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• MVVM Binding Orthogonal Aspects in Views e.g. Application Settings

  - by chibacity

  I have an application which I am developing using WPF\Prism\MVVM. All is going well and I have some pleasing MVVM implementations. However, in some of my views I would like to be able to bind application settings e.g. when a user reloads an application, the checkbox for auto-scrolling a grid should be checked in the state it was last time the user used the application. My view needs to bind to something that holds the "auto-scroll" setting state. I could put this on the view-model, but applications settings are orthogonal to the purpose of the view-model. The "auto-scroll" setting is controlling an aspect of the view. This setting is just an example. There will be quite a number of them and splattering my view-models with properties to represent application settings (so I can bind them) feels decidedly yucky. One view-model per view seems to be de rigeuer... What is best\usual practice here? Splatter my view-models with application settings? Have multiple view-models per view so settings can be represented in their own right? Split views so that controls can bind to an ApplicationSettingsViewModel? = too many views? Something else? Edit 1 To add a little more context, I am developing a UI with a tabbed interface. Each tab will host a single widget and there a variety of widgets. Each widget is a Prism composition of individual views. Some views are common amongst widgets e.g. a file picker view. Whilst each widget is composed of several views, as a whole, conceptually a widget has a single set of user settings e.g. last file selected, auto-scroll enabled, etc. These need to be persisted and retrieved\applied when the application starts again, and the widget views are created. My question is focused on the fact that conceptually a widget has a single set of user settings which is at right-angles to the fact that a widget consists of many views. Each view in the widget has it's own view-model (which works nicely and logically) but if I stick to a one view-model per view, I would have to splatter each view-model with user settings appropriate to it. This doesn't sound right ?!?

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• Wordpress - related posts by custom taxonomy problem

  - by Nordin

  Hello, I'm trying to display related posts based on a custum taxonomy. I found a query at wordpress.org that kind of works. However the original post gets duplicated in the results multiple times. (words is the name of the custom taxonomy I use) What seems to happen is that the single post gets duplicated according to what amount showpost is set. Any idea's what could cause this? The code: <?php //for in the loop, display all "content", regardless of post_type, //that have the same custom taxonomy (e.g. words) terms as the current post $backup = $post; // backup the current object $found_none = '<h2>No related posts found!</h2>'; $taxonomy = 'words';// e.g. post_tag, category, custom taxonomy $param_type = 'words'; // e.g. tag__in, category__in, but genre__in will NOT work $post_types = get_post_types( array('public' => true), 'names' ); $tax_args=array('orderby' => 'none'); $tags = wp_get_post_terms( $post->ID , $taxonomy, $tax_args); if ($tags) { foreach ($tags as $tag) { $args=array( "$param_type" => $tag->slug, 'post__not_in' => array($post->ID), 'post_type' => $post_types, 'showposts'=>5, 'caller_get_posts'=>1 ); $my_query = null; $my_query = new WP_Query($args); if( $my_query->have_posts() ) { while ($my_query->have_posts()) : $my_query->the_post(); ?> <h3><a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title(); ?>"><?php the_title(); ?></a></h3> <?php $found_none = ''; endwhile; } } } if ($found_none) { echo $found_none; } $post = $backup; // copy it back wp_reset_query(); // to use the original query again ?>

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• Performance Optimization for Matrix Rotation

  - by Summer_More_More_Tea

  Hello everyone: I'm now trapped by a performance optimization lab in the book "Computer System from a Programmer's Perspective" described as following: In a N*N matrix M, where N is multiple of 32, the rotate operation can be represented as: Transpose: interchange elements M(i,j) and M(j,i) Exchange rows: Row i is exchanged with row N-1-i A example for matrix rotation(N is 3 instead of 32 for simplicity): ------- ------- |1|2|3| |3|6|9| ------- ------- |4|5|6| after rotate is |2|5|8| ------- ------- |7|8|9| |1|4|7| ------- ------- A naive implementation is: #define RIDX(i,j,n) ((i)*(n)+(j)) void naive_rotate(int dim, pixel *src, pixel *dst) { int i, j; for (i = 0; i < dim; i++) for (j = 0; j < dim; j++) dst[RIDX(dim-1-j, i, dim)] = src[RIDX(i, j, dim)]; } I come up with an idea by inner-loop-unroll. The result is: Code Version Speed Up original 1x unrolled by 2 1.33x unrolled by 4 1.33x unrolled by 8 1.55x unrolled by 16 1.67x unrolled by 32 1.61x I also get a code snippet from pastebin.com that seems can solve this problem: void rotate(int dim, pixel *src, pixel *dst) { int stride = 32; int count = dim >> 5; src += dim - 1; int a1 = count; do { int a2 = dim; do { int a3 = stride; do { *dst++ = *src; src += dim; } while(--a3); src -= dim * stride + 1; dst += dim - stride; } while(--a2); src += dim * (stride + 1); dst -= dim * dim - stride; } while(--a1); } After carefully read the code, I think main idea of this solution is treat 32 rows as a data zone, and perform the rotating operation respectively. Speed up of this version is 1.85x, overwhelming all the loop-unroll version. Here are the questions: In the inner-loop-unroll version, why does increment slow down if the unrolling factor increase, especially change the unrolling factor from 8 to 16, which does not effect the same when switch from 4 to 8? Does the result have some relationship with depth of the CPU pipeline? If the answer is yes, could the degrade of increment reflect pipeline length? What is the probable reason for the optimization of data-zone version? It seems that there is no too much essential difference from the original naive version. EDIT: My test environment is Intel Centrino Duo processor and the verion of gcc is 4.4 Any advice will be highly appreciated! Kind regards!

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• Complex Entity Framework linked-graphs issue: how to limit change set / break the graph?

  - by Hightechrider

  I have an EDMX containing Sentences, and Words, say and a Sentence contains three Words, say. Appropriate FK relationships exist between the tables. I create some words: Word word1 = new Word(); Word word2 = ... I build a Sentence: Sentence x = new Sentence (word1, word2, word3); I build another Sentence: Sentence y = new Sentence (word1, word4, word5); I try to save x to the database, but EF builds a change set that includes everything, including y, word4 and word5 that aren't ready to save to the database. When SaveChanges() happens it throws an exception: Unable to determine the principal end of the ... relationship. Multiple added entities may have the same primary key. I think it does this because Word has an EntityCollection<Sentence> on it from the FK relationship between the two tables, and thus Sentence y is inextricably linked to Sentence x through word1. So I remove the Navigation Property Sentences from Word and try again. It still tries to put the entire graph into the change set. What suggestions do the Entity Framework experts have for ways to break this connection. Essentially what I want is a one-way mapping from Sentence to Word; I don't want an EntityCollection<Sentence> on Word and I don't want the object graph to get intertwined like this. Code sample: This puts two sentences into the database because Verb1 links them and EF explores the entire graph of existing objects and added objects when you do Add/SaveChanges. Word subject1 = new Word(){ Text = "Subject1"}; Word subject2 = new Word(){ Text = "Subject2"}; Word verb1 = new Word(){ Text = "Verb11"}; Word object1 = new Word(){ Text = "Object1"}; Word object2 = new Word(){ Text = "Object2"}; Sentence s1 = new Sentence(){Subject = subject1, Verb=verb1, Object=object1}; Sentence s2 = new Sentence(){Subject=subject2, Verb=verb1, Object=object2}; context.AddToSentences(s1); context.SaveChanges(); foreach (var s in context.Sentences) { Console.WriteLine(s.Subject + " " + s.Verb + " " + s.Object); }

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• PostgreSQL - fetch the row which has the Max value for a column

  - by Joshua Berry

  I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id There are multiple users (distinct usr_id's) time_stamp is not a unique identifier: sometimes user events (one by row in the table) will occur with the same time_stamp. trans_id is unique only for very small time ranges: over time it repeats remaining_lives (for a given user) can both increase and decrease over time example: time_stamp|lives_remaining|usr_id|trans_id ----------------------------------------- 07:00 | 1 | 1 | 1 09:00 | 4 | 2 | 2 10:00 | 2 | 3 | 3 10:00 | 1 | 2 | 4 11:00 | 4 | 1 | 5 11:00 | 3 | 1 | 6 13:00 | 3 | 3 | 1 As I will need to access other columns of the row with the latest data for each given usr_id, I need a query that gives a result like this: time_stamp|lives_remaining|usr_id|trans_id ----------------------------------------- 11:00 | 3 | 1 | 6 10:00 | 1 | 2 | 4 13:00 | 3 | 3 | 1 As mentioned, each usr_id can gain or lose lives, and sometimes these timestamped events occur so close together that they have the same timestamp! Therefore this query won't work: SELECT b.time_stamp,b.lives_remaining,b.usr_id,b.trans_id FROM (SELECT usr_id, max(time_stamp) AS max_timestamp FROM lives GROUP BY usr_id ORDER BY usr_id) a JOIN lives b ON a.max_timestamp = b.time_stamp Instead, I need to use both time_stamp (first) and trans_id (second) to identify the correct row. I also then need to pass that information from the subquery to the main query that will provide the data for the other columns of the appropriate rows. This is the hacked up query that I've gotten to work: SELECT b.time_stamp,b.lives_remaining,b.usr_id,b.trans_id FROM (SELECT usr_id, max(time_stamp || '*' || trans_id) AS max_timestamp_transid FROM lives GROUP BY usr_id ORDER BY usr_id) a JOIN lives b ON a.max_timestamp_transid = b.time_stamp || '*' || b.trans_id ORDER BY b.usr_id Okay, so this works, but I don't like it. It requires a query within a query, a self join, and it seems to me that it could be much simpler by grabbing the row that MAX found to have the largest timestamp and trans_id. The table "lives" has tens of millions of rows to parse, so I'd like this query to be as fast and efficient as possible. I'm new to RDBM and Postgres in particular, so I know that I need to make effective use of the proper indexes. I'm a bit lost on how to optimize. I found a similar discussion here. Can I perform some type of Postgres equivalent to an Oracle analytic function? Any advice on accessing related column information used by an aggregate function (like MAX), creating indexes, and creating better queries would be much appreciated! P.S. You can use the following to create my example case: create TABLE lives (time_stamp timestamp, lives_remaining integer, usr_id integer, trans_id integer); insert into lives values ('2000-01-01 07:00', 1, 1, 1); insert into lives values ('2000-01-01 09:00', 4, 2, 2); insert into lives values ('2000-01-01 10:00', 2, 3, 3); insert into lives values ('2000-01-01 10:00', 1, 2, 4); insert into lives values ('2000-01-01 11:00', 4, 1, 5); insert into lives values ('2000-01-01 11:00', 3, 1, 6); insert into lives values ('2000-01-01 13:00', 3, 3, 1);

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• Programming graphics and sound on PC - Total newbie questions, and lots of them!

  - by Russel

  Hello, This isn't exactly specifically a programming question (or is it?) but I was wondering: How are graphics and sound processed from code and output by the PC? My guess for graphics: There is some reserved memory space somewhere that holds exactly enough room for a frame of graphics output for your monitor. IE: 800 x 600, 24 bit color mode == 800x600x3 = ~1.4MB memory space Between each refresh, the program writes video data to this space. This action is completed before the monitor refresh. Assume a simple 2D game: the graphics data is stored in machine code as many bytes representing color values. Depending on what the program(s) being run instruct the PC, the processor reads the appropriate data and writes it to the memory space. When it is time for the monitor to refresh, it reads from each memory space byte-for-byte and activates hardware depending on those values for each color element of each pixel. All of this of course happens crazy-fast, and repeats x times a second, x being the monitor's refresh rate. I've simplified my own likely-incorrect explanation by avoiding talk of double buffering, etc Here are my questions: a) How close is the above guess (the three steps)? b) How could one incorporate graphics in pure C++ code? I assume the practical thing that everyone does is use a graphics library (SDL, OpenGL, etc), but, for example, how do these libraries accomplish what they do? Would manual inclusion of graphics in pure C++ code (say, a 2D spite) involve creating a two-dimensional array of bit values (or three dimensional to include multiple RGB values per pixel)? Is this how it would be done waaay back in the day? c) Also, continuing from above, do libraries such as SDL etc that use bitmaps actual just build the bitmap/etc files into machine code of the executable and use them as though they were build in the same matter mentioned in question b above? d) In my hypothetical step 3 above, is there any registers involved? Like, could you write some byte value to some register to output a single color of one byte on the screen? Or is it purely dedicated memory space (=RAM) + hardware interaction? e) Finally, how is all of this done for sound? (I have no idea :) )

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• How Can I Populate Default Form Data with a ManyToMany Field?

  - by b14ck

  Ok, I've been crawling google and Django documentation for over 2 hours now (as well as the IRC channel on freenode), and haven't been able to figure this one out. Basically, I have a model called Room, which is displayed below: class Room(models.Model): """ A `Partyline` room. Rooms on the `Partyline`s are like mini-chatrooms. Each room has a variable amount of `Caller`s, and usually a moderator of some sort. Each `Partyline` has many rooms, and it is common for `Caller`s to join multiple rooms over the duration of their call. """ LIVE = 0 PRIVATE = 1 ONE_ON_ONE = 2 UNCENSORED = 3 BULLETIN_BOARD = 4 CHILL = 5 PHONE_BOOTH = 6 TYPE_CHOICES = ( ('LR', 'Live Room'), ('PR', 'Private Room'), ('UR', 'Uncensored Room'), ) type = models.CharField('Room Type', max_length=2, choices=TYPE_CHOICES) number = models.IntegerField('Room Number') partyline = models.ForeignKey(Partyline) owner = models.ForeignKey(User, blank=True, null=True) bans = models.ManyToManyField(Caller, blank=True, null=True) def __unicode__(self): return "%s - %s %d" % (self.partyline.name, self.type, self.number) I've also got a forms.py which has the following ModelForm to represent my Room model: from django.forms import ModelForm from partyline_portal.rooms.models import Room class RoomForm(ModelForm): class Meta: model = Room I'm creating a view which allows administrators to edit a given Room object. Here's my view (so far): def edit_room(request, id=None): """ Edit various attributes of a specific `Room`. Room owners do not have access to this page. They cannot edit the attributes of the `Room`(s) that they control. """ room = get_object_or_404(Room, id=id) if not room.is_owner(request.user): return HttpResponseForbidden('Forbidden.') if is_user_type(request.user, ['admin']): form_type = RoomForm elif is_user_type(request.user, ['lm']): form_type = LineManagerEditRoomForm elif is_user_type(request.user, ['lo']): form_type = LineOwnerEditRoomForm if request.method == 'POST': form = form_type(request.POST, instance=room) if form.is_valid(): if 'owner' in form.cleaned_data: room.owner = form.cleaned_data['owner'] room.save() else: defaults = {'type': room.type, 'number': room.number, 'partyline': room.partyline.id} if room.owner: defaults['owner'] = room.owner.id if room.bans: defaults['bans'] = room.bans.all() ### this does not work properly! form = form_type(defaults, instance=room) variables = RequestContext(request, {'form': form, 'room': room}) return render_to_response('portal/rooms/edit.html', variables) Now, this view works fine when I view the page. It shows all of the form attributes, and all of the default values are filled in (when users do a GET)... EXCEPT for the default values for the ManyToMany field 'bans'. Basically, if an admins clicks on a Room object to edit, the page they go to will show all of the Rooms default values except for the 'bans'. No matter what I do, I can't find a way to get Django to display the currently 'banned users' for the Room object. Here is the line of code that needs to be changed (from the view): defaults = {'type': room.type, 'number': room.number, 'partyline': room.partyline.id} if room.owner: defaults['owner'] = room.owner.id if room.bans: defaults['bans'] = room.bans.all() ### this does not work properly! There must be some other syntax I have to use to specify the default value for the 'bans' field. I've really been pulling my hair out on this one, and would definitely appreciate some help. Thanks!

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• Wondering about a way to conserve memory in C# using List<> with structs

  - by Michael Ryan

  I'm not even sure how I should phrase this question. I'm passing some CustomStruct objects as parameters to a class method, and storing them in a List. What I'm wondering is if it's possible and more efficient to add multiple references to a particular instance of a CustomStruct if a equivalent instance it found. This is a dummy/example struct: public struct CustomStruct { readonly int _x; readonly int _y; readonly int _w; readonly int _h; readonly Enum _e; } Using the below method, you can pass one, two, or three CustomStruct objects as parameters. In the final method (that takes three parameters), it may be the case that the 3rd and possibly the 2nd will have the same value as the first. List<CustomStruct> _list; public void AddBackground(CustomStruct normal) { AddBackground(normal, normal, normal); } public void AddBackground(CustomStruct normal, CustomStruct hover) { AddBackground(normal, hover, hover); } public void AddBackground(CustomStruct normal, CustomStruct hover, CustomStruct active) { _list = new List<CustomStruct>(3); _list.Add(normal); _list.Add(hover); _list.Add(active); } As the method stands now, I believe it will create new instances of CustomStruct objects, and then adds a reference of each to the List. It is my understanding that if I instead check for equality between normal and hover and (if equal) insert normal again in place of hover, when the method completes, hover will lose all references and eventually be garbage collected, whereas normal will have two references in the List. The same could be done for active. That would be better, right? The CustomStruct is a ValueType, and therefore one instance would remain on the Stack, and the three List references would just point to it. The overall List size is determined not by the object Type is contains, but by its Capacity. By eliminating the "duplicate" CustomStuct objects, you allow them to be cleaned up. When the CustomStruct objects are passed to these methods, new instances are created each time. When the structs are added to the List, is another copy made? For example, if i pass just one CustomStruct, AddBackground(normal) creates a copy of the original variable, and then passes it three times to Addbackground(normal, hover, active). In this method, three copies are made of the original copy. When the three local variables are added to the List using Add(), are additional copies created inside Add(), and does that defeat the purpose of any equality checks as previously mentioned? Am I missing anything here?

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• YASR - Yet another search and replace question

  - by petronius31

  Environment: asp.net c# openxml Ok, so I've been reading a ton of snippets and trying to recreate the wheel, but I'm hoping that somone can help me get to my desination faster. I have multiple documents that I need to merge together... check... I'm able to do that with openxml sdk. Birds are singing, sun is shining so far. Now that I have the document the way I want it, I need to search and replace text and/or content controls. I've tried using my own text - {replace this} but when I look at the xml (rename docx to zip and view the file), the { is nowhere near the text. So I either need to know how to protect that within the doucment so they don't diverge or I need to find another way to search and replace. I'm able to search/replace if it is an xml file, but then I'm back to not being able to combine the doucments easily. Code below... and as I mentioned... document merge works fine... just need to replace stuff. protected void exeProcessTheDoc(object sender, EventArgs e) { string doc1 = Server.MapPath("~/Templates/doc1.docx"); string doc2 = Server.MapPath("~/Templates/doc2.docx"); string final_doc = Server.MapPath("~/Templates/extFinal.docx"); File.Delete(final_doc); File.Copy(doc1, final_doc); using (WordprocessingDocument myDoc = WordprocessingDocument.Open(final_doc, true)) { string altChunkId = "AltChunkId2"; MainDocumentPart mainPart = myDoc.MainDocumentPart; AlternativeFormatImportPart chunk = mainPart.AddAlternativeFormatImportPart( AlternativeFormatImportPartType.WordprocessingML, altChunkId); using (FileStream fileStream = File.Open(doc2, FileMode.Open)) chunk.FeedData(fileStream); AltChunk altChunk = new AltChunk(); altChunk.Id = altChunkId; mainPart.Document.Body.InsertAfter(altChunk, mainPart.Document.Body.Elements<Paragraph>().Last()); mainPart.Document.Save(); } exeSearchReplace(final_doc); } protected void exeSearchReplace(string document) { using (WordprocessingDocument wordDoc = WordprocessingDocument.Open(document, true)) { string docText = null; using (StreamReader sr = new StreamReader(wordDoc.MainDocumentPart. GetStream())) { docText = sr.ReadToEnd(); } Regex regexText = new Regex("acvtClientName"); docText = regexText.Replace(docText, "Hi Everyone!"); using (StreamWriter sw = new StreamWriter(wordDoc.MainDocumentPart.GetStream(FileMode.Create))) { sw.Write(docText); } } } } }

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• select option in Safari ?

  - by Karandeep Singh

  < select size="2" multiple> < option value="1">1< /option> < option value="2">2< /option> < option value="3">3< /option> < option value="4">4< /option> < option value="5">5< /option> < option value="6">6< /option> < option value="7">7< /option> < option value="8">8< /option> < option value="9">9< /option> < option value="10">10< /option> < option value="11">11< /option> < option value="12">12< /option> < option value="13">13< /option> < /select> size attribute of Select tag is not working properly in Safari. if size attribute's value is greater than four then there have no problem, its working. But when I set the value of size less than four then it show four values. above example displays four options in safari but I want two options. What is the reason for this ?

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• What is a good platform for building a game framework targetting both web and native languages?

  - by fuzzyTew

  I would like to develop (or find, if one is already in development) a framework with support for accelerated graphics and sound built on a system flexible enough to compile to the following: native ppc/x86/x86_64/arm binaries or a language which compiles to them javascript actionscript bytecode or a language which compiles to it (actionscript 3, haxe) optionally java I imagine, for example, creating an API where I can open windows and make OpenGL-like calls and the framework maps this in a relatively efficient manner to either WebGL with a canvas object, 3d graphics in Flash, OpenGL ES 2 with EGL, or desktop OpenGL in an X11, Windows, or Cocoa window. I have so far looked into these avenues: Building the game library in haXe Pros: Targets exist for php, javascript, actionscript bytecode, c++ High level, object oriented language Cons: No support for finally{} blocks or destructors, making resource cleanup difficult C++ target does not allow room for producing highly optimized libraries -- the foreign function interface requires all primitive types be boxed in a wrapper object, as if writing bindings for a scripting language; these feel unideal for real-time graphics and audio, especially exporting low-level functions. Doesn't seem quite yet mature Using the C preprocessor to create a translator, writing programs entirely with macros Pros: CPP is widespread and simple to use Cons: This is an arduous task and probably the wrong tool for the job CPP implementations differ widely in support for features (e.g. xcode cpp has no variadic macros despite claiming C99 compliance) There is little-to-no room for optimization in this route Using llvm's support for multiple backends to target c/c++ to web languages Pros: Can code in c/c++ LLVM is a very mature highly optimizing compiler performing e.g. global inlining Targets exist for actionscript (alchemy) and javascript (emscripten) Cons: Actionscript target is closed source, unmaintained, and buggy. Javascript targets do not use features of HTML5 for appropriate optimization (e.g. linear memory with typed arrays) and are immature An LLVM target must convert from low-level bytecode, so high-level constructs are lost and bloated unreadable code is created from translating individual instructions, which may be more difficult for an unprepared JIT to optimize. "jump" instructions cause problems for languages with no "goto" statements. Using libclang to write a translator from C/C++ to web languages Pros: A beautiful parsing library providing easy access to the code structure Can code in C/C++ Has sponsored developer effort from Apple Cons: Incomplete; current feature set targets IDEs. Basic operators are unexposed and must be manually parsed from the returned AST element to be identified. Translating code prior to compilation may forgo optimizations assumed in c/c++ such as inlining. Creating new code generators for clang to translate into web languages Pros: Can code in C/C++ as libclang Cons: There is no API; code structure is unstable A much larger job than using libclang; the innards of clang are complex Building the game library in Common Lisp Pros: Flexible, ancient, well-developed language Extensive introspection should ease writing translators Translators exist for at least javascript Cons: Unfamiliar language No standardized library functions, widely varying implementations Which of these avenues should I pursue? Do you know of any others, or any systems that might be useful? Does a general project like this exist somewhere already? Thank you for any input.

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• Java getInputStreat SocketTimeoutException instead of NoRouteToHostException

  - by Jon

  I have an odd issue happening when trying to open multiple Input Streams (in separate threads) on Linux (RHEL). The behaviour works as expected on windows. I am kicking off 3 threads to open https connections to 3 different servers. All three are invalid IP addresses (in this test case), so I expect an NoRouteToHostException for each of them. The first two return these as expected, and quite quickly. (see stack trace below) However the third (and 4th when I tested it that way) do NOT give a no route exception. They wait for ages, and then give a SocketTimeoutException (see other stack trace below). This takes ages to come back, and does not accurately express the connection issue. The offending line of code is: reader = new BufferedReader(new InputStreamReader(conn.getInputStream())); Has anyone seen something like this before? Are there multi-threading issues with sockets on REHL or some limit somewhere to how many can connect at once...or...something? Expected stack trace, as received for first two: java.net.NoRouteToHostException: No route to host at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366) at java.net.Socket.connect(Socket.java:529) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:559) at sun.net.NetworkClient.doConnect(NetworkClient.java:158) at sun.net.www.http.HttpClient.openServer(HttpClient.java:394) at sun.net.www.http.HttpClient.openServer(HttpClient.java:529) at sun.net.www.protocol.https.HttpsClient.(HttpsClient.java:272) at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:329) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:172) at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:916) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:158) at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1177) at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234) Unexpected stack trace, as received on 3rd: java.net.SocketTimeoutException: connect timed out at java.net.PlainSocketImpl.socketConnect(Native Method) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366) at java.net.Socket.connect(Socket.java:529) at com.sun.net.ssl.internal.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:559) at sun.net.NetworkClient.doConnect(NetworkClient.java:158) at sun.net.www.http.HttpClient.openServer(HttpClient.java:394) at sun.net.www.http.HttpClient.openServer(HttpClient.java:529) at sun.net.www.protocol.https.HttpsClient.(HttpsClient.java:272) at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:329) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:172) at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:916) at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:158) at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1177) at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:234)

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• Using WSH (VBS) with iMacros - how do they do it?

  - by Carl

  (iMacros For Firefox 6.6.5.0; Firefox 3.6.3; Windows XP Pro SP3 w/all updates) I made an iMacro to select "load next 25" (comments) on a web page (CNN.COM). Unfortunately, iMacros doesn't appear to do looping (do the above until that string doesn't appear on the page anymore - i.e. all the comments are loaded). I tried putting {!iloop} in the TAG command, and it didn't work - then I read it wouldn't. So I tried the example at http://wiki.imacros.net/Loop_after_Query_or_Login I can't find any information on how to actually run the script in the above example. I searched Google and found VBS scripting is handled with .wsh files with Windows XP Pro. (The examples and other references there say Windows does VBS natively, so I looked up how with Google.) So I made the following .wsh file (modified the above example): Option Explicit Dim iim1, iret 'initialize iMacros instance set iim1 = CreateObject ("imacros") iret = iim1.iimInit() do while not iret < 0 iret = iim1.iimPlay("Load All CNN Comments") loop ' tell user we're done msgbox "End." ' exit iMacros instance and quit script iret = iim1.iimExit() Wscript.Quit() Here's the iMacro: (Load All CNN Comments.iim) VERSION BUILD=6650406 RECORDER=FX TAG POS=1 TYPE=A ATTR=TXT:Load<SP>next<SP>25 WAIT SECONDS=#DOWNLOADCOMPLETE# The iMacro works by itself - I press Play (left iMacro panel) and the next 25 comments load on the CNN.com page in the current tab. I put the .wsh file in the ...\iMacros\Macros directory - with the iMacro "Load All CNN Comments.iim" When I run the .wsh file (by just double clicking on it's icon - I created it with Notepad, and Windows gave it an icon for that file type - it's executable) I get the message from "Windows Script Host" - "There is no script file specified." I wasn't actually expecting it to work, as I don't see how Windows would know to call iMacros to run the iim macro. It would be nice if there was a simple, COMPLETE, example of how to use a VBS script with iMacros, that isn't bogged down with unnecessary complication like filling in a form, loading multiple pages, etc. I can't find ANY example. So what do I need to do to get this to work? I just installed iMacros yesterday, because I am constantly having the problem that there are hundred of comments after a CNN.com article, and loading 25 more at a time until they are all on the page makes it impractical to read any replies to my comments. It would also be nice if I could run the Macro from Firefox, rather than by double clicking on some file somewhere. Thanks for any help.

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• do I need to close an audio Clip?

  - by Michael

  have an application that processes real-time data and is supposed to beep when a certain event occurs. The triggering event can occur multiple times per second, and if the beep is already playing when another event triggers the code is just supposed to ignore it (as opposed to interrupting the current beep and starting a new one). Here is the basic code: Clip clickClip public void prepareProcess() { super.prepareProcess(); clickClip = null; try { clipFile = new File("C:/WINDOWS/Media/CHIMES.wav"); ais = AudioSystem.getAudioInputStream(clipFile); clickClip = AudioSystem.getClip(); clickClip.open(ais); fileIsLoaded = true; } catch (Exception ex) { clickClip = null; fileIsLoaded = false; } } public void playSound() { if (fileIsLoaded) { if ((clickClip==null) || (!clickClip.isRunning())) { try { clickClip.setFramePosition(0); clickClip.start(); } catch (Exception ex) { System.out.println("Cannot play click noise"); ex.printStackTrace(); } } } The prepareProcess method gets run once in the beginning, and the playSound method is called every time a triggering event occurs. My question is: do I need to close the clickClip object? I know I could add an actionListener to monitor for a Stop event, but since the event occurs so frequently I'm worried the extra processing is going to slow down the real-time data collection. The code seems to run fine, but my worry is memory leaks. The code above is based on an example I found while searching the net, but the example used an actionListener to close the Clip specifically "to eliminate memory leaks that would occur when the stop method wasn't implemented". My program is intended to run for hours so any memory leaks I have will cause problems. I'll be honest: I have no idea how to verify whether or not I've got a problem. I'm using Netbeans, and running the memory profiler just gave me a huge list of things that I don't know how to read. This is supposed to be the simple part of the program, and I'm spending hours on it. Any help would be greatly appreciated! Michael

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• Dynamic Objects for ASPxGridview

  - by André Snede Hansen

  I have a dictionary that is populated with data from a table, we are doing this so we can hold multiple SQL tables inside this object. This approached cannot be discussed. The Dictionary is mapped as a , and contains SQL column name and the value, and each dictionary resembles one row entry in the Table. Now I need to display this on a editable gridview, preferably the ASPxGridView. I already figured out that I should use Dynamic Objects(C#), and everything worked perfectly, up to the part where I find out that the ASPxGridview is built in .NET 2.0 and not 4.0 where Dynamic objects where implemented, therefor I cannot use it... As you cannot, to my knowledge, add rows to the gridview programmatically, I am out of ideas, and seek your help guys! protected void Page_Load(object sender, EventArgs e) { UserValidationTableDataProvider uvtDataprovider = _DALFactory.getProvider<UserValidationTableDataProvider>(typeof(UserValidationTableEntry)); string[] tableNames = uvtDataprovider.TableNames; UserValidationTableEntry[] entries = uvtDataprovider.getAllrecordsFromTable(tableNames[0]); userValidtionTableGridView.Columns.Clear(); Dictionary<string, string> firstEntry = entries[0].Values; foreach (KeyValuePair<string, string> kvp in firstEntry) { userValidtionTableGridView.Columns.Add(new GridViewDataColumn(kvp.Key)); } var dynamicObjectList = new List<dynamic>(); foreach (UserValidationTableEntry uvt in entries) { //dynamic dynObject = new MyDynamicObject(uvt.Values); dynamicObjectList.Add(new MyDynamicObject(uvt.Values)); } } public class MyDynamicObject : DynamicObject { Dictionary<string, string> properties = new Dictionary<string, string>(); public MyDynamicObject(Dictionary<string, string> dictio) { properties = dictio; } // If you try to get a value of a property // not defined in the class, this method is called. public override bool TryGetMember(GetMemberBinder binder, out object result) { // Converting the property name to lowercase // so that property names become case-insensitive. string name = binder.Name.ToLower(); string RResult; // If the property name is found in a dictionary, // set the result parameter to the property value and return true. // Otherwise, return false. bool wasSuccesfull = properties.TryGetValue(name, out RResult); result = RResult; return wasSuccesfull; } // If you try to set a value of a property that is // not defined in the class, this method is called. public override bool TrySetMember(SetMemberBinder binder, object value) { // Converting the property name to lowercase // so that property names become case-insensitive. properties[binder.Name.ToLower()] = value.ToString(); // You can always add a value to a dictionary, // so this method always returns true. return true; } } Now, I am almost certain that his "Dynamic object" approach, is not the one I can go with from here on. I hope you guys can help me :)!

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• How to catch 'exceptions' for out of order execution in Workflow Foundation 4?

  - by Alex Key

  Hi, I am attempting to model a worklfow using a "WCF Workflow Service" in .net / vs 2010 that needs to handle out of order execution gracefully (but not allow it - if thath makes sense!?) For example I have 2 receive activities one called Initialize and the other called GetValue inside a FlowChart. In most cases Initialize should be called first and GetValue after (as modled in the flow chart). However if GetValue is executed before Initialize I do not want to return an "out of order" exception (although when I look at the WCF test client, I can't actually see an exception). But instead a custom exception saying something like "you must initialize first". In theory I could model this with lots of parallel activities and conditions to check if Initialized / Running / Terminated etc. But the business process I am modelling if very very similar to a state machine... except it must handle people executing things in the wrong order. Ideally I would like to catch the "out of order" exception (thought I don't think it's really an exception as such), check the 'exception' to see which function was attempted to run and then handle it. I have done some research around enabling AllowBufferedReceive. However I don't want to be able to execute out of order (I don't think), but instead give a detailed response if it does happen. I've looked at the new beta state machine template for WF 4 - but i'm not sure if it does what i'm after? I'm not sure if I have the wrong end of the stick, so any help would be greatly appreciated. [EDIT] To help clarify... Sorry it's a tricky one to explain. The standard I am trying to implement (the e-learning standard SCORM RTE) is structured like a state machine i.e. certain functions can only be executed in certain states. However the standard specifies that if the calling clients tries to execute a function that it is not meant to, then a warning should be issued... for example "you cannot use GetValue(), because you have not yet Initialized". Ideally I'd like to structure the workflow as the theoretical state machine and not need to have to use multiple if/else's to handle all the scenarios where something could be executed out-of-order. I'd like to catch a out-of-order exception (but I don't think there is such an exception - as it's not in the debugger) and rethrow it.

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• How do I correct "Commit Failed. File xxx is out of date. xxx path not found."

  - by Ryan Taylor

  I have recently run into a particularly sticky issue regarding committing the result of a merge in subversion. Our Subversion server is @ 1.5.0 and my TortoiseSVN client is now @ 1.6.1. I am trying to merge a feature branch back into my trunk. The merge appears to work okay; however, the commit fails with the following error message. Commit failed (details follow): File 'flex/src/com/penbay/invision/portal/services/http/soap/ReportServices/GetAllBldgsParamsByRegionBySiteResultEvent.as' is out of date '/svn/ibis/!svn/wrk/531d459d-80fa-ea46-bfb4-940d79ee6d2e/visualization/trunk/source/flex/src/com/penbay/invision/portal/services/http/soap/ReportServices/GetAllBldgsParamsByRegionBySiteResultEvent.as' path not found You have to update your working copy first. My working trunk is up to date. I have even checked out a new one into a different folder to make sure there wasn't any local cruft messing with the merge. I have done some more research into this and I think part of the problem is user error. I think our problems are: We had some developers committing work with a subversion client before 1.5 and some after. I believe this has the potential to corrupt the merge info. In other branches we have performed partial merges. That is, we did not always perform merges at the root of the branch. This was to facilitate updating Flex and .NET efforts within the same branch. We performed cyclic (reflexive) merges on our branch. This was done because we had multiple parallel branches and we wanted to periodically update our branch with the latest code in trunk. All of these things are explicitly not recommended by the Subversion book/team. We have learned our lesson and now know the best practices. However, we first need to merge and commit our latest branch. What it the best way to correct the problems we are encountering? Would deleting all the merge info in the trunk and branch be a viable solution? No. I have done this but it does not resolve the error that I am getting above.

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• Synchronizing thread communication?

  - by Roger Alsing

  Just for the heck of it I'm trying to emulate how JRuby generators work using threads in C#. Also, I'm fully aware that C# haas built in support for yield return, I'm just toying around a bit. I guess it's some sort of poor mans coroutines by keeping multiple callstacks alive using threads. (even though none of the callstacks should execute at the same time) The idea is like this: The consumer thread requests a value The worker thread provides a value and yields back to the consumer thread Repeat untill worker thread is done So, what would be the correct way of doing the following? //example class Program { static void Main(string[] args) { ThreadedEnumerator<string> enumerator = new ThreadedEnumerator<string>(); enumerator.Init(() => { for (int i = 1; i < 100; i++) { enumerator.Yield(i.ToString()); } }); foreach (var item in enumerator) { Console.WriteLine(item); }; Console.ReadLine(); } } //naive threaded enumerator public class ThreadedEnumerator<T> : IEnumerator<T>, IEnumerable<T> { private Thread enumeratorThread; private T current; private bool hasMore = true; private bool isStarted = false; AutoResetEvent enumeratorEvent = new AutoResetEvent(false); AutoResetEvent consumerEvent = new AutoResetEvent(false); public void Yield(T item) { //wait for consumer to request a value consumerEvent.WaitOne(); //assign the value current = item; //signal that we have yielded the requested enumeratorEvent.Set(); } public void Init(Action userAction) { Action WrappedAction = () => { userAction(); consumerEvent.WaitOne(); enumeratorEvent.Set(); hasMore = false; }; ThreadStart ts = new ThreadStart(WrappedAction); enumeratorThread = new Thread(ts); enumeratorThread.IsBackground = true; isStarted = false; } public T Current { get { return current; } } public void Dispose() { enumeratorThread.Abort(); } object System.Collections.IEnumerator.Current { get { return Current; } } public bool MoveNext() { if (!isStarted) { isStarted = true; enumeratorThread.Start(); } //signal that we are ready to receive a value consumerEvent.Set(); //wait for the enumerator to yield enumeratorEvent.WaitOne(); return hasMore; } public void Reset() { throw new NotImplementedException(); } public IEnumerator<T> GetEnumerator() { return this; } System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { return this; } } Ideas?

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• Dynamic data-entry value store

  - by simendsjo

  I'm creating a data-entry application where users are allowed to create the entry schema. My first version of this just created a single table per entry schema with each entry spanning a single or multiple columns (for complex types) with the appropriate data type. This allowed for "fast" querying (on small datasets as I didn't index all columns) and simple synchronization where the data-entry was distributed on several databases. I'm not quite happy with this solution though; the only positive thing is the simplicity... I can only store a fixed number of columns. I need to create indexes on all columns. I need to recreate the table on schema changes. Some of my key design criterias are: Very fast querying (Using a simple domain specific query language) Writes doesn't have to be fast Many concurrent users Schemas will change often Schemas might contain many thousand columns The data-entries might be distributed and needs syncronization. Preferable MySQL and SQLite - Databases like DB2 and Oracle is out of the question. Using .Net/Mono I've been thinking of a couple of possible designs, but none of them seems like a good choice. Solution 1: Union like table containing a Type column and one nullable column per type. This avoids joins, but will definitly use a lot of space. Solution 2: Key/value store. All values are stored as string and converted when needed. Also use a lot of space, and of course, I hate having to convert everything to string. Solution 3: Use an xml database or store values as xml. Without any experience I would think this is quite slow (at least for the relational model unless there is some very good xpath support). I also would like to avoid an xml database as other parts of the application fits better as a relational model, and being able to join the data is helpful. I cannot help to think that someone has solved (some of) this already, but I'm unable to find anything. Not quite sure what to search for either... I know market research is doing something like this for their questionnaires, but there are few open source implementations, and the ones I've found doesn't quite fit the bill. PSPP has much of the logic I'm thinking of; primitive column types, many columns, many rows, fast querying and merging. Too bad it doesn't work against a database.. And of course... I don't need 99% of the provided functionality, but a lot of stuff not included. I'm not sure this is the right place to ask such a design related question, but I hope someone here has some tips, know of any existing work, or can point me to a better place to ask such a question. Thanks in advance!

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• Associated models in Rails?

  - by dannymcc

  Hi Everyone, In my rails application I have two models called Kases and Notes. They work in the same way comments do with blog posts, I.e. each Kase entry can have multiple notes attached to it. I have got everything working, but for some reason I cannot get the destroy link to work for the Notes. I think I am overlooking something that is different with associated models to standard models. Notes Controller class NotesController < ApplicationController # POST /notes # POST /notes.xml def create @kase = Kase.find(params[:kase_id]) @note = @kase.notes.create!(params[:note]) respond_to do |format| format.html { redirect_to @kase } format.js end end end Kase Model class Kase < ActiveRecord::Base validates_presence_of :jobno has_many :notes Note Model class Note < ActiveRecord::Base belongs_to :kase end In the Kase show view I call a partial within /notes called _notes.html.erb: Kase Show View <div id="notes"> <h2>Notes</h2> <%= render :partial => @kase.notes %> <% form_for [@kase, Note.new] do |f| %> <p> <h3>Add a new note</h3> <%= f.text_field :body %><%= f.submit "Add Note" %> </p> <% end %> </div> /notes/_note.html.erb <% div_for note do %> <div id="sub-notes"> <p> <%= h(note.body) %><br /> <span style="font-size:smaller">Created <%= time_ago_in_words(note.created_at) %> ago on <%= note.created_at %></span> </p> <%= link_to "Remove Note", kase_path(@kase), :confirm => 'Are you sure?', :method => :delete, :class => 'important' %> </div> <% end %> As you can see, I have a Remove Note destroy link, but that destroys the entire Kase the note is associated with. How do I make the destroy link remove only the note? <%= link_to "Remove Note", kase_path(@kase), :confirm => 'Are you sure?', :method => :delete, :class => 'important' %> Any help would, as always, be greatly appreciated! Thanks, Danny

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• CSS3's border-radius property and border-collapse:collapse don't mix. How can I use border-radius to

  - by vamin

  Edit - Original Title: Is there an alternative way to achieve border-collapse:collapse in CSS (in order to have a collapsed, rounded corner table)? Since it turns out that simply getting the table's borders to collapse does not solve the root problem, I have updated the title to better reflect the discussion. I am trying to make a table with rounded corners using the CSS3 border-radius property. The table styles I'm using look something like this: table { -moz-border-radius:10px; -webkit-border-radius:10px; border-radius:10px} Here's the problem. I also want to set the border-collapse:collapse property, and when that is set border-radius no longer works (at least in Firefox)(edit- I thought this might just be a difference in mozilla's implementation, but it turns out this is the way it's supposed to work according to the w3c). Is there a CSS-based way I can get the same effect as border-collapse:collapse without actually using it? Edits: I've made a simple page to demonstrate the problem here (Firefox/Safari only). It seems that a large part of the problem is that setting the table to have rounded corners does not affect the corners of the corner td elements. If the table was all one color, this wouldn't be a problem since I could just make the top and bottom td corners rounded for the first and last row respectively. However, I am using different background colors for the table to differentiate the headings and for striping, so the inner td elements would show their rounded corners as well. Summary of proposed solutions: Surrounding the table with another element with round corners doesn't work because the table's square corners "bleed through." Specifying border width to 0 doesn't collapse the table. Bottom td corners still square after setting cellspacing to zero. Using javascript instead- works by avoiding the problem. Possible solutions: The tables are generated in php, so I could just apply a different class to each of the outer th/tds and style each corner separately. I'd rather not do this, since it's not very elegant and a bit of a pain to apply to multiple tables, so please keep suggestions coming. Possible solution 2 is to use javascript (jQuery, specifically) to style the corners. This solution also works, but still not quite what I'm looking for (I know I'm picky). I have two reservations: 1) this is a very lightweight site, and I'd like to keep javascript to the barest minimum 2) part of the appeal that using border-radius has for me is graceful degradation and progressive enhancement. By using border-radius for all rounded corners, I hope to have a consistently rounded site in CSS3-capable browsers and a consistently square site in others (I'm looking at you, IE). I know that trying to do this with CSS3 today may seem needless, but I have my reasons. I would also like to point out that this problem is a result of the w3c speficication, not poor CSS3 support, so any solution will still be relevant and useful when CSS3 has more widespread support.

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• Editing/Updating one of the results in a search query.

  - by eggman20

  Hi guys. I'm creating a page that searches for an item and then be able to edit/update it. I was able to do it when it returns just one result but when it gives me multiple results I could only edit the very last item. Below is my code: ....... $dj =$_POST[djnum]; $sql= "SELECT * From dj WHERE datajack LIKE '$dj%'"; $result = mysql_query($sql); //more code in here// while ($info =mysql_fetch_array($result)) { // display the result echo "<form action=\"dj_update.php\" method=\"POST\"><input type=\"hidden\" name=\"djnumber\" value=\"".$info['datajack']."\">"; echo "<tr><td>DJ ".$info['datajack']."</td>"; echo "<td>".$info['building']."&nbsp;</td>"; echo "<td>Rm ".$info['room']."&nbsp;</td>"; echo "<td>".$info['switch']."&nbsp;</td>"; echo "<td>".$info['port']."&nbsp;</td>"; echo "<td>".$info['notes']."&nbsp;</td>"; echo "<td style=\"text-align:center;\"><input type=\"Submit\" value=\"Edit\" ></td></tr>"; } // more code here // Then this is the screen shot of the result: The idea is the user should be able to click on "Edit" and be able to edit/update that particular item. But when I click any of the Edit button I could only edit the last item. What am I missing here? Is there an easier way to do this? Thanks guys and Happy new year!

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• Closure Tables - Is this enough data to display a tree view?

  - by James Pitt

  Here is the table I have created by testing the closure table method. | id | parentId | childId | hops | | | | | 270 | 6 | 6 | 0 | 271 | 7 | 7 | 0 | 272 | 8 | 8 | 0 | 273 | 9 | 9 | 0 | 276 | 10 | 10 | 0 | 281 | 9 | 10 | 1 | 282 | 7 | 9 | 1 | 283 | 7 | 10 | 2 | 285 | 7 | 8 | 1 | 286 | 6 | 7 | 1 | 287 | 6 | 9 | 2 | 288 | 6 | 10 | 3 | 289 | 6 | 8 | 2 | 293 | 6 | 9 | 1 | 294 | 6 | 10 | 2 I am trying to create a simple tree of this using PHP. There does not seem to be enough data to create the table. For example, when I look purely at parentId = 6: -Part 6 -Part 7 - ? - ? -Part 9 - ? - ? We know that parts 8 and 10 exists below Part 7 or 9, but not which. We know that part 10 exists at both 3 and 4 nodes deep but where? If I look at other data in the table it is possible to tell it should be: - Part 6 - Part 7 - Part 9 - Part 10 - Part 9 - Part 10 I thought one of the benefits of closure tables was there was no need for recursive queries? Could you help explain what I am doing wrong? EDIT: For clarification, this is a mapping table. There is another table called "parts" which has a column called part_id that correlates to both the parentId and childId columns in the "closure" table. The "id" column in the table above (closure) is just for the purposes of maintaining a primary key. It is not really necessary. The methods I have used to create this closure table is described in the following article: http://dirtsimple.org/2010/11/simplest-way-to-do-tree-based-queries.html EDIT2: It can have two and three hops. I will explain easier by assigning names to the items. Part 6 = Bicycle Part 7 = Gears Part 8 = Chain Part 9 = Bolt Part 10 = Nut Nut is part of Bolt. The Bolt and Nut combo exists directly within Bicycle and within Gears which is part of Bicycle. In relation to what method to use I have looked at Adjacency, Edges, Enum Paths, Closures, DAGS(networks) and the Nested Set Model. I am still trying to work out what is what, but this is an extremely complex component database where there are multiple parents and any modification to a sub-tree must propogate through the other trees. More importantly there will be insertions, deletions and tree views that I wish to avoid recursion during general use, even at the cost of database space and query time during entry.

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• JSON.Net: deserializing polymorphic types without specifying the assembly

  - by Frank Schwieterman

  I see that using JSON.Net, I can decode polymorphic objects if a $type attribute specifies the specific type of the JSON object. In all the examples I've seen, $type includes the namespace. Is it possible to make this work including just a simple typename without the assembly? I'd be happy to specify a default assembly to the JsonSerializer if thats possible I am able to deserialize the JSON using: public class SingleAssemblyJsonTypeBinder : SerializationBinder { private readonly Assembly _assembly; private Dictionary _typesBySimpleName = new Dictionary(StringComparer.OrdinalIgnoreCase); private Dictionary _simpleNameByType = new Dictionary(); public SingleAssemblyJsonTypeBinder(Assembly assembly) { _assembly = assembly; _typesBySimpleName = new Dictionary<string, Type>(); foreach (var type in _assembly.GetTypes().Where(t => t.IsPublic)) { if (_typesBySimpleName.ContainsKey(type.Name)) throw new InvalidOperationException("Cannot user PolymorphicBinder on a namespace where multiple public types have same name."); _typesBySimpleName[type.Name] = type; _simpleNameByType[type] = type.Name; } } public override Type BindToType(string assemblyName, string typeName) { Type result; if (_typesBySimpleName.TryGetValue(typeName.Trim(), out result)) return result; return null; } public override void BindToName(Type serializedType, out string assemblyName, out string typeName) { string name; if (_simpleNameByType.TryGetValue(serializedType, out name)) { typeName = name; assemblyName = null;// _assembly.FullName; } else { typeName = null; assemblyName = null; } } } ... public static JsonSerializerSettings GetJsonSerializationSettings() { var settings = new JsonSerializerSettings(); settings.Binder = new SingleAssemblyJsonTypeBinder(typeof(MvcApplication).Assembly); settings.TypeNameHandling = TypeNameHandling.Objects; return settings; } .... var serializer = JsonSerializer.Create(settings); I haven't been able to make this work with MVC though, I'm configuring json deserialization per the code below in Application_Start, and the object is deserialized, but using the base type one. GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.Binder = new SingleAssemblyJsonTypeBinder(this.GetType().Assembly); GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.TypeNameHandling = TypeNameHandling.All; GlobalConfiguration.Configuration.Formatters.JsonFormatter.SerializerSettings.TypeNameAssemblyFormat = FormatterAssemblyStyle.Simple;

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• IF Statement has strange behavior

  - by BSchlinker

  I've developed a 'custom' cout, so that I can display text to console and also print it to a log file. This cout class is passed a different integer on initialization, with the integer representing the verbosity level of the message. If the current verbosity level is greater then or equal to the verbosity level of the message, the message should print. The problem is, I have messages printing even when the current verbosity level is too low. I went ahead and debugged it, expecting to find the problem. Instead, I found multiple scenarios where my if statements are not working as expected. The statement if(ilralevel_passed <= ilralevel_set) will sometimes proceed even if ilralevel_set is LESS then ilralevel_passed. You can see this behavior in the following picture (my apologizes for using Twitpic) http://twitpic.com/1xtx4g/full. Notice how ilralevel_set is equal to zero, and ilralevel_passed is equal to one. Yet, the if statement has returned true and is now moving forward to pass the line to cout. I've never seen this type of behavior before and I'm not exactly sure how to proceed debugging it. I'm not able to isolate the behavior either -- it only occurs in certain parts of my program. Any suggestions are appreciated as always. // Here is an example use of the function: // ilra_status << setfill('0') << setw(2) << dispatchtime.tm_sec << endl; // ilra_warning << "Dispatch time (seconds): " << mktime(&dispatchtime) << endl; // Here is the 'custom' cout function: #ifndef ILRA_H_ #define ILRA_H_ // System libraries #include <iostream> #include <ostream> #include <sstream> #include <iomanip> // Definitions #define ilra_talk ilra(__FUNCTION__,0) #define ilra_update ilra(__FUNCTION__,0) #define ilra_error ilra(__FUNCTION__,1) #define ilra_warning ilra(__FUNCTION__,2) #define ilra_status ilra(__FUNCTION__,3) // Statics static int ilralevel_set = 0; static int ilralevel_passed; // Classes class ilra { public: // constructor / destructor ilra(const std::string &funcName, int toset) { ilralevel_passed = toset; } ~ilra(){}; // enable / disable irla functions static void ilra_verbose_level(int toset){ ilralevel_set = toset; } // output template <class T> ilra &operator<<(const T &v) { if(ilralevel_passed <= ilralevel_set) std::cout << v; return *this; } ilra &operator<<(std::ostream&(*f)(std::ostream&)) { if(ilralevel_passed <= ilralevel_set) std::cout << *f; return *this; } }; // end of the class #endif /* ILRA_H_ */

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