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  • How can i inject servletcontext in spring

    - by M.R.
    I need to write a junit test for a rather complex application which runs in a tomcat. I wrote a class which builds up my spring context. private static ApplicationContext springContext = null; springContext = new ClassPathXmlApplicationContext( new String[] {"beans"....}); In the application there is a call: public class myClass implements ServletContextAware { .... final String folder = servletContext.getRealPath("/example"); ... } which breaks everything, because the ServletContext is null. I have started to build a mock object: static ServletConfig servletConfigMock = createMock(ServletConfig.class); static ServletContext servletContextMock = createMock(ServletContext.class); @BeforeClass public static void setUpBeforeClass() throws Exception { expect(servletConfigMock.getServletContext()).andReturn(servletContextMock).anyTimes(); expect(servletContextMock.getRealPath("/example")).andReturn("...fulllpath").anyTimes(); replay(servletConfigMock); replay(servletContextMock); } Is there a simple methode to inject the ServletContext or to start the tomcat with a deployment descriptor at the runtime of the junit test? I am using: spring, maven, tomcat 6 and easymock for the mock objects.

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  • StackOverFlowException - but oviously NO recursion/endless loop

    - by user567706
    Hi there, I'm now blocked by this problem the entire day, read thousands of google results, but nothing seems to reflect my problem or even come near to it... i hope any of you has a push into the right direction for me. I wrote a client-server-application (so more like 2 applications) - the client collects data about his system, as well as a screenshot, serializes all this into a XML stream (the picture as a byte[]-array]) and sends this to the server in regular intervals. The server receives the stream (via tcp), deserializes the xml to an information-object and shows the information on a windows form. This process is running stable for about 20-25 minutes at a submission interval of 3 seconds. When observing the memory usage there's nothing significant to see, also kinda stable. But after these 20-25 mins the server throws a StackOverflowException at the point where it deserializes the tcp-stream, especially when setting the Image property from the byte[]-array. I thoroughly searched for recursive or endless loops, and regarding the fact that it occurs after thousands of sucessfull intervals, i could hardly imagine that. public byte[] ImageBase { get { MemoryStream ms = new MemoryStream(); _screen.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg); return ms.GetBuffer(); } set { if (_screen != null) _screen.Dispose(); //preventing well-known image memory leak MemoryStream ms = new MemoryStream(value); try { _screen = Image.FromStream(ms); //<< EXCEPTION THROWING HERE } catch (StackOverflowException ex) //thx to new CLR management this wont work anymore -.- { Console.WriteLine(ex.Message + Environment.NewLine + ex.StackTrace); } ms.Dispose(); ms = null; } } I hope that more code would be unnecessary, or it could get very complex... Please help, i have no clue at all anymore thx Chris

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  • How is jQuery so fast?

    - by ClarkeyBoy
    Hey, I have a rather large application which, on the admin frontend, takes a few seconds to load a page because of all the pageviews that it has to load into objects before displaying anything. Its a bit complex to explain how the system works, but a few of my other questions explains the system in great detail. The main difference between what they say and the current system is that the customer frontend no longer loads all the pageviews into objects when a customer first views the page - it simply adds the pageview to the database and creates an object in an unsynchronised list... to put it simply, when a customer views a page it no longer loads all the pageviews into objects; but the admin frontend still does. I have been working on some admin tools on the customer frontend recently, so if an administrator clicks the description of an item in the catalogue then the right hand column will display statistics and available actions for the selected item. To do this the page which gets loaded (through $('action-container').load(bla bla bla);) into the right hand column has to loop through ALL the pageviews - this ultimately means that ALL the pageviews are loaded into objects if they haven't been already. For some reason this loads really REALLY fast. The difference in speed is only like a second on my dev site, but the live site has thousands of pageviews so the difference is quite big... So my question is: why is it that the admin frontend loads so slowly while using $(bla).load(bla); is so fast? I mean whatever method jQuery uses, can't browsers use this method too and load pages super-fast? Obviously not as someone would've done that by now - but I am interested to know just why the difference is so big... is it just my system or is there a major difference in speed between the browser getting a page and jQuery getting a page? Do other people experience the same kind of differences? Thanks in advance, Regards, Richard

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  • Subversion versus Vault

    - by WebDude
    I'm currently reviewing the benefits of moving from SVN to a SourceGear Vault. Has anyone got advice or a link to a detailed comparison between the two? Bear in mind I would have to move my current Source Control system across which works strongly in SVN's favor Here is some info I have found out thus far from my own investigations. I have been taking some time tests between the two and vault seems to perform most operations much faster. Time tests used the same server as the repository, the same workstation client, and the same project. Time Comparisons SVN Add/Commit    12:30 Get Latest Revision    5:35 Tagging/Labelling    0:01 Branching    N/A - I don't think true branching exists in SVN Vault Add/Commit    4:45 Get Latest Revision    0:51 Tagging/Labelling    0:30 Branching    3:23 (can't get this to format correctly) I also found an online source comparing some other points. This is the kind of information i'm looking for. Usage Comparisons Subversion is edit/merge/commit only. Vault allows you to do either edit/merge/commit or checkout/edit/checkin. Vault looks and acts just like VSS, which makes the learning curve effectively zero for VSS users. Vault has a VS plugin, but it only works if you're going to run in checkout-mode. Subversion has clients for pretty much every OS you can imagine; Vault has a GUI client for Windows and a command line client for Mono. Both will support remote work, since both use HTTP as their transport (Subversion uses extended DAV, Vault uses SOAP). Subversion installation, especially w/ Apache, is more complex. Subversion has a lot of third party support. Vault has just a few things. My question Has anyone got advice or a link to a detailed comparison between the two?

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  • Address Match Key Algorithm

    - by sestocker
    I have a list of addresses in two separate tables that are slightly off that I need to be able to match. For example, the same address can be entered in multiple ways: 110 Test St 110 Test St. 110 Test Street Although simple, you can imagine the situation in more complex scenerios. I am trying to develop a simple algorithm that will be able to match the above addresses as a key. For example. the key might be "11TEST" - first two of 110, first two of Test and first two of street variant. A full match key would also include first 5 of the zipcode as well so in the above example, the full key might look like "11TEST44680". I am looking for ideas for an effective algorithm or resources I can look at for considerations when developing this. Any ideas can be pseudo code or in your language of choice. We are only concerned with US addresses. In fact, we are only looking at addresses from 250 zip codes from Ohio and Michigan. We also do not have access to any postal software although would be open to ideas for cost effective solutions (it would essentially be a one time use). Please be mindful that this is an initial dump of data from a government source so suggestions of how users can clean it are helpful as I build out the application but I would love to have the best initial I possibly can by being able to match addresses as best as possible.

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  • What Is The Proper Location For One-Offs In VCS Repos?

    - by Joe Clark
    I have recently started using Mercurial as our VCS. Over the years, I have used RCS, CVS, and - for the last 5 years - SVN. Back 13 years ago, when I primarily used CVS and RCS, large projects went into CVS and one-offs were edited in place on the specific server and stored in RCS. This worked well as the one-offs were usually specific to the server and the servers were backed up nightly. Jump forward a decade and a lot of the one-off scripts became less centralized - they might be needed on any server at some random time. This was also OK, because now I was a begrudging SVN user. Everything (except for docs) got dumped into one repo. Jump to 2010. Now I am using Mercurial and am putting large projects in their own repo again. But what to do with the one-offs? The options as I see them: A repo for each script. It seems a bit cluttered to create a repo for every one page script that might get ran once a year. RCS Not an option. There are many possible servers that might need a specific script. Continuing to use SVN just for one-offs. No. There no advantage I see over the next option. Create a repo in Mercurial named "one-offs". This seems the most workable. The last option seems the best to me - however; is there a best practice regarding this? You also might be wondering if these scripts are truly one-offs if they will be reused. Some of them may be reused 6 months or a year from now - some, never. However, nearly all of them involve several man-hours of work due to either complex logic or extensive error checking. Simply discarding them is not efficient.

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  • iPhone programming - problem with CoreFoundation forking, PLEASE for the love of god help! lol

    - by Tom
    Hello all, I've been working on an iPhone for several months. It's a 2d shooting game akin to the old Smash TV type games. I'm doing everything alone and it has come out well so far, but now I am getting unpredictable crashes which seem to be related to CoreFoundation forking and not exec()ing, as the message THE_PROCESS_HAS_FORKED_AND_YOU_CANNOT_USE_THIS_COREFOUNDATION_FUNCTIONA LITY_YOU_MUST_EXEC__ always shows up somewhere in the debugger. Usually it shows up around a CFRunLoopRunSpecific and is related to either a timer firing or _InitializeTouchTapCount. I cannot figure out exactly what is causing the fork to occur. My main game loop is running on a timer, first updating all the logic and then drawing everything with openGL. There is nothing highly complex or unusual. I understand you cannot make CF calls on the childside of a fork, or access shared memory and things like that. I am not explicitly trying to fork anything. My question is: can anyone tell me what type of activity might cause CoreFoundation to randomly fork like this? I'd really like to finish this game and I don't know how to solve this problem. Thanks for any help.

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  • How have you successfully implemented MessageBox.Show() functionality in MVVM?

    - by Edward Tanguay
    I've got a WPF application which calls MessageBox.Show() way back in the ViewModel (to check if the user really wants to delete). This actually works, but goes against the grain of MVVM since the ViewModel should not explicitly determine what happens on the View. So now I am thinking how can I best implement the MessageBox.Show() functionality in my MVVM application, options: I could have a message with the text "Are you sure...?" along with two buttons Yes and No all in a Border in my XAML, and create a trigger on the template so that it is collapsed/visible based on a ViewModelProperty called AreYourSureDialogueBoxIsVisible, and then when I need this dialogue box, assign AreYourSureDialogueBoxIsVisible to "true", and also handle the two buttons via DelegateCommand back in my ViewModel. I could also somehow try to handle this with triggers in XAML so that the Delete button actually just makes some Border element appear with the message and buttons in it, and the Yes button did the actually deleting. Both solutions seem to be too complex for what used to be a couple lines of code with MessageBox.Show(). In what ways have you successfully implemented Dialogue Boxes in your MVVM applications?

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  • Where should 'CreateMap' statements go?

    - by jonathanconway
    I frequently use AutoMapper to map Model (Domain) objects to ViewModel objects, which are then consumed by my Views, in a Model/View/View-Model pattern. This involves many 'Mapper.CreateMap' statements, which all must be executed, but must only be executed once in the lifecycle of the application. Technically, then, I should keep them all in a static method somewhere, which gets called from my Application_Start() method (this is an ASP.NET MVC application). However, it seems wrong to group a lot of different mapping concerns together in one central location. Especially when mapping code gets complex and involves formatting and other logic. Is there a better way to organize the mapping code so that it's kept close to the ViewModel that it concerns? (I came up with one idea - having a 'CreateMappings' method on each ViewModel, and in the BaseViewModel, calling this method on instantiation. However, since the method should only be called once in the application lifecycle, it needs some additional logic to cache a list of ViewModel types for which the CreateMappings method has been called, and then only call it when necessary, for ViewModels that aren't in that list.)

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  • Machine Learning Algorithm for Predicting Order of Events?

    - by user213060
    Simple machine learning question. Probably numerous ways to solve this: There is an infinite stream of 4 possible events: 'event_1', 'event_2', 'event_4', 'event_4' The events do not come in in completely random order. We will assume that there are some complex patterns to the order that most events come in, and the rest of the events are just random. We do not know the patterns ahead of time though. After each event is received, I want to predict what the next event will be based on the order that events have come in in the past. The predictor will then be told what the next event actually was: Predictor=new_predictor() prev_event=False while True: event=get_event() if prev_event is not False: Predictor.last_event_was(prev_event) predicted_event=Predictor.predict_next_event(event) The question arises of how long of a history that the predictor should maintain, since maintaining infinite history will not be possible. I'll leave this up to you to answer. The answer can't be infinte though for practicality. So I believe that the predictions will have to be done with some kind of rolling history. Adding a new event and expiring an old event should therefore be rather efficient, and not require rebuilding the entire predictor model, for example. Specific code, instead of research papers, would add for me immense value to your responses. Python or C libraries are nice, but anything will do. Thanks! Update: And what if more than one event can happen simultaneously on each round. Does that change the solution?

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  • Where can I find clear examples of MVC?

    - by Tom
    I've read a couple of things about MVCs but I still don't understand when they should be used and when they shouldn't be used. I am looking for clear examples that say things like "if you're developing this then you should use MVC, like this" and "if you're developing this, you shouldn't use MVC." Most of the examples I've seen rely on complex frameworks which have already implemented everything and you have to learn the framework and use it a lot to understand what's really happening. To many programmers, phrasings such as "UI business logic" sound like marketing terms — for example, the words "Instead the View binds directly to a Presentation Model" are used in this post. I am aware of the dangers that may lurk in the shadows as MVC is a concept and everyone feels like they know it best, yet nobody really knows exactly how to use it because there may be a lot of variables involved and everyone is allowed to have a different perspective on how to dissect a project into the Model, the View and the Controller. There is a lot of theory out there but very few clear examples. What I'm looking for are not "the best" ways of doing it so this should not be considered as subjective; I'm looking for different simple implementations that would allow me to decide on my own which are the best approaches. Succinctly: What are good on-line resources that present pro and con arguments to using MVC in various situations and provide clear examples to help the reader understand the concept?

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  • Why so much stack space used for each recursion?

    - by Harvey
    I have a simple recursive function RCompare() that calls a more complex function Compare() which returns before the recursive call. Each recursion level uses 248 bytes of stack space which seems like way more than it should. Here is the recursive function: void CMList::RCompare(MP n1) // RECURSIVE and Looping compare function { auto MP ne=n1->mf; while(StkAvl() && Compare(n1=ne->mb)) RCompare(n1); // Recursive call ! } StkAvl() is a simple stack space check function that compares the address of an auto variable to the value of an address near the end of the stack stored in a static variable. It seems to me that the only things added to the stack in each recursion are two pointer variables (MP is a pointer to a structure) and the stuff that one function call stores, a few saved registers, base pointer, return address, etc., all 32-bit (4 byte) values. There's no way that is 248 bytes is it? I don't no how to actually look at the stack in a meaningful way in Visual Studio 2008. Thanks

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  • Generating the SQL query plan takes 5 minutes, the query itself runs in milliseconds. What's up?

    - by TheImirOfGroofunkistan
    I have a fairly complex (or ugly depending on how you look at it) stored procedure running on SQL Server 2008. It bases a lot of the logic on a view that has a pk table and a fk table. The fk table is left joined to the pk table slightly more than 30 times (the fk table has a poor design - it uses name value pairs that I need to flatten out. Unfortunately, it's 3rd party and I cannot change it). Anyway, it had been running fine for weeks until I periodically noticed a run that would take 3-5 minutes. It turns out that this is the time it takes to generate the query plan. Once the query plan exists and is cached, the stored procedure itself runs very efficiently. Things run smoothly until there is a reason to regenerate and cache the query plan again. Has anyone seen this? Why does it take so long to generate the plan? Are there ways to make it come up with a plan faster?

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  • Unit tests for deep cloning

    - by Will Dean
    Let's say I have a complex .NET class, with lots of arrays and other class object members. I need to be able to generate a deep clone of this object - so I write a Clone() method, and implement it with a simple BinaryFormatter serialize/deserialize - or perhaps I do the deep clone using some other technique which is more error prone and I'd like to make sure is tested. OK, so now (ok, I should have done it first) I'd like write tests which cover the cloning. All the members of the class are private, and my architecture is so good (!) that I haven't needed to write hundreds of public properties or other accessors. The class isn't IComparable or IEquatable, because that's not needed by the application. My unit tests are in a separate assembly to the production code. What approaches do people take to testing that the cloned object is a good copy? Do you write (or rewrite once you discover the need for the clone) all your unit tests for the class so that they can be invoked with either a 'virgin' object or with a clone of it? How would you test if part of the cloning wasn't deep enough - as this is just the kind of problem which can give hideous-to-find bugs later?

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  • Matplotlib canvas drawing

    - by Morgoth
    Let's say I define a few functions to do certain matplotlib actions, such as def dostuff(ax): ax.scatter([0.],[0.]) Now if I launch ipython, I can load these functions and start a new figure: In [1]: import matplotlib.pyplot as mpl In [2]: fig = mpl.figure() In [3]: ax = fig.add_subplot(1,1,1) In [4]: run functions # run the file with the above defined function If I now call dostuff, then the figure does not refresh: In [6]: dostuff(ax) I have to then explicitly run: In [7]: fig.canvas.draw() To get the canvas to draw. Now I can modify dostuff to be def dostuff(ax): ax.scatter([0.],[0.]) ax.get_figure().canvas.draw() This re-draws the canvas automatically. But now, say that I have the following code: def dostuff1(ax): ax.scatter([0.],[0.]) ax.get_figure().canvas.draw() def dostuff2(ax): ax.scatter([1.],[1.]) ax.get_figure().canvas.draw() def doboth(ax): dostuff1(ax) dostuff2(ax) ax.get_figure().canvas.draw() I can call each of these functions, and the canvas will be redrawn, but in the case of doboth(), it will get redrawn multiple times. My question is: how could I code this, such that the canvas.draw() only gets called once? In the above example it won't change much, but in more complex cases with tens of functions that can be called individually or grouped, the repeated drawing is much more obvious, and it would be nice to be able to avoid it. I thought of using decorators, but it doesn't look as though it would be simple. Any ideas?

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  • Ajax call to parent window after form submission

    - by David
    Hi all, Pardon the complicated title. Here's my situation: I'm working on a Grails app, and using jQuery for some of the more complex UI stuff. The way the system is set up, I have an item, which can have various files (user-supplied) associated with it. On my Item/show view, there is a link to add a file. This link pops up a jQuery modal dialog, which displays my file upload form (a remote .gsp). So, the user selects the file and enters a comment, and when the form is submitted, the dialog gets closed, and the list of files on the Item/show view is refreshed. I was initially accomplishing this by adding onclick="javascript:window.parent.$('#myDialog').dialog('close');" to my submit button. This worked fine, but when submitting some larger files, I end up with a race condition where the dialog closes and the file list is refreshed before the new file is saved, and so the list of files is out of date (the file still gets saved properly). So my question is, what is the best way to ensure that the dialog is not closed until after the form submit operation completes? I've tried using the <g:formRemote tag in Grails, and closing the dialog in the "after" attribute (according to the Grails docs, the script is called after form submission), but I receive an error (taken from FireBug) stating that window.parent.$('#myDialog').dialog is not a function Is this a simple JavaScript/Grails syntax issue that I'm missing here, or am I going about this entirely wrong? Thanks so much for your time and assistance!

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  • Linq: the linked objects are null, why?

    - by user46503
    Hello, I have several linked tables (entities). I'm trying to get the entities using the following linq: ObjectQuery<Location> locations = context.Location; ObjectQuery<ProductPrice> productPrice = context.ProductPrice; ObjectQuery<Product> products = context.Product; IQueryable<ProductPrice> res1 = from pp in productPrice join loc in locations on pp.Location equals loc join prod in products on pp.Product equals prod where prod.Title.ToLower().IndexOf(Word.ToLower()) > -1 select pp; This query returns 2 records, ProductPrice objects that have linked object Location and Product but they are null and I cannot understand why. If I try to fill them in the linq as below: res = from pp in productPrice join loc in locations on pp.Location equals loc join prod in products on pp.Product equals prod where prod.Title.ToLower().IndexOf(Word.ToLower()) > -1 select new ProductPrice { ProductPriceId = pp.ProductPriceId, Product = prod }; I have the exception "The entity or complex type 'PBExplorerData.ProductPrice' cannot be constructed in a LINQ to Entities query" Could someone please explain me what happens and what I need to do? Thanks

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  • GAE python database object design for simple list of values

    - by Joey
    I'm really new to database object design so please forgive any weirdness in my question. Basically, I am use Google AppEngine (Python) and contructing an object to track user info. One of these pieces of data is 40 Achievement scores. Do I make a list of ints in the User object for this? Or do I make a separate entity with my user id, the achievement index (0-39) and the score and then do a query to grab these 40 items every time I want to get the user data in total? The latter approach seems more object oriented to me, and certainly better if I extend it to have more than just scores for these 40 achievements. However, considering that I might not extend it, should I even consider just doing a simple list of 40 ints in my user data? I would then forgo doing a query, getting the sorted list of achievements, reading the score from each one just to process a response etc. Is doing this latter approach just such a common practice and hand-waved as not even worth batting an eyelash at in terms of thinking it might be more costly or complex processing wise?

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  • Make WebStart Java desktop application to start on system startup on Windows and Mac

    - by parxier
    I developed small cross-platform (Windows and Mac) SWT desktop application. It is distributed with WebStart. So far so good, everything works. I've got a new requirement to make my app start on system startup (with no user interaction). What is the best way to accomplish that? In JNLP file I've got this: <shortcut online="false"> <desktop/> <menu submenu="CompanyName"/> </shortcut> On Windows WebStart creates a desktop link [app_name].lnk and it points to javaws.exe and then some Java cache file as a parameter with funny name like ..\Sun\Java\Deployment\cache\6.0\4\2c0a6a781-213476. I can possibly programmatically find that link on user's machine by name... erm... and then copy it into user's Startup folder. I can see a problem here though as user can disable WebStart desktop shortcut creation option all together. On Mac WebStart pops up a dialog to prompt user for the location where to create an [app_name].app (user is allowed to change link name there!) file that launches an application. On Mac I don't event know where the Startup folder is located (and it seems to be much more complex there). Is there Java library out there that abstracts start app on system startup concept on different platforms as SWT does for GUI abstraction?

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  • SQL database problems with addressbook table design

    - by Sebastian Hoitz
    Hello! I am writing a addressbook module for my software right now. I have the database set up so far that it supports a very flexible address-book configuration. I can create n-entries for every type I want. Type means here data like 'email', 'address', 'telephone' etc. I have a table named 'contact_profiles'. This only has two columns: id Primary key date_created DATETIME And then there is a table called contact_attributes. This one is a little more complex: id PK #profile (Foreign key to contact_profiles.id) type VARCHAR describing the type of the entry (name, email, phone, fax, website, ...) I should probably change this to a SET later. value Text (containing the value for the attribute). I can now link to these profiles, for example from my user's table. But from here I run into problems. At the moment I would have to create a JOIN for each value that I want to retrieve. Is there a possibility to somehow create a View, that gives me a result with the type's as columns? So right now I would get something like #profile type value 1 email [email protected] 1 name Sebastian Hoitz 1 website domain.tld But it would be nice to get a result like this: #profile email name website 1 [email protected] Sebastian Hoitz domain.tld The reason I do not want to create the table layout like this initially is, that there might always be things to add and I want to be able to have multiple attributes of the same type. So do you know if there is any possibility to convert this dynamically? If you need a better description please let me know. Thank you!

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  • Limit foreign key choices in select in an inline form in admin

    - by mightyhal
    Edited :-) Hopefully a bit clearer now. The logic is of the model is: A Building has many Rooms A Room may be inside another Room (a closet, for instance--ForeignKey on 'self') A Room can only in inside of another Room in the same building (this is the tricky part) Here's the code I have: #spaces/models.py from django.db import models class Building(models.Model): name=models.CharField(max_length=32) def __unicode__(self): return self.name class Room(models.Model): number=models.CharField(max_length=8) building=models.ForeignKey(Building) inside_room=models.ForeignKey('self',blank=True,null=True) def __unicode__(self): return self.number and: #spaces/admin.py from ex.spaces.models import Building, Room from django.contrib import admin class RoomAdmin(admin.ModelAdmin): pass class RoomInline(admin.TabularInline): model = Room extra = 2 class BuildingAdmin(admin.ModelAdmin): inlines=[RoomInline] admin.site.register(Building, BuildingAdmin) admin.site.register(Room) The inline will display only rooms in the current building (which is what I want). The problem, though, is that for the inside_room drop down, it displays all of the rooms in the Rooms table (including those in other buildings). In the inline of rooms, I need to limit the inside_room choices to only rooms which are in the current building being displayed by the main form. I can't figure out a way to do it with either a limit_choices_to in the model, nor can I figure out how exactly to override the admin's inline formset properly (I feel like I should be somehow create a custom inline form, pass the building_id of the main form to the custom inline, then limit the queryset for the field's choices based on that--but I just can't wrap my head around how to do it). Maybe this is too complex for the admin site, but it seems like something that would be generally useful... Thanks again for your help!

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  • Convert 4 bytes to int

    - by Oscar Reyes
    I'm reading a binary file like this: InputStream in = new FileInputStream( file ); byte[] buffer = new byte[1024]; while( ( in.read(buffer ) > -1 ) { int a = // ??? } What I want to do it to read up to 4 bytes and create a int value from those but, I don't know how to do it. I kind of feel like I have to grab 4 bytes at a time, and perform one "byte" operation ( like << & FF and stuff like that ) to create the new int What's the idiom for this? EDIT Ooops this turn out to be a bit more complex ( to explain ) What I'm trying to do is, read a file ( may be ascii, binary, it doesn't matter ) and extract the integers it may have. For instance suppose the binary content ( in base 2 ) : 00000000 00000000 00000000 00000001 00000000 00000000 00000000 00000010 The integer representation should be 1 , 2 right? :- / 1 for the first 32 bits, and 2 for the remaining 32 bits. 11111111 11111111 11111111 11111111 Would be -1 and 01111111 11111111 11111111 11111111 Would be Integer.MAX_VALUE ( 2147483647 )

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  • SQL Server CLR stored procedures in data processing tasks - good or evil?

    - by Gart
    In short - is it a good design solution to implement most of the business logic in CLR stored procedures? I have read much about them recently but I can't figure out when they should be used, what are the best practices, are they good enough or not. For example, my business application needs to parse a large fixed-length text file, extract some numbers from each line in the file, according to these numbers apply some complex business rules (involving regex matching, pattern matching against data from many tables in the database and such), and as a result of this calculation update records in the database. There is also a GUI for the user to select the file, view the results, etc. This application seems to be a good candidate to implement the classic 3-tier architecture: the Data Layer, the Logic Layer, and the GUI layer. The Data Layer would access the database The Logic Layer would run as a WCF service and implement the business rules, interacting with the Data Layer The GUI Layer would be a means of communication between the Logic Layer and the User. Now, thinking of this design, I can see that most of the business rules may be implemented in a SQL CLR and stored in SQL Server. I might store all my raw data in the database, run the processing there, and get the results. I see some advantages and disadvantages of this solution: Pros: The business logic runs close to the data, meaning less network traffic. Process all data at once, possibly utilizing parallelizm and optimal execution plan. Cons: Scattering of the business logic: some part is here, some part is there. Questionable design solution, may encounter unknown problems. Difficult to implement a progress indicator for the processing task. I would like to hear all your opinions about SQL CLR. Does anybody use it in production? Are there any problems with such design? Is it a good thing?

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  • How to update QStandartItemModel without freezing the main UI

    - by user1044002
    I'm starting to learn PyQt4 and have been stuck on something for a long time now and can't figure it out myself: Here is the concept: There is a TreeView with custom QStandartItemModel, which gets rebuild every couple of seconds, and can have a lot (hundreds at least) of entries, there also will be additional delegates for the different columns etc. It's fairly complex and the building time for even plain model, without delegates, goes up to .3 sec, which makes the TreeView to freeze. Please advice me for the best approach on solving this. I was thing of somehow building the model in different thread, and eventually sending it to the TreeView, where it would just perform setModel() with the new one, but couldn't make that work. here is some code that may illustrate the problem a bit: from PyQt4.QtCore import * from PyQt4.QtGui import * import sys, os, re, time app = QApplication(sys.argv) REFRESH = 1 class Reloader_Thread(QThread): def __init__(self, parent = None): QThread.__init__(self, parent) self.loaders = ['\\', '--', '|', '/', '--'] self.emit(SIGNAL('refresh')) def run(self): format = '|%d/%b/%Y %H:%M:%S| ' while True: self.emit(SIGNAL('refresh')) self.sleep(REFRESH) class Model(QStandardItemModel): def __init__(self, viewer=None): QStandardItemModel.__init__(self,None) self.build() def build(self): stTime = time.clock() newRows = [] for r in range(1000): row = [] for c in range(12): item = QStandardItem('%s %02d%02d' % (time.strftime('%H"%M\'%S'), r,c)) row.append(item) newRows.append(row) eTime = time.clock() - stTime outStr = 'Build %03f' % eTime format = '|%d/%b/%Y %H:%M:%S| ' stTime = time.clock() self.beginRemoveRows(QModelIndex(), 0, self.rowCount()) self.removeRows(0, self.rowCount()) self.endRemoveRows() eTime = time.clock() - stTime outStr += ', Remove %03f' % eTime stTime = time.clock() numNew = len(newRows) for r in range(numNew): self.appendRow(newRows[r]) eTime = time.clock() - stTime outStr += ', Set %03f' % eTime self.emit(SIGNAL('status'), outStr) self.reset() w = QWidget() w.setGeometry(200,200,800,600) hb = QVBoxLayout(w) tv = QTreeView() tvm = Model(tv) tv.setModel(tvm) sb = QStatusBar() reloader = Reloader_Thread() tvm.connect(tvm, SIGNAL('status'), sb.showMessage) reloader.connect(reloader, SIGNAL('refresh'), tvm.build) reloader.start() hb.addWidget(tv) hb.addWidget(sb) w.show() app.setStyle('plastique') app.processEvents(QEventLoop.AllEvents) app.aboutToQuit.connect(reloader.quit) app.exec_()

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  • Free solution for automatic updates with a .NET/C# app?

    - by a2h
    Yes, from searching I can see this has been asked time and time again. Here's a backstory. I'm an individual hobbyist developer with zero budget. A program I've been developing has been in need of constant bugfixes, and me and users are getting tired of having to manually update. Me, because my current solution of Manually FTP to my website Update a file "newest.txt" with the newest version Update index.html with a link to the newest version Hope for people to see the "there's an update" message Have them manually download the update sucks, and whenever I screw up an update, I get pitchforks. Users, because, well, "Are you ever going to implement auto-update?" "Will there ever be an auto-update feature?" Over the past I have looked into: WinSparkle - No in-app updates, and the DLL is 500 KB. My current solution is a few KBs in the executable and has no in-app updates. http://windowsclient.net/articles/appupdater.aspx - I can't comprehend the documentation http://www.codeproject.com/KB/vb/Auto_Update_Revisited.aspx - Doesn't appear to support anything other than working with files that aren't in use wyUpdate - wyBuild isn't free, and the file specification is simply too complex. Maybe if I was under a company paying me I could spend the time, but then I may as well pay for wyBuild. http://www.kineticjump.com/update/default.aspx - Ditto the last sentence. ClickOnce - Workarounds for implementing launching on startup are massive, horrendous and not worth it for such a simple feature. Publishing is a pain; manual FTP and replace of all files is required for servers without FrontPage Extensions. I'm pretty much ready to throw in the towel right now and strangle myself. And then I think about Sparkle... EDIT: I came across SparkleDotNET just then. Looks good, though the DLL is 200 KB. Don't know if that's really that big of an issue, though.

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