin wrapper derived class

    - by miked
    I have a derived class that's a very thin wrapper around a base class. Basically, I have a class that has two ways that it can be compared depending on how you interpret it so I created a new class that derives from the base class and only has new constructors (that just delegate to the base class) and a new operator==. What I'd like to do is overload the operator Base&() in the Derived class so in cases where I need to interpret it as the Base. For example: class Base { Base(stuff); Base(const Base& that); bool operator==(Base& rhs); //typical equality test }; class Derived : public Base { Derived(stuff) : Base(stuff) {}; Derived(const Base& that) : Base(that) {}; Derived(const Derived& that) : Base(that) {}; bool operator==(Derived& rhs); //special case equality test operator Base&() { return (Base&)*this; //Is this OK? It seems wrong to me. } }; If you want a simple example of what I'm trying to do, pretend I had a String class and String==String is the typical character by character comparison. But I created a new class CaseInsensitiveString that did a case insensitive compare on CaseInsensitiveString==CaseInsensitiveString but in all other cases just behaved like a String. it doesn't even have any new data members, just an overloaded operator==. (Please, don't tell me to use std::string, this is just an example!) Am I going about this right? Something seems fishy, but I can't put my finger on it.

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  • Distributing a bundle of files across an extranet

    - by John Zwinck
    I want to be able to distribute bundles of files, about 500 MB per bundle, to all machines on a corporate "extranet" (which is basically a few LANs connected using various private mechanisms, including leased lines and VPN). The total number of hosts is roughly 100, and the goal is to get a copy of the bundle from one host onto all the other hosts reliably, quickly, and efficiently. One important issue is that some hosts are grouped together on single fast LANs in which case the network I/O should be done once from one group to the next and then within each group between all the peers. This is as opposed to a strict central server system where multiple hosts might each fetch the same bundle over a slow link, rather than once via the slow link and then between each other quickly. A new bundle will be produced every few days, and occasionally old bundles will be deleted (but that problem can be solved separately). The machines in question happen to run recent Linuxes, but bonus points will go to solutions which are at least somewhat cross-platform (in which case the bundle might differ per platform but maybe the same mechanism can be used). That's pretty much it. I'm not opposed to writing some code to handle this, but it would be preferable if it were one of bash, Python, Ruby, Lua, C, or C++.

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  • Using collections/containers/catalogs in Domain Models

    - by devoured elysium
    Let's say I want to model a cinema. The cinema will have a couple of rooms(for example, 7), where the movies are being played. I wonder how should I design the domain model for this scenario. Should the Cinema class concept concept have a direct association with the 7 rooms? Should the Cinema class concept have an association with a catalog of the 7 rooms? Why? I am having some trouble understanding why in some places I see the first case and in some others I see something like the second case. If instead of rooms, I wanted to depict the relationship between Cinema and: Tickets to sell (today). Tickets already sold (today) Customers in the Cinema database The set of hours at which there are movies playing in a given room in the cinema. The set of places you can sit at in a room in the cinema. Should I use catalogs, should I connect them directly to the Cinema concept with a multiplicity of * in the target? Thanks

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  • private class calling a method from its outer class

    - by oxinabox.ucc.asn.au
    Ok, so I have a class for a "Advanced Data Structure" (in this case a kinda tree) SO I implimented a Iterator as a private class with in it. So the iterator needs to implement a remove function to remove the last retuirned element. now my ADT already impliments a remove function, and in this case there is very little (thinking about it, i think nothing) to be gain by implimenting a different remove function for the iterator. so how do I go about calling the remove from my ADT sketch of my struture: public class ADT { ... private class ADT_Iterator impliments java.util.Itorator{ ... public void remove(){ //where I want to call the ADT's remove function from } ... public void remove( Object paramFoo ) { ... } ... } So just calling remove(FooInstance) won't work (will it?) and this.remove(FooInstance) is the same thing. what do i call? (and changign the name of the ADT's remove function is not an option, as that AD T has to meet an Interace wich I am note at liberty to change) I could make both of them call a removeHelper functon, I guess...

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  • Multiple elements with the same name with SimpleXML and Java

    - by LouieGeetoo
    I'm trying to use SimpleXML to parse an XML document (an ItemLookupResponse for a book from the Amazon Product Advertising API) which contains the following element: <ItemAttributes> <Author>Shane Conder</Author> <Author>Lauren Darcey</Author> <Manufacturer>Pearson Educacion</Manufacturer> <ProductGroup>Book</ProductGroup> <Title>Android Wireless Application Development: Barnes & Noble Special Edition</Title> </ItemAttributes> My problem is that I don't know how to deal with the multiple possible Author elements. Here's what I have right now for the corresponding POJO (Plain Old Java Object), keeping in mind that it's not handling the case of multiple Authors: @Element public class ItemAttributes { @Element public String Author; @Element public String Manufacturer; @Element public String Title; } (I don't care about the ProductGroup, so it's not in the class -- I'm just setting SimpleXML's strict mode to off to allow for that.) I couldn't find an example in the documentation that corresponded with such a case. Using an ElementList with (inline=true) seemed along the right lines, but I didn't see how to do it for String (as opposed to a separate Author class, which I have no need for and don't see how it would even work). Here's a similar question and answer, but for PHP: php - simpleXML how to access a specific element with the same name as others? I don't know what the Java equivalent would be to the accepted answer. Thanks in advance.

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  • what does this attempted trojan horse code do?

    - by bstullkid
    It looks like this just sends a ping, but whats the point of that when you can just use ping? /* WARNING: this is someone's attempt at writing a malware trojan. Do not compile and *definitely* don't install. I added an exit as the first line to avoid mishaps - msw */ int main (int argc, char *argv[]) { exit(1); unsigned int pid = 0; char buffer[2]; char *args[] = { "/bin/ping", "-c", "5", NULL, NULL }; if (argc != 2) return 0; args[3] = strdup(argv[1]); for (;;) { gets(buffer); /* FTW */ if (buffer[0] == 0x6e) break; switch (pid = fork()) { case -1: printf("Error Forking\n"); exit(255); case 0: execvp(args[0], args); exit(1); default: break; } } return 255; }

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  • Should i enforce realloc check if the new block size is smaller than the initial ?

    - by nomemory
    Can realloc fail in this case ? int *a = NULL; a = calloc(100, sizeof(*a)); printf("1.ptr: %d \n", a); a = realloc(a, 50 * sizeof(*a)); printf("2.ptr: %d \n", a); if(a == NULL){ printf("Is it possible?"); } return (0); } The output in my case is: 1.ptr: 4072560 2.ptr: 4072560 So 'a' points to the same adress. So should i enforce realloc check ? Later edit: Using MinGW compiler under Windows XP. Is the behaviour similar with gcc on Linux ? Later edit 2: Is it OK to check this way ? int *a = NULL, *b = NULL; a = calloc(100, sizeof(*a)); b = realloc(a, 50 * sizeof(*a)); if(b == NULL){ return a; } a = b; return a;

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  • Is my method for avoiding dynamic_cast<> faster than dynamic_cast<> itself ?

    - by ereOn
    Hi, I was answering a question a few minutes ago and it raised to me another one: In one of my projects, I do some network message parsing. The messages are in the form of: [1 byte message type][2 bytes payload length][x bytes payload] The format and content of the payload are determined by the message type. I have a class hierarchy, based on a common class Message. To instanciate my messages, i have a static parsing method which gives back a Message* depending on the message type byte. Something like: Message* parse(const char* frame) { // This is sample code, in real life I obviously check that the buffer // is not NULL, and the size, and so on. switch(frame[0]) { case 0x01: return new FooMessage(); case 0x02: return new BarMessage(); } // Throw an exception here because the mesage type is unknown. } I sometimes need to access the methods of the subclasses. Since my network message handling must be fast, I decived to avoid dynamic_cast<> and I added a method to the base Message class that gives back the message type. Depending on this return value, I use a static_cast<> to the right child type instead. I did this mainly because I was told once that dynamic_cast<> was slow. However, I don't know exactly what it really does and how slow it is, thus, my method might be as just as slow (or slower) but far more complicated. What do you guys think of this design ? Is it common ? Is it really faster than using dynamic_cast<> ? Any detailed explanation of what happen under the hood when one use dynamic_cast<> is welcome !

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  • What's the best way to retrieve two pieces of data from an XML file?

    - by Morinar
    I've got an XML document that is in either a pre or post FO transformed state that I need to extract some information from. In the pre-case, I need to pull out two tags that represent the pageWidth and pageHeight and in the post case I need to extract the page-height and page-width parameters from a specific tag (I forget which one it is off the top of my head). What I'm looking for is an efficient/easily maintainable way to grab these two elements. I'd like to only read the document a single time fetching the two things I need. I initially started writing something that would use BufferedReader + FileReader, but then I'm doing string searching and it gets messy when the tags span multiple lines. I then looked at the DOMParser, which seems like it would be ideal, but I don't want to have to read the entire file into memory if I could help it as the files could potentially be large and the tags I'm looking for will nearly always be close to the top of the file. I then looked into SAXParser, but that seems like a big pile of complicated overkill for what I'm trying to accomplish. Anybody have any advice? Or simple implementations that would accomplish my goal? Thanks.

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  • Binary Search Tree for specific intent

    - by Luís Guilherme
    We all know there are plenty of self-balancing binary search trees (BST), being the most famous the Red-Black and the AVL. It might be useful to take a look at AA-trees and scapegoat trees too. I want to do deletions insertions and searches, like any other BST. However, it will be common to delete all values in a given range, or deleting whole subtrees. So: I want to insert, search, remove values in O(log n) (balanced tree). I would like to delete a subtree, keeping the whole tree balanced, in O(log n) (worst-case or amortized) It might be useful to delete several values in a row, before balancing the tree I will most often insert 2 values at once, however this is not a rule (just a tip in case there is a tree data structure that takes this into account) Is there a variant of AVL or RB that helps me on this? Scapegoat-trees look more like this, but would also need some changes, anyone who has got experience on them can share some thougts? More precisely, which balancing procedure and/or removal procedure would help me keep this actions time-efficient?

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  • How to get resultset with stored procedure calls over two linked servers?

    - by räph
    I have problems filling a temporary table with the resultset from a procedure call on a linked server, in which again a procedure on another server is called. I have a Stored Procedure sproc1 with the following code, which calls another procedure sproc2 on a linked server. SET @sqlCommand = 'INSERT INTO #tblTemp ( ModuleID, ParamID) ' + '( SELECT * FROM OPENQUERY(' + @targetServer + ', ' + '''SET FMTONLY OFF; EXEC ' + @targetDB + '.usr.sproc2 ' + @param + ''' ) )' exec ( @sqlCommand ) Now in the called sproc2 I again call a third procedure sproc3 on another linked server, which returns my resultset. SET @sqlCommand = 'EXEC ' + @targetServer +'.database.usr.sproc3 ' + @param exec ( @sqlCommand ) The whole thing doen't work, as I get an SQL error 7391 The operation could not be performed because OLE DB provider "%ls" for linked server "%ls" was unable to begin a distributed transaction. I already checked the hints at this microsoft article, but without success. But maybe, I can change the code in sproc1. Would there be some alternative to the temp table and the open query? Just calling stored procedures from server A to B to C and returning the resultset is working (I do this often in the application). But this special case with the temp table and openquery doesn't work! Or is it just not possible what I am trying to do? The microsft article states: Check the object you refer on the destination server. If it is a view or a stored procedure, or causes an execution of a trigger, check whether it implicitly references another server. If so, the third server is the source of the problem. Run the query directly on the third server. If you cannot run the query directly on the third server, the problem is not actually with the linked server query. Resolve the underlying problem first. Is this my case? PS: I can't avoid the architecture with the three servers.

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  • Bilinear interpolation - DirectX vs. GDI+

    - by holtavolt
    I have a C# app for which I've written GDI+ code that uses Bitmap/TextureBrush rendering to present 2D images, which can have various image processing functions applied. This code is a new path in an application that mimics existing DX9 code, and they share a common library to perform all vector and matrix (e.g. ViewToWorld/WorldToView) operations. My test bed consists of DX9 output images that I compare against the output of the new GDI+ code. A simple test case that renders to a viewport that matches the Bitmap dimensions (i.e. no zoom or pan) does match pixel-perfect (no binary diff) - but as soon as the image is zoomed up (magnified), I get very minor differences in 5-10% of the pixels. The magnitude of the difference is 1 (occasionally 2)/256. I suspect this is due to interpolation differences. Question: For a DX9 ortho projection (and identity world space), with a camera perpendicular and centered on a textured quad, is it reasonable to expect DirectX.Direct3D.TextureFilter.Linear to generate identical output to a GDI+ TextureBrush filled rectangle/polygon when using the System.Drawing.Drawing2D.InterpolationMode.Bilinear setting? For this (magnification) case, the DX9 code is using this (MinFilter,MipFilter set similarly): Device.SetSamplerState(0, SamplerStageStates.MagFilter, (int)TextureFilter.Linear); and the GDI+ path is using: g.InterpolationMode = InterpolationMode.Bilinear; I thought that "Bilinear Interpolation" was a fairly specific filter definition, but then I noticed that there is another option in GDI+ for "HighQualityBilinear" (which I've tried, with no difference - which makes sense given the description of "added prefiltering for shrinking") Followup Question: Is it reasonable to expect pixel-perfect output matching between DirectX and GDI+ (assuming all external coordinates passed in are equal)? If not, why not? Finally, there are a number of other APIs I could be using (Direct2D, WPF, GDI, etc.) - and this question generally applies to comparing the output of "equivalent" bilinear interpolated output images across any two of these. Thanks!

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  • stackoverflow tags and related tags

    - by parminder
    Hi Experts, I am working on a website where a user can add tags to their posted books. It is similar to stackover flow, but I am keeping my tags in differnt table. so here are the tables/class in linq to entities. Books { bookId, Title } Tags { Id Tag } BooksTags { Id BookId TagId } Here are few sample records. Books BookId Title 113421 A 113422 B Tags Id Tag 1 ASP 2 C# 3 CSS 4 VB 5 VB.NET 6 PHP 7 java 8 pascal BooksTags Id BookId TagId 1 113421 1 2 113421 2 3 113421 3 4 113421 4 5 113422 1 6 113422 4 7 113422 8 Question 1 : I need to write something in linq to entities queries which gives me data according to the tags say if I want bookIds where tagid =1 it should return bookid 113421 and 113422 as it exists in both the books, but If I ask data for tags 1 and 2 it should return only book 113421 as that is the only book where both the tags are present. Question 2 : I need tags and their count too to show in related tags, so in first case my related tags class should have following result. RelatedTags Tag Count 2 1 3 1 4 2 8 1 in the second case when two tags are requested the result should be like RelatedTags Tag Count 3 1 4 1 I have get the first thing working by converting a sql query in linqer, but that seems like a hell. so want to know if there is any better idea. I have used dyanmic where clause to include two tags. So if someone can help. It will be much appreciated. Thanks Parminder

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  • can not override showDialog in Activity tab

    - by hornetbzz
    Trying to downgrade my appl from android 2.2 (API 8) down to android 2.1 (API7), I'm facing some issues with dialog boxes. Based on this thread, I'm trying to catch these exceptions but can't override the showDialog method. I turned the Java compiler from 1.5 to 1.6 according to this answer to a similar issue, but no changes, Eclipse still returns : Cannot override the final method from Activity public class MyActivity extends Activity implements SeekBar.OnSeekBarChangeListener { // ... some stuffs @Override // here is the issue public void showDialog(int dialogId) { try { super.showDialog(dialogId); } catch (IllegalArgumentException e) { Log.e(ACTIVITY_TAG, "Error dialog"); } } @Override protected Dialog onCreateDialog(int id) { switch (id) { case DIALOG_ALERT: // Create out AlertDialog Builder builder = new AlertDialog.Builder(this); builder.setMessage(msg); builder.setCancelable(false); builder.setPositiveButton(GOTO_BOOK, new OkOnClickListener()); builder.setNegativeButton(STAY_HERE, new CancelOnClickListener()); AlertDialog dialog = builder.create(); dialog.show(); break; case DIALOG_ONCREATE: // Create out AlertDialog during the "onCreate" method (only "Ok" // button) Builder builder2 = new AlertDialog.Builder(getParent()); builder2.setMessage(msg); builder2.setCancelable(false); builder2.setPositiveButton(GO_BACK, new OkOnClickListener()); AlertDialog dialog2 = builder2.create(); dialog2.show(); break; } return super.onCreateDialog(id); } // ... some stuffs }

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  • File.Move does not inherit permissions from target directory?

    - by Joseph Kingry
    In case something goes wrong in creating a file, I've been writing to a temporary file and then moving to the destination. Something like: var destination = @"C:\foo\bar.txt"; var tempFile = Path.GetTempFileName(); using (var stream = File.OpenWrite(tempFile)) { // write to file here here } string backupFile = null; try { var dir = Path.GetDirectoryName(destination); if (!Directory.Exists(dir)) { Directory.CreateDirectory(dir); Util.SetPermissions(dir); } if (File.Exists(destination)) { backupFile = Path.Combine(Path.GetTempPath(), new Guid().ToString()); File.Move(destination, backupFile); } File.Move(tempFile, destination); if (backupFile != null) { File.Delete(backupFile); } } catch(IOException) { if(backupFile != null && !File.Exists(destination) && File.Exists(backupFile)) { File.Move(backupFile, destination); } } The problem is that the new "bar.txt" in this case does not inherit permissions from the "C:\foo" directory. Yet if I create a file via explorer/notepad etc directly in the "C:\foo" there's no issues, so I believe the permissions are correctly set on "C:\foo". Update Found Inherited permissions are not automatically updated when you move folders, maybe it applies to folders as well. Now looking for a way to force an update of file permissions. Is there a better way overall of doing this?

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  • Is there something like a Filestorage class to store files in?

    - by nebukadnezzar
    Is there something like a class that might be used to store Files and directories in, just like the way Zip files might be used? Since I haven't found any "real" class to write Zip files (real class as in real class), It would be nice to be able to store Files and Directories in a container-like file. A perfect API would probably look like this: int main() { ContainerFile cntf("myContainer.cnt", ContainerFile::CREATE); cntf.addFile("data/some-interesting-stuff.txt"); cntf.addDirectory("data/foo/"); cntf.addDirectory("data/bar/", ContainerFile::RECURSIVE); cntf.close(); } ... I hope you get the Idea. Important Requirements are: The Library must be crossplatform anything *GPL is not acceptable in this case (MIT and BSD License are) I already played with the thought of creating an Implentation based on SQLite (and its ability to store binary blobs). Unfortunately, it seems impossible to store Directory structures in a SQLite Database, which makes it pretty much useless in this case. Is it useless to hope for such a class library?

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  • Should I choose <button> element or css buttons?

    - by Kenny Bones
    Ok, here's the thing. I've done a webpage which contains forms and so I added buttons as elements and this works great. I created their own css classes and use graphics as background images for each of them. All working great (these are submit buttons btw) Anyway, I've also got a jQuery script from before that takes all a href hyperlinks and add content from a set div from an external file and adds to a div in my current page, all in one animation. But this would probably not work with form buttons? In any case I need to be able to have these buttons work as traditional hyperlinks anyway. So what do I do? I thought about using css-buttons alltogether, but I'm not able to have them stack vertically. Using float left or right just put the buttons outside of their parent containers (probably a different fix for that). But in any case, using css buttons, that wouldn't work as a submit button for the forms anyway would it? Should I perhaps use both form buttons and css buttons? What do you do?

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  • ASP.Net MVC, JS injection and System.ArgumentException - Illegal Characters in path

    - by Mose
    Hi, In my ASP.Net MVC application, I use custom error handling. I want to perform custom actions for each error case I meet in my application. So I override Application_Error, get the Server.GetLastError(); and do my business depending on the exception, the current user, the current URL (the application runs on many domains), the user IP, and many others. Obviousely, the application is often the target of hackers. In almost all the case it's not a problem to detect and manage it, but for some JS URL attacks, my error handling does not perform what I want it to do. Ex (from logs) : http://localhost:1809/Scripts/]||!o.support.htmlSerialize&&[1 When I got such an URL, an exception is raised when accessing the ConnectionStrings section in the web.config, and I can't even redirect to another URL. It leads to a "System.ArgumentException - Illegal Characters in path, etc." The screenshot below shows the problem : http://screencast.com/t/Y2I1YWU4 An obvious solution is to write a HTTP module to filter the urls before they reach my application, but I'd like to avoid it because : I like having the whole security being managed in one place (in the Application_Error() method) In the module I cannot access the whole data I have in the application itself (application specific data I don't want to debate here) Questions : Did you meet this problem ? How did you manage it ? Thanks for you suggestions, Mose

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  • Ubuntu server or Debian server (to run C++ apps developed on Ubuntu)

    - by skyeagle
    I have written a number of C++ server side daemons for my website, using my Ubuntu 9.10 dev machine. I am now about to venture out to look for a hosting provider etc. This is my problem: I have read on many posts (admittedly old posts) that Debian server is much more robust than Ubuntu server - is this till the case?. In particular, I am constantly "raising elephants" with my Ubuntu 9.10 - this is "ok" for home use, but for a website server, I would not be so forgiving. Also, there seems to be a new "patch" every few weeks - which I would not like on a server (I want to leave the server well alone, and let it get on with its business of serving pages). So in this instance Debian looks a more attractive proposition. I am worried that the C++ apps I have developed on Ubuntu may not be binary compatable with Debian (or I may need to install additional libraries/packages etc to get things to work), and I have zero experience with Debian. Additionally, I dont want to be grappling with the learning curve associated with a new OS, whilst trying to launch a new web site (I am assuming Debian UI is quite different from Ubuntu). In this case, the maxim "the devil you know is better than the one you dont", seems appropriate - and I find Ubuntu a more attractive proposition (atleast I know my apps will run without any probs etc). Can anyone provide some rational advice (based on actual experience), to help me decide which route to take - given the two (conflicting) trains of thought outlined above?

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  • NullPointerException with static variables

    - by tomekK
    I just hit very strange (to me) behaviour of java. I have following classes: public abstract class Unit { public static final Unit KM = KMUnit.INSTANCE; public static final Unit METERS = MeterUnit.INSTANCE; protected Unit() { } public abstract double getValueInUnit(double value, Unit unit); protected abstract double getValueInMeters(double value); } And: public class KMUnit extends Unit { public static final Unit INSTANCE = new KMUnit(); private KMUnit() { } //here are abstract methods overriden } public class MeterUnit extends Unit { public static final Unit INSTANCE = new MeterUnit(); private MeterUnit() { } ///abstract methods overriden } And my test case: public class TestMetricUnits extends TestCase { @Test public void testConversion() { System.out.println("Unit.METERS: " + Unit.METERS); System.out.println("Unit.KM: " + Unit.KM); double meters = Unit.KM.getValueInUnit(102.11, Unit.METERS); assertEquals(0.10211, meters, 0.00001); } } 1) MKUnit and MeterUnit are both singletons initialized statically, so during class loading. Constructors are private, so they can't be initialized anywhere else. 2) Unit class contains static final references to MKUnit.INSTANCE and MeterUnit.INSTANCE I would expect that: KMUnit class is loaded and instance is created. MeterUnit class is loaded and instance is created. Unit class is loaded and both KM and METERS variable are initialized, they are final so they cant be changed. But when I run my test case in console with maven my result is: T E S T S Running de.audi.echargingstations.tests.TestMetricUnits Unit.METERS: m Unit.KM: null Tests run: 3, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.089 sec <<< FAILURE! - in de.audi.echargingstations.tests.TestMetricUnits testConversion(de.audi.echargingstations.tests.TestMetricUnits) Time elapsed: 0.011 sec <<< ERROR! java.lang.NullPointerException: null at de.audi.echargingstations.tests.TestMetricUnits.testConversion(TestMetricUnits.java:29) Results : Tests in error: TestMetricUnits.testConversion:29 NullPointer And the funny part is that, when I run this test from eclipse via JUnit runner everything is fine, I have no NullPointerException and in console I have: Unit.METERS: m Unit.KM: km So the question is: what can be the reason that KM variable in Unit is null (and in the same time METERS is not null)

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  • how can a Win32 App plugin load its DLL in its own directory

    - by Jean-Denis Muys
    My code is a plugin for a specific Application, written in C++ using Visual Studio 8. It uses two DLL from an external provider. Unfortunately, my plugin fails to start because the DLLs are not found (I put them in the same directory as the plugin itself). When I manually move or copy the DLLs to the host application directory, then the plugin loads fine. This moving was deemed unacceptably cumbersome for the end user, and I am looking for a way for my plugin to load its DLLs transparently. What can I do? Relevant details: the host Application plugins are located in a directory mandated by the host application. That directory is not in the DLL search path and I don't control it. The plugin is itself packaged as a subdirectory of the plugin directory, holding the plugin code itself, but also any resource associated with the plugin (eg images, configuration files…). I control what's inside that subdirectory, called a "bundle", but not where it's located. the common plugin installation idiom for that App is for the end user to copy the plugin bundle to the plugin directory. This plugin is a port from the Macintosh version of the plugin. On the Mac there is no issue because each binary contains its own dynamic library search path, which I set as I needed to for my plugin binary. To set that on the Mac simply involves a project setting in the Xcode IDE. This is why I would hope for something similar in Visual Studio, but I could not find anything relevant. Moreover, Visual Studio's help was anything but, and neither was Google. A possible workaround would be for my code to explicitly tell Windows where to find the DLL, but I don't know how, and in any case, since my code is not even started, it hasn't got the opportunity to do so. As a Mac developer, I realize that I may be asking for something very elementary. If such is the case, I apologize, but I have run out of hair to pull out.

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  • UITableView only pushes to one controller

    - by Mitochondria
    So I have my UITableView, with 2 sections and 1 cell in each, and if I click the first one, it works, then the second one, it goes to the first controller. RootViewController is a navigationController, trying to push to ViewControllers. Here's the code for the tableView: // Customize the number of sections in the table view. - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView { return 2; } // Customize the number of rows in the table view. - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { if(section == 0) return 1; else return 1; } - (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{ if(section == 0){ return @"Terminal/SSH Guides"; }else{ return @"Cydia Tutorials"; } } // Customize the appearance of table view cells. - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; if (cell == nil) { cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease]; } // Set up the cell... if(indexPath.section == 0){ cell.text = @"Changing Password for root"; } else { cell.text = @"Hiding Sections"; } return cell; } - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { id newController; switch (indexPath.row) { case 0: newController = [[rootpassword alloc] initWithNibName:@"rootpassword" bundle:nil]; break; case 1: newController = [[hidingsections alloc] initWithNibName:@"hidingsections" bundle:nil]; break; default: break; } [self.navigationController pushViewController:newController animated:TRUE]; [tableView deselectRowAtIndexPath:indexPath animated:TRUE]; } I'm also having trouble adding more sections and rows/cells to sections. Thanks.

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  • Trouble with Router::url() when using named parameters

    - by sibidiba
    I'm generating plain simple links with CakePHP's HtmlHelper the following way: $html->link("Newest", array( 'controller' => 'posts', 'action' => 'listView', 'page'=> 1, 'sort'=>'Question.created', 'direction'=>'desc', )); Having the following route rule: Router::connect('/foobar/*',array( 'controller' => 'posts', 'action' => 'listView' )); The link is nicely generated as /foobar/page:1/sort:Question.created/direction:desc. Just as I want, it uses my URL prefix instead of controller/action names. However, for some links I must add named parameters like this: $html->link("Newest", array( 'controller' => 'posts', 'action' => 'listView', 'page'=> 1, 'sort'=>'Question.created', 'direction'=>'desc', 'namedParameter' => 'namedParameterValue' )); The link in this case points to /posts/listView/page:1/sort:Question.created/direction:desc/namedParameter:namedParameterValue. But I do not want to have contoller/action names in my URL-s, why is Cake ignoring in this case my routers configuration?

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