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  • How to clean and simplify this code?

    - by alkalim
    After thinking about This Question and giving an answer to it I wanted to do more about that to train myself. So I wrote a function which will calc the length of an given function. Th given php-file has to start at the beginning of the needed function. Example: If the function is in a big phpfile with lots of functions, like /* lots of functions */ function f_interesting($arg) { /* function */ } /* lots of other functions */ then $part3 of my function will require to begin like that (after the starting-{ of the interesting function): /* function */ } /* lots of other functions */ Now that's not the problem, but I would like to know if there are an cleaner or simplier ways to do this. Here's my function: (I already cleaned a lot of testing-echo-commands) (The idea behind it is explained here) function f_analysis ($part3) { if(isset($part3)) { $char_array = str_split($part3); //get array of chars $end_key = false; //length of function $depth = 0; //How much of unclosed '{' $in_sstr = false; //is next char inside in ''-String? $in_dstr = false; //is nect char inside an ""-String? $in_sl_comment = false; //inside an //-comment? $in_ml_comment = false; //inside an /* */-comment? $may_comment = false; //was the last char an '/' which can start a comment? $may_ml_comment_end = false; //was the last char an '*' which may end a /**/-comment? foreach($char_array as $key=>$char) { if($in_sstr) { if ($char == "'") { $in_sstr = false; } } else if($in_dstr) { if($char == '"') { $in_dstr = false; } } else if($in_sl_comment) { if($char == "\n") { $in_sl_comment = false; } } else if($in_ml_comment) { if($may_ml_comment_end) { $may_ml_comment_end = false; if($char == '/') { $in_ml_comment = false; } } if($char == '*') { $may_ml_comment_end = true; } } else if ($may_comment) { if($char == '/') { $in_sl_comment = true; } else if($char == '*') { $in_ml_comment = true; } $may_comment = false; } else { switch ($char) { case '{': $depth++; break; case '}': $depth--; break; case '/': $may_comment = true; break; case '"': $in_dstr = true; break; case "'": $in_sstr = true; break; } } if($depth < 0) { $last_key = $key; break; } } } else echo '<br>$part3 of f_analysis not set!'; return ($last_key===false) ? false : $last_key+1; //will be false or the length of the function }

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  • WPF Binding when setting DataTemplate Programically

    - by Daniel
    Hello, I have my little designer tool (my program). On the left side I have TreeView and on the right site I have Accordion. When I select a node I want to dynamically build Accordion Items based on Properties from DataContext of selected node. Selecting nodes works fine, and when I use this sample code for testing it works also. XAML code: <layoutToolkit:Accordion x:Name="accPanel" SelectionMode="ZeroOrMore" SelectionSequence="Simultaneous"> <layoutToolkit:AccordionItem Header="Controller Info"> <StackPanel Orientation="Horizontal" DataContext="{Binding}"> <TextBlock Text="Content:" /> <TextBlock Text="{Binding Path=Name}" /> </StackPanel> </layoutToolkit:AccordionItem> </layoutToolkit:Accordion> C# code: private void treeSceneNode_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e) { if (e.NewValue != e.OldValue) { if (e.NewValue is SceneNode) { accPanel.DataContext = e.NewValue; //e.NewValue is a class that contains Name property } } } But the problem occurs when I'm trying to achive this using DateTemplate and dynamically build AccordingItem, the Binding is not working: <layoutToolkit:Accordion x:Name="accPanel" SelectionMode="ZeroOrMore" SelectionSequence="Simultaneous"> </layoutToolkit:Accordion> and DateTemplate in my ResourceDictionary <DataTemplate x:Key="dtSceneNodeContent"> <StackPanel Orientation="Horizontal" DataContext="{Binding}"> <TextBlock Text="Content:" /> <TextBlock Text="{Binding Path=Name}" /> </StackPanel> </DataTemplate> and C# code: private void treeSceneNode_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e) { if (e.NewValue != e.OldValue) { ResourceDictionary rd = new ResourceDictionary(); rd.Source = new Uri("/SilverGL.GUI;component/SilverGLDesignerResourceDictionary.xaml", UriKind.RelativeOrAbsolute); if (e.NewValue is SceneNode) { accPanel.DataContext = e.NewValue; AccordionItem accController = new AccordionItem(); accController.Header = "Controller Info"; accController.ContentTemplate = rd["dtSceneNodeContent"] as DataTemplate; accPanel.Items.Add(accController); } else { // Other type of node } } } I really need help with this issue. Thanks for any support. Daniel

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  • Java app makes screen display unresponsive after 10 minutes of user idle time

    - by Ross
    I've written a Java app that allows users to script mouse/keyboard input (JMacro, link not important, only for the curious). I personally use the application to automate character actions in an online game overnight while I sleep. Unfortunately, I keep coming back to the computer in the morning to find it unresponsive. Upon further testing, I'm finding that my application causes the computer to become unresponsive after about 10 minutes of user idle time (even if the application itself it simulating user activity). I can't seem to pin-point the issue, so I'm hoping somebody else might have a suggestion of where to look or what might be causing the issue. The relevant symptoms and characteristics: Unresponsiveness occurs after user is idle for 10 minutes User can still move the mouse pointer around the screen Everything but the mouse appears frozen... mouse clicks have no effect and no applications update their displays, including the Windows 7 desktop I left the task manager up along the with the app overnight so I could see the last task manager image before the screen freezes... the Java app is at normal CPU/Memory usage and total CPU usage is only ~1% After moving the mouse (in other words, the user comes back from being idle), the screen image starts updating again within 30 minutes (this is very hit and miss... sometimes 10 minutes, sometimes no results after two hours) User can CTRL-ALT-DEL to get to Windows 7's CTRL-ALT-DEL screen (after a 30 second pause). User is still able to move mouse pointer, but clicking any of the button options causes the screen to appear to freeze again On some very rare occasions, the system never freezes, and I come back to it in the morning with full responsiveness The Java app automatically stops input scripting in the middle of the night, so Windows 7 detects "real" idleness and turns the monitors into Standby mode... which they successfully come out of upon manually moving the mouse in the morning when I wake up, even though the desktop display still appears frozen Given the symptoms and characteristics of the issue, it's as if the Java app is causing the desktop display of the logged in user to stop updating, including any running applications. Programming concepts and Java packages used: Multi-threading Standard out and err are rerouted to a javax.swing.JTextArea The application uses a Swing GUI awt.Robot (very heavily used) awt.PointerInfo awt.MouseInfo System Specs: Windows 7 Professional Java 1.6.0 u17 In conclusion, I should stress that I'm not looking for any specific solutions, as I'm not asking a very specific question. I'm just wondering if anybody has run into a similar problem when using the Java libraries that I'm using. I would also gladly appreciate any suggestions for things to try to attempt to further pinpoint what is causing my problem. Thanks! Ross PS, I'll post an update/answer if I manage to stumble across anything else while I continue to debug this.

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  • Objective-c design advice for use of different data sources, swapping between test and live

    - by user200341
    I'm in the process of designing an application that is part of a larger piece of work, depending on other people to build an API that the app can make use of to retrieve data. While I was thinking about how to setup this project and design the architecture around it, something occurred to me, and I'm sure many people have been in similar situations. Since my work is depending on other people to complete their tasks, and a test server, this slows work down at my end. So the question is: What's the best practice for creating test repositories and classes, implementing them, and not having to depend on altering several places in the code to swap between the test classes and the actual repositories / proper api calls. Contemplate the following scenario: GetDataFromApiCommand *getDataCommand = [[GetDataFromApiCommand alloc]init]; getDataCommand.delegate = self; [getDataCommand getData]; Once the data is available via the API, "GetDataFromApiCommand" could use the actual API, but until then a set of mock data could be returned upon the call of [getDataCommand getData] There might be multiple instances of this, in various places in the code, so replacing all of them wherever they are, is a slow and painful process which inevitably leads to one or two being overlooked. In strongly typed languages we could use dependency injection and just alter one place. In objective-c a factory pattern could be implemented, but is that the best route to go for this? GetDataFromApiCommand *getDataCommand = [GetDataFromApiCommandFactory buildGetDataFromApiCommand]; getDataCommand.delegate = self; [getDataCommand getData]; What is the best practices to achieve this result? Since this would be most useful, even if you have the actual API available, to run tests, or work off-line, the ApiCommands would not necessarily have to be replaced permanently, but the option to select "Do I want to use TestApiCommand or ApiCommand". It is more interesting to have the option to switch between: All commands are test and All command use the live API, rather than selecting them one by one, however that would also be useful to do for testing one or two actual API commands, mixing them with test data. EDIT The way I have chosen to go with this is to use the factory pattern. I set up the factory as follows: @implementation ApiCommandFactory + (ApiCommand *)newApiCommand { // return [[ApiCommand alloc]init]; return [[ApiCommandMock alloc]init]; } @end And anywhere I want to use the ApiCommand class: GetDataFromApiCommand *getDataCommand = [ApiCommandFactory newApiCommand]; When the actual API call is required, the comments can be removed and the mock can be commented out. Using new in the message name implies that who ever uses the factory to get an object, is responsible for releasing it (since we want to avoid autorelease on the iPhone). If additional parameters are required, the factory needs to take these into consideration i.e: [ApiCommandFactory newSecondApiCommand:@"param1"]; This will work quite well with repositories as well.

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  • Reading and writing C++ vector to a file

    - by JB
    For some graphics work I need to read in a large amount of data as quickly as possible and would ideally like to directly read and write the data structures to disk. Basically I have a load of 3d models in various file formats which take too long to load so I want to write them out in their "prepared" format as a cache that will load much faster on subsequent runs of the program. Is it safe to do it like this? My worries are around directly reading into the data of the vector? I've removed error checking, hard coded 4 as the size of the int and so on so that i can give a short working example, I know it's bad code, my question really is if it is safe in c++ to read a whole array of structures directly into a vector like this? I believe it to be so, but c++ has so many traps and undefined behavour when you start going low level and dealing directly with raw memory like this. I realise that number formats and sizes may change across platforms and compilers but this will only even be read and written by the same compiler program to cache data that may be needed on a later run of the same program. #include <fstream> #include <vector> using namespace std; struct Vertex { float x, y, z; }; typedef vector<Vertex> VertexList; int main() { // Create a list for testing VertexList list; Vertex v1 = {1.0f, 2.0f, 3.0f}; list.push_back(v1); Vertex v2 = {2.0f, 100.0f, 3.0f}; list.push_back(v2); Vertex v3 = {3.0f, 200.0f, 3.0f}; list.push_back(v3); Vertex v4 = {4.0f, 300.0f, 3.0f}; list.push_back(v4); // Write out a list to a disk file ofstream os ("data.dat", ios::binary); int size1 = list.size(); os.write((const char*)&size1, 4); os.write((const char*)&list[0], size1 * sizeof(Vertex)); os.close(); // Read it back in VertexList list2; ifstream is("data.dat", ios::binary); int size2; is.read((char*)&size2, 4); list2.resize(size2); // Is it safe to read a whole array of structures directly into the vector? is.read((char*)&list2[0], size2 * sizeof(Vertex)); }

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  • Parsing XML data with Namespaces in PHP

    - by osbmedia
    I'm trying to work with this XML feed that uses namespaces and i'm not able to get past the colon in the tags. Here's how the XML feed looks like: <r25:events pubdate="2010-05-19T13:58:08-04:00"> <r25:event xl:href="event.xml?event_id=328" id="BRJDMzI4" crc="00000022" status="est"> <r25:event_id>328</r25:event_id> <r25:event_name>Testing 09/2005-08/2006</r25:event_name> <r25:alien_uid/> <r25:event_priority>0</r25:event_priority> <r25:event_type_id xl:href="evtype.xml?type_id=105">105</r25:event_type_id> <r25:event_type_name>CABINET</r25:event_type_name> <r25:node_type>C</r25:node_type> <r25:node_type_name>cabinet</r25:node_type_name> <r25:state>1</r25:state> <r25:state_name>Tentative</r25:state_name> <r25:event_locator>2005-AAAAMQ</r25:event_locator> <r25:event_title/> <r25:favorite>F</r25:favorite> <r25:organization_id/> <r25:organization_name/> <r25:parent_id/> <r25:cabinet_id xl:href="event.xml?event_id=328">328</r25:cabinet_id> <r25:cabinet_name>cabinet 09/2005-08/2006</r25:cabinet_name> <r25:start_date>2005-09-01</r25:start_date> <r25:end_date>2006-08-31</r25:end_date> <r25:registration_url/> <r25:last_mod_dt>2008-02-27T14:22:43-05:00</r25:last_mod_dt> <r25:last_mod_user>abc00296004</r25:last_mod_user> </r25:event> </r25:events> And here is what I'm using for code - I'll trying to throw these into a bunch of arrays where I can format the output however I want: <?php $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, "http://somedomain.com/blah.xml"); curl_setopt ($ch, CURLOPT_HTTPHEADER, Array("Content-Type: text/xml")); curl_setopt($ch, CURLOPT_USERPWD, "username:password"); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $output = curl_exec($ch); curl_close($ch); $xml = new SimpleXmlElement($output); foreach ($xml->events->event as $entry){ $dc = $entry->children('http://www.collegenet.com/r25'); echo $entry->event_name . "<br />"; echo $entry->event_id . "<br /><br />"; }

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  • In a PHP project, how do you organize and access your helper objects?

    - by Pekka
    How do you organize and manage your helper objects like the database engine, user notification, error handling and so on in a PHP based, object oriented project? Say I have a large PHP CMS. The CMS is organized in various classes. A few examples: the database object user management an API to create/modify/delete items a messaging object to display messages to the end user a context handler that takes you to the right page a navigation bar class that shows buttons a logging object possibly, custom error handling etc. I am dealing with the eternal question, how to best make these objects accessible to each part of the system that needs it. my first apporach, many years ago was to have a $application global that contained initialized instances of these classes. global $application; $application->messageHandler->addMessage("Item successfully inserted"); I then changed over to the Singleton pattern and a factory function: $mh =&factory("messageHandler"); $mh->addMessage("Item successfully inserted"); but I'm not happy with that either. Unit tests and encapsulation become more and more important to me, and in my understanding the logic behind globals/singletons destroys the basic idea of OOP. Then there is of course the possibility of giving each object a number of pointers to the helper objects it needs, probably the very cleanest, resource-saving and testing-friendly way but I have doubts about the maintainability of this in the long run. Most PHP frameworks I have looked into use either the singleton pattern, or functions that access the initialized objects. Both fine approaches, but as I said I'm happy with neither. I would like to broaden my horizon on what is possible here and what others have done. I am looking for examples, additional ideas and pointers towards resources that discuss this from a long-term, real-world perspective. Also, I'm interested to hear about specialized, niche or plain weird approaches to the issue. Bounty I am following the popular vote in awarding the bounty, the answer which is probably also going to give me the most. Thank you for all your answers!

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  • Browser detection Plugin?

    - by chobo2
    Hi I have a website that I made and I am planning to redo it. The current version of the site used a jquery callout plugin that did not fully work in IE6. This got me thinking about browser detection. At first I was just going to put the supported browsers on the home page but then today on Digg I saw some post about some jquery plugins and wordpress and in the article there was a plugin for detecting IE. So I started to look around for some browser detection plugins. I found a few of them but they where over the top like this one sevenup Its nice but it makes a huge popup and tells them to update. This one is better then another one I found where they basically forced the user to update or they could not continue on the site. So I found this one jquery plugin This one is pretty nice since it looks at the major browsers and does detection on them too expect for chrome which I noticed triggers and an outdated browser with this plugin. So I started to look at the jquery documentation to see if they had a browser detection for chrome this is when I saw that they "Deprecated" and now recommend "Support". So now I am just confused like "Support" seems to be good and I read many posts on this site saying you should use it. But then it does not support stuff like .png detection that might have been useful to me since of that plugin(however I probably will not be using the plugin anymore since I think the author just gave up on it). Plus I don't know if this is something I am looking for at this time. Like I am guessing with "Support" you use it to detect something that is not supported and then do some alternative thing for that browser? For me I am more looking for something to tell the user "Hey look I tested this browser in the these versions of Firefox(3.5+), IE(8+), Opera(9.5+),Chrome(Something), Safari(Something). If your not using these versions you may not being seeing the site how it was intended" Of course I would try to have something shorter then that message but that the gyst. I am also assuming that the site would work in future versions of these browsers. I still check to see if my site works(they usually do) and is half decent in IE 6 but I won't spend hours fixing stuff that might be off in older browsers like IE 6. I won't test my site in older version of other browsers like firefox since I would think the user have to the sense to update so no point testing firefox 2.0 or whatever. So is there a plugin that fits this description? Or can "Support" do what I want? Thanks

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  • Dependency Injection: I don't get where to start!

    - by Andy
    I have several articles about Dependency Injection, and I can see the benefits, especially when it comes to unit testing. The units can me loosely coupled, and mocking of dependencies can be made. The trouble is - I just don't get where to start. Consider this snippet below of (much edited for the purpose of this post) code that I have. I am instantiating a Plc object from the main form, and passing in a communications mode via the Connect method. In it's present form it becomes hard to test, because I can't isolate the Plc from the CommsChannel to unit test it. (Can I?) The class depends on using a CommsChannel object, but I am only passing in a mode that is used to create this channel within the Plc itself. To use dependancy injection, I should really pass in an already created CommsChannel (via an 'ICommsChannel' interface perhaps) to the Connect method, or maybe via the Plc constructor. Is that right? But then that would mean creating the CommsChannel in my main form first, and this doesn't seem right either, because it feels like everything will come back to the base layer of the main form, where everything begins. Somehow it feels like I am missing a crucial piece of the puzzle. Where do you start? You have to create an instance of something somewhere, but I'm struggling to understand where that should be. public class Plc() { public bool Connect(CommsMode commsMode) { bool success = false; // Create new comms channel. this._commsChannel = this.GetCommsChannel(commsMode); // Attempt connection success = this._commsChannel.Connect(); return this._connected; } private CommsChannel GetCommsChannel(CommsMode mode) { CommsChannel channel; switch (mode) { case CommsMode.RS232: channel = new SerialCommsChannel( SerialCommsSettings.Default.ComPort, SerialCommsSettings.Default.BaudRate, SerialCommsSettings.Default.DataBits, SerialCommsSettings.Default.Parity, SerialCommsSettings.Default.StopBits); break; case CommsMode.Tcp: channel = new TcpCommsChannel( TCPCommsSettings.Default.IP_Address, TCPCommsSettings.Default.Port); break; default: // Throw unknown comms channel exception. } return channel; } }

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  • how get fully result from Asynchronism communication?

    - by rima
    Hi all refer to these post : here1 and here2 at last I solve my problem by build a asynchronous solution,and it work well!!! but there is a problem that i face with it,now my code is like this: class MyProcessStarter { private Process process; private StreamWriter myStreamWriter; private static StringBuilder shellOutput = null; public String GetShellOutput { get { return shellOutput.ToString(); }} public MyProcessStarter(){ shellOutput = new StringBuilder(""); process = new Process(); process.StartInfo.FileName = "sqlplus"; process.StartInfo.UseShellExecute = false; process.StartInfo.CreateNoWindow = true; process.OutputDataReceived += new DataReceivedEventHandler(ShellOutputHandler); process.StartInfo.RedirectStandardInput = true; process.StartInfo.RedirectStandardOutput = true; //process.StartInfo.RedirectStandardError = true; process.Start(); myStreamWriter = process.StandardInput; process.BeginOutputReadLine(); } private static void ShellOutputHandler(object sendingProcess,DataReceivedEventArgs outLine) { if (!String.IsNullOrEmpty(outLine.Data)) shellOutput.Append(Environment.NewLine + outLine.Data); } public void closeConnection() { myStreamWriter.Close(); process.WaitForExit(); process.Close(); } public void RunCommand(string arguments) { myStreamWriter.WriteLine(arguments); myStreamWriter.Flush(); process.WaitForExit(100); Console.WriteLine(shellOutput); Console.WriteLine("============="+Environment.NewLine); process.WaitForExit(2000); Console.WriteLine(shellOutput); } } and my input is like this: myProcesStarter.RunCommand("myusername/mypassword"); Console.writeline(myProcesStarter.GetShellOutput); but take a look at my out put: SQL*Plus: Release 11.1.0.6.0 - Production on Thu May 20 11:57:38 2010 Copyright (c) 1982, 2007, Oracle. All rights reserved. ============= SQL*Plus: Release 11.1.0.6.0 - Production on Thu May 20 11:57:38 2010 Copyright (c) 1982, 2007, Oracle. All rights reserved. Enter user-name: Connected to: Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production With the Partitioning, OLAP, Data Mining and Real Application Testing options as u see the output for run a function is not same in different time!So now would you do me a faver and help me that how I can wait until all the output done in other mean how I can customize my process to wait until output finishing ?? because I want to write a sqlcompiler so I need the exact output of shell. plz help me soon.thanxxxxxxxxxxxx :X

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  • Trying to integrate CakePHP and jQuery

    - by user198003
    Trying to integrate CakePHP and jQuery, using next example http://bakery.cakephp.org/articles/view/dynamic-select-boxes-with-ajax-jquery What I want is to when user change first option element, to automaticly fill second select option box with proper values. But, nothing happens, if you can help me why. So, there is a Invoice add form (add.ctp), with next code... <?php echo $form->create('Invoice');?> <?php echo $javascript->link('jquery.js'); $category = array('1' => 'First', '4' => 'Fourth', '7' => 'Seventh'); echo $form->input('client_id', array('options' => $category, 'empty' => 'Choose:')); echo $form->select('clientBank_id', array("Choose category first"), null, null, false); ?> <script> $("#InvoiceClientId").change(function () { $.post('/invoices/listTitleByCategory/' + $(this).val(), function(data) { $("#InvoiceClientBankId").empty().append(data); }, 'html'); }) </script> Also, there is controller (invoices_controller.php): <?php var $name = 'Invoices'; var $helpers = array('Html', 'Form', 'Time', 'Number', 'Javascript'); var $paginate = array('order' => array('Invoice.pinned DESC', 'Invoice.invoiceNumber')); var $components = array('RequestHandler'); function beforeRender(){ // prevent useless warnings for Ajax if($this->RequestHandler->isAjax()){ Configure::write('debug', 0); } } // etc... function listTitleByCategory($category = "") { $this->layout = 'ajax'; $this->beforeRender(); $this->autoRender = false; $data = $this->Invoice->Client->find('list'); echo "<option value=0>just for testing...</option>"; foreach($data as $key => $val) { echo "<option value=$key>$val</option>"; } } ?> Please, if you can help me solving this. Thank you in advance!

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  • Neo4j 1.9.4 (REST Server,CYPHER) performance issue

    - by user2968943
    I have Neo4j 1.9.4 installed on 24 core 24Gb ram (centos) machine and for most queries CPU usage spikes goes to 200% with only few concurrent requests. Domain: some sort of social application where few types of nodes(profiles) with 3-30 text/array properties and 36 relationship types with at least 3 properties. Most of nodes currently has ~300-500 relationships. Current data set footprint(from console): LogicalLogSize=4294907 (32MB) ArrayStoreSize=1675520 (12MB) NodeStoreSize=1342170 (10MB) PropertyStoreSize=1739548 (13MB) RelationshipStoreSize=6395202 (48MB) StringStoreSize=1478400 (11MB) which is IMHO really small. most queries looks like this one(with more or less WITH .. MATCH .. statements and few queries with variable length relations but the often fast): START targetUser=node({id}), currentUser=node({current}) MATCH targetUser-[contact:InContactsRelation]->n, n-[:InLocationRelation]->l, n-[:InCategoryRelation]->c WITH currentUser, targetUser,n, l,c, contact.fav is not null as inFavorites MATCH n<-[followers?:InContactsRelation]-() WITH currentUser, targetUser,n, l,c,inFavorites, COUNT(followers) as numFollowers RETURN id(n) as id, n.name? as name, n.title? as title, n._class as _class, n.avatar? as avatar, n.avatar_type? as avatar_type, l.name as location__name, c.name as category__name, true as isInContacts, inFavorites as isInFavorites, numFollowers it runs in ~1s-3s(for first run) and ~1s-70ms (for consecutive and it depends on query) and there is about 5-10 queries runs for each impression. Another interesting behavior is when i try run query from console(neo4j) on my local machine many consecutive times(just press ctrl+enter for few seconds) it has almost constant execution time but when i do it on server it goes slower exponentially and i guess it somehow related with my problem. Problem: So my problem is that neo4j is very CPU greedy(for 24 core machine its may be not an issue but its obviously overkill for small project). First time i used AWS EC2 m1.large instance but over all performance was bad, during testing, CPU always was over 100%. Some relevant parts of configuration: neostore.nodestore.db.mapped_memory=1280M wrapper.java.maxmemory=8192 note: I already tried configuration where all memory related parameters where HIGH and it didn't worked(no change at all). Question: Where to digg? configuration? scheme? queries? what i'm doing wrong? if need more info(logs, configs) just ask ;)

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  • UIScrollView Infinite Scrolling

    - by Ben Robinson
    I'm attempting to setup a scrollview with infinite (horizontal) scrolling. Scrolling forward is easy - I have implemented scrollViewDidScroll, and when the contentOffset gets near the end I make the scrollview contentsize bigger and add more data into the space (i'll have to deal with the crippling effect this will have later!) My problem is scrolling back - the plan is to see when I get near the beginning of the scroll view, then when I do make the contentsize bigger, move the existing content along, add the new data to the beginning and then - importantly adjust the contentOffset so the data under the view port stays the same. This works perfectly if I scroll slowly (or enable paging) but if I go fast (not even very fast!) it goes mad! Heres the code: - (void) scrollViewDidScroll:(UIScrollView *)scrollView { float pageNumber = scrollView.contentOffset.x / 320; float pageCount = scrollView.contentSize.width / 320; if (pageNumber > pageCount-4) { //Add 10 new pages to end mainScrollView.contentSize = CGSizeMake(mainScrollView.contentSize.width + 3200, mainScrollView.contentSize.height); //add new data here at (320*pageCount, 0); } //*** the problem is here - I use updatingScrollingContent to make sure its only called once (for accurate testing!) if (pageNumber < 4 && !updatingScrollingContent) { updatingScrollingContent = YES; mainScrollView.contentSize = CGSizeMake(mainScrollView.contentSize.width + 3200, mainScrollView.contentSize.height); mainScrollView.contentOffset = CGPointMake(mainScrollView.contentOffset.x + 3200, 0); for (UIView *view in [mainContainerView subviews]) { view.frame = CGRectMake(view.frame.origin.x+3200, view.frame.origin.y, view.frame.size.width, view.frame.size.height); } //add new data here at (0, 0); } //** MY CHECK! NSLog(@"%f", mainScrollView.contentOffset.x); } As the scrolling happens the log reads: 1286.500000 1285.500000 1284.500000 1283.500000 1282.500000 1281.500000 1280.500000 Then, when pageNumber<4 (we're getting near the beginning): 4479.500000 4479.500000 Great! - but the numbers should continue to go down in the 4,000s but the next log entries read: 1278.000000 1277.000000 1276.500000 1275.500000 etc.... Continiuing from where it left off! Just for the record, if scrolled slowly the log reads: 1294.500000 1290.000000 1284.500000 1280.500000 4476.000000 4476.000000 4473.000000 4470.000000 4467.500000 4464.000000 4460.500000 4457.500000 etc.... Any ideas???? Thanks Ben.

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  • Few doubts regarding Bitmaps , Images & `using` blocks

    - by imageWorker
    I caught up in this problem. http://stackoverflow.com/questions/2559826/garbage-collector-not-doing-its-job-memory-consumption-1-5gb-outofmemory-exc I feel that there is something wrong in my understanding. Please clarify these things. Destructor & IDisposable.Dispose are two methods for freeing resources that are not not under the control of .NET. Which means, everything except memory. right? using blocks are just better way of calling IDisposable.Dispose() method of an object. This is the main code I'm referring to. class someclass { static someMethod(Bitmap img) { Bitmap bmp = new Bitmap(img); //statement1 // some code here and return } } here is class I'm using for testing: class someotherClass { public static voide Main() { foreach (string imagePath in imagePathsArray) { using (Bitmap img1 = new Bitmap(imagePath)) { someclass.someMethod(img1); // does some more processing on `img1` } } } } Is there any memory leak with statement1? Question1: If each image size is say 10MB. Then does this bmp object occupy atleast 10MB? What I mean is, will it make completely new copy of entire image? or just refer to it? Question2:should I or should I not put the statement1 in using block? My Argument: We should not. Because using is not for freeing memory but for freeing the resources (file handle in this case). If I use it in using block. It closes file handle here encapsulated by this bmp object. It means we are also closing filehandle for the caller's img1 object. Which is not correct? As of the memory leak. No there is no scope of memory leak here. Because reference bmp is destroyed when this method is returned. Which leaves memory it refered without any pointer. So, its garbage collected. Am I right? Edit: class someclass { static Bitmap someMethod(Bitmap img) { Bitmap bmp = new Bitmap(img); //can I use `using` block on this enclosing `return bmp`; ??? // do some processing on bmp here return bmp; } }

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  • Hide jQuery Accordion while loading

    - by zac
    I am testing a site build with a slow connection and I noticed the jQuery Accordion stays expanded for a long time, until the rest of the site is loaded, and then finally collapses. Not very pretty. I was wondering how I could keep it collapsed through the loading process and only expand when clicked. I am working with the standalone 1.6 version of the accordion plugin. The basic structure : <div class="sidebar"> <ul id="navigation" class="ui-accordion-container"> <li><a class="head" href="#">1</a> <ul class="sub"> <li><a href="#">1a</a></li> <li><a href="#">2a</a></li> </ul> </li> </ul> </div> and the script jQuery().ready(function(){ jQuery('#navigation').accordion({ active: 'false', header: '.head', navigation: true, animated: 'easeslide', collapsible: true }); }); I tried to hide the elements in the CSS to keep them from appearing while loading but all that achieved is in having them always hidden. Maybe the problem is in the CSS I have a background image in each of the sub menus: #navigation{ margin:0px; margin-left: 10px; padding:0px; text-indent:0px; font-size: 1.1em; width:200px; text-transform: uppercase; padding-bottom: 30px; } #navigation ul{ border-width:0px; margin:0px; padding:0px; text-indent:0px; } #navigation li{ list-style:none outside none; } #navigation li ul{ height:185px; overflow:auto; } #navigation li ul.sub{ background:url('../images/sub.jpg') no-repeat; dispaly: block; } #navigation li li a{ color:#000000; display:block; text-indent:20px; text-decoration: none; padding: 6px 0; } #navigation li li a:hover{ background-color:#FFFF99; color:#FF0000; } Thanks in advance for any advice on how to have this thing run a little smoother and having the accordion always collapsed. -edit - I forgot to mention that I am also hoping for a solution that will allow the nav to still be accessible for those without javscript.

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  • iPhone Gps logging inaccurate

    - by Martijn
    I'm logging gps points during a walk. Below it shows the function that the coordinates are saved each 5 seconds. i Did several tests but i cannot get the right accuracy i want. (When testing the sky is clear also tests in google maps shows me that the gps signal is good). here is the code: -(void)viewDidAppear:(BOOL)animated{ if (self.locationManager == nil){ self.locationManager = [[[CLLocationManager alloc] init] autorelease]; locationManager.delegate = self; // only notify under 100 m accuracy locationManager.distanceFilter = 100.0f; locationManager.desiredAccuracy= kCLLocationAccuracyBest; [locationManager startUpdatingLocation]; } } - start logging [NSTimer scheduledTimerWithTimeInterval:5 target:self selector:@selector(getData) userInfo:nil repeats:YES]; </code> <code> -(void)getData{ int distance; // re-use location. if ([ [NSString stringWithFormat:@"%1.2f",previousLat] isEqualToString:@"0.00"]){ // if previous location is not available, do nothing distance = 0; }else{ CLLocation *loc1 = [[CLLocation alloc] initWithLatitude:previousLat longitude:previousLong]; CLLocation *loc2 = [[CLLocation alloc] initWithLatitude:latGlobal longitude:longGlobal]; distance = [loc1 getDistanceFrom: loc2]; } // overwrite latGlobal with new variable previousLat = latGlobal; previousLong = longGlobal; // store location and save data to database // this part goes ok } - (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation { // track the time to get a new gps result (for gps indicator orb) lastPointTimestamp = [newLocation.timestamp copy]; // test that the horizontal accuracy does not indicate an invalid measurement if (newLocation.horizontalAccuracy < 0) return; // test the age of the location measurement to determine if the measurement is cached // don't rely on cached measurements NSTimeInterval locationAge = -[newLocation.timestamp timeIntervalSinceNow]; if (locationAge > 5.0) return; latGlobal = fabs(newLocation.coordinate.latitude); longGlobal= fabs(newLocation.coordinate.longitude); } I have taken a screenshot of the plot results (the walk takes 30 minutes) and an example of what i'am trying to acomplish: http://www.flickr.com/photos/21258341@N07/4623969014/ i really hope someone can put me in the right direction.

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  • How to configure Jetty to reload a WebAppContext when classes are changed

    - by Guss
    I'm developing a web application and I run Jetty as the development and testing environment when I develop under Eclipse. When I make changes to Java classes, Eclipse automatically compiles them to the build directory, but Jetty won't see the changes until I stop and start the server. I know that Jetty supports "hot deployment" using ContextDeployer that will refresh updated application contexts, but it relies on a context file in a context directory being updated - which is not very useful in my case. Is there a way to set up Jetty so that it will reload the web app when any of the classes it uses is updated? My current jetty.xml looks something like this: <?xml version="1.0"?> <!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd"> <Configure id="Server" class="org.eclipse.jetty.server.Server"> <Set name="ThreadPool"><!-- bla bla --></Set> <Call name="addConnector"><!-- bla bla --></Call> <Set name="handler"> <New id="Handlers" class="org.eclipse.jetty.server.handler.HandlerCollection"> <Set name="handlers"> <Array type="org.eclipse.jetty.server.Handler"> <Item> <New id="webapp" class="org.eclipse.jetty.webapp.WebAppContext"> <Set name="displayName">My Web App</Set> <Set name="resourceBase">src/main/webapp</Set> <Set name="descriptor">src/main/webapp/WEB-INF/web.xml</Set> <Set name="contextPath">/mywebapp</Set> </New> </Item> <Item> <New id="DefaultHandler" class="org.eclipse.jetty.server.handler.DefaultHandler"/> </Item> </Array> </Set> </New> </Set> </Configure>

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  • Specifying a Single Request To Use Credentials with HttpClient

    - by jiduvah
    I am using OAuth2 on my android project. The idea is to use a singleton HttpClient used with a ThreadSafeClientConnManager. For a normal request to the server we construct an Authorization header and send that. The header is constructed from values received from the server. This works fine. However every 15 minutes we must get new values from the server to construct the header. To Received these values I must set the credentials like so. client.getCredentialsProvider().setCredentials( new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT), new UsernamePasswordCredentials(creds.clientId, creds.clientSecret)); In order for this to work I must set up and new DefaultHttpClient. If I use the original singleton httpclient I receive some errors. My question is.. is it possible to set the credentials to be used only on this one request? I noticed that there is an AuthScope. The host and port would not be suitable for this but maybe the realm would? I can't find anything that tells me what a realm is or how to use it. 06-05 10:12:55.969: W/System.err(23843): org.apache.http.NoHttpResponseException: The target server failed to respond 06-05 10:12:55.969: W/System.err(23843): at org.apache.http.impl.conn.DefaultResponseParser.parseHead(DefaultResponseParser.java:85) 06-05 10:12:55.969: W/System.err(23843): at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:174) 06-05 10:12:55.969: W/System.err(23843): at org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(AbstractHttpClientConnection.java:179) 06-05 10:12:55.969: W/System.err(23843): at org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(DefaultClientConnection.java:235) 06-05 10:12:55.969: W/System.err(23843): at org.apache.http.impl.conn.AbstractClientConnAdapter.receiveResponseHeader(AbstractClientConnAdapter.java:259) 06-05 10:12:55.975: W/System.err(23843): at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:279) 06-05 10:12:55.975: W/System.err(23843): at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:121) 06-05 10:12:55.975: W/System.err(23843): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:504) 06-05 10:12:55.975: W/System.err(23843): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 06-05 10:12:55.975: W/System.err(23843): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 06-05 10:12:55.975: W/System.err(23843): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465) So After more testing I have found where the problem lies. I want to configure a pooled connection manager like so SchemeRegistry schemeRegistry = new SchemeRegistry(); schemeRegistry.register( new Scheme("http", PlainSocketFactory.getSocketFactory(), 80)); schemeRegistry.register( new Scheme("https", PlainSocketFactory.getSocketFactory(), 443)); ClientConnectionManager conManager = new ThreadSafeClientConnManager(new BasicHttpParams(), schemeRegistry); DefaultHttpClient httpClient = new DefaultHttpClient(); But when configure like this, I get the error above. If I use the normal default httpclient like so DefaultHttpClient httpClient = new DefaultHttpClient(); Then it works fine. Any ideas?

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  • WPF: Improving Performance for Running on Older PCs

    - by Phil Sandler
    So, I'm building a WPF app and did a test deployment today, and found that it performed pretty poorly. I was surprised, as we are really not doing much in the way of visual effects or animations. I deployed on two machines: the fastest and the slowest that will need to run the application (the slowest PC has an Intel Celeron 1.80GHz with 2GB RAM). The application ran pretty well on the faster machine, but was choppy on the slower machine. And when I say "choppy", I mean the cursor jumped even just passing it over any open window of the app that had focus. I opened the Task Manager Performance window, and could see that the CPU usage jumped whenever the app had focus and the cursor was moving over it. If I gave focus to another (e.g. Excel), the CPU usage went back down after a second. This happened on both machines, but the choppiness was only noticeable on the slower machine. I had very limited time to tinker on the deployment machines, so didn't do a lot of detailed testing. The app runs fine on my development machine, but I also see the CPU spiking up to 10% there, just running the cursor over the window. I downloaded the WPF performance tool from MS and have been tinkering with it (on my dev machine). The docs say this about the "Frame Rate" metric in the Perforator tool: For applications without animation, this value should be near 0. The app is not doing any heavy animation, but the frame rate stays near 50 when the cursor is over any window. The screens I tested on have column headers in a grid that "highlight" and buttons that change color and appearance when scrolled over. Even moving the mouse on blank areas of the windows cause the same Frame rate and CPU usage (doesn't seem to be related to these minor animations). (Also, I am unable to figure out how to get anything but the two default tools--Perforator and Visual Profiler--installed into the WPF performance tool. That is probably a separate question). I also have Redgate's profiling tool, but I'm not sure if that can shed any light on rendering performance. So, I realize this is not an easy thing to troubleshoot without specifics or sample code (which I can't post). My questions are: What are some general things to look for (or avoid) in the code to improve performance? What steps can I take using the WPF performance tool to narrow down the problem? Is the PC spec listed above (Intel Celeron 1.80GHz with 2GB RAM) too slow to be running even vanilla WPF applications?

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  • Hibernate MappingException Unknown entity: $Proxy2

    - by slynn1324
    I'm using Hibernate annotations and have a VERY basic data object: import java.io.Serializable; import javax.persistence.Entity; import javax.persistence.Id; @Entity public class State implements Serializable { /** * */ private static final long serialVersionUID = 1L; @Id private String stateCode; private String stateFullName; public String getStateCode() { return stateCode; } public void setStateCode(String stateCode) { this.stateCode = stateCode; } public String getStateFullName() { return stateFullName; } public void setStateFullName(String stateFullName) { this.stateFullName = stateFullName; } } and am trying to run the following test case: public void testCreateState(){ Session s = HibernateUtil.getSessionFactory().getCurrentSession(); Transaction t = s.beginTransaction(); State state = new State(); state.setStateCode("NE"); state.setStateFullName("Nebraska"); s.save(s); t.commit(); } and get an org.hibernate.MappingException: Unknown entity: $Proxy2 at org.hibernate.impl.SessionFactoryImpl.getEntityPersister(SessionFactoryImpl.java:628) at org.hibernate.impl.SessionImpl.getEntityPersister(SessionImpl.java:1366) at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:121) .... I haven't been able to find anything referencing the $Proxy part of the error - and am at a loss.. Any pointers to what I'm missing would be greatly appreciated. hibernate.cfg.xml <property name="hibernate.connection.driver_class">org.hsqldb.jdbcDriver</property> <property name="connection.url">jdbc:hsqldb:hsql://localhost/xdb</property> <property name="connection.username">sa</property> <property name="connection.password"></property> <property name="current_session_context_class">thread</property> <property name="dialect">org.hibernate.dialect.HSQLDialect</property> <property name="show_sql">true</property> <property name="hbm2ddl.auto">update</property> <property name="hibernate.transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property> <mapping class="com.test.domain.State"/> in HibernateUtil.java public static SessionFactory getSessionFactory(boolean testing ) { if ( sessionFactory == null ){ try { String configPath = HIBERNATE_CFG; AnnotationConfiguration config = new AnnotationConfiguration(); config.configure(configPath); sessionFactory = config.buildSessionFactory(); } catch (Exception e){ e.printStackTrace(); throw new ExceptionInInitializerError(e); } } return sessionFactory; }

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  • Rails Tutorial Chapter 4 2nd Ed. Title Helper not being called with out argument.

    - by SuddenlyAwakened
    I am running through the Rails Tutorial by Michael Hartl (Screen Cast). Ran into the and issue in chapter 4 on the title helper. I have been putting my own twist on the code as I go to make sure I understand it all. However on this one I it is very similar and I am not quite sure why it is acting the way it is. Here is the code: Application.html.erb <!DOCTYPE html> <html> <head> <%- Rails.logger.info("Testing: #{yield(:title)}") %> <title><%= full_title(yield(:title)) %></title> <%= stylesheet_link_tag "application", :media => "all" %> <%= javascript_include_tag "application" %> <%= csrf_meta_tags %> </head> <body> <%= yield %> </body> </html> Application_helper.rb module ApplicationHelper def full_title(page_title) full_title = "Ruby on Rails Tutorial App" full_title += " | #{page_title}" unless page_title.blank? end end Home.html.erb <h1><%= t(:sample_app) %></h1> <p> This is the home page for the <a href="http://railstutorial.org/">Ruby on Rails Tutorial</a> sample application </p> about.html.erb <% provide(:title, t(:about_us)) %> <h1><%= t(:about_us) %></h1> <p> The <a href="http://railstutorial.org/">Ruby on Rails Tutorial</a> is a project to make a book and screencast to teach web development with <a href="http://railstutorial.org/">Ruby on Rails</a>. This is the sample application for the tutorial. </p> What Happens: The code works fine when I set the provide method like on the about page. However when I do not it does not seem to even call the helper. I am assuming that because no title is passed back. Any ideas on what I am doing wrong? Thank you all for your help.

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  • How to develop a Jquery plugin to find the first child that match with a selector?

    - by Ivan
    I'm trying to make a Jquery plugin (findFirst()) to find the first child with a given characteristics (something in the middle of the find() and children() functions. For instance, given this markup: <div id="start"> <div> <span>Hello world</span> <ul class="valid-result"> ... </ul> <ul class="valid-result"> <li> <ul class="not-a-result"> ... </ul> </li> </ul> <div> <ul class="valid-result"> ... </ul> </div> </div> </div> If you ask for $("#start").findFirst('ul') it should return all ul lists that I have tagged with the valid-result class, but not the ul with class not-a-result. It is, this function has to find the first elements that matches with a given selector, but not the inner elements that match this selector. This is the first time I try to code a Jquery function, and what I've already read doesn't helps me too much with this. The function I have developed is this: jQuery.fn.findFirst = function (sel) { return this.map(function() { return $(this).children().map(function() { if ($(this).is(sel)) { return $(this); } else { return $(this).findFirst(sel); } }); }); } It works in the sense it tries to return the expected result, but the format it returns the result is very rare for me. I suppose the problem is something I don't understand about Jquery. Here you have the JFiddle where I'm testing. EDIT The expected result after $("#start").findFirst('ul') is a set with all UL that have the class 'valid-result' BUT it's not possible to use this class because it doesn't exist in a real case (it's just to try to explain the result). This is not equivalent to first(), because first returns only one element!

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  • Mocking methods that call other methods Still hit database.Can I avoid it?

    - by devnet247
    Hi, It has been decided to write some unit tests using moq etc..It's lots of legacy code c# (this is beyond my control so cannot answer the whys of this) Now how do you cope with a scenario when you dont want to hit the database but you indirectly still hit the database? This is something I put together it's not the real code but gives you an idea. How would you deal with this sort of scenario? Basically calling a method on a mocked interface still makes a dal call as inside that method there are other methods not part of that interface?Hope it's clear [TestFixture] public class Can_Test_this_legacy_code { [Test] public void Should_be_able_to_mock_login() { var mock = new Mock<ILoginDal>(); User user; var userName = "Jo"; var password = "password"; mock.Setup(x => x.login(It.IsAny<string>(), It.IsAny<string>(),out user)); var bizLogin = new BizLogin(mock.Object); bizLogin.Login(userName, password, out user); } } public class BizLogin { private readonly ILoginDal _login; public BizLogin(ILoginDal login) { _login = login; } public void Login(string userName, string password, out User user) { //Even if I dont want to this will call the DAL!!!!! var bizPermission = new BizPermission(); var permissionList = bizPermission.GetPermissions(userName); //Method I am actually testing _login.login(userName,password,out user); } } public class BizPermission { public List<Permission>GetPermissions(string userName) { var dal=new PermissionDal(); var permissionlist= dal.GetPermissions(userName); return permissionlist; } } public class PermissionDal { public List<Permission> GetPermissions(string userName) { //I SHOULD NOT BE GETTING HERE!!!!!! return new List<Permission>(); } } public interface ILoginDal { void login(string userName, string password,out User user); } public interface IOtherStuffDal { List<Permission> GetPermissions(); } public class Permission { public int Id { get; set; } public string Name { get; set; } } Any suggestions? Am I missing the obvious? Is this Untestable code? Very very grateful for any suggestions.

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  • How to handle environment-specific application configuration organization-wide?

    - by Stuart Lange
    Problem Your organization has many separate applications, some of which interact with each other (to form "systems"). You need to deploy these applications to separate environments to facilitate staged testing (for example, DEV, QA, UAT, PROD). A given application needs to be configured slightly differently in each environment (each environment has a separate database, for example). You want this re-configuration to be handled by some sort of automated mechanism so that your release managers don't have to manually configure each application every time it is deployed to a different environment. Desired Features I would like to design an organization-wide configuration solution with the following properties (ideally): Supports "one click" deployments (only the environment needs to be specified, and no manual re-configuration during/after deployment should be necessary). There should be a single "system of record" where a shared environment-dependent property is specified (such as a database connection string that is shared by many applications). Supports re-configuration of deployed applications (in the event that an environment-specific property needs to change), ideally without requiring a re-deployment of the application. Allows an application to be run on the same machine, but in different environments (run a PROD instance and a DEV instance simultaneously). Possible Solutions I see two basic directions in which a solution could go: Make all applications "environment aware". You would pass the environment name (DEV, QA, etc) at the command line to the app, and then the app is "smart" enough to figure out the environment-specific configuration values at run-time. The app could fetch the values from flat files deployed along with the app, or from a central configuration service. Applications are not "smart" as they are in #1, and simply fetch configuration by property name from config files deployed with the app. The values of these properties are injected into the config files at deploy-time by the install program/script. That install script takes the environment name and fetches all relevant configuration values from a central configuration service. Question How would/have you achieved a configuration solution that solves these problems and supports these desired features? Am I on target with the two possible solutions? Do you have a preference between those solutions? Also, please feel free to tell me that I'm thinking about the problem all wrong. Any feedback would be greatly appreciated.

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  • c++ class member functions instatiated by traits

    - by Jive Dadson
    I am reluctant to say I can't figure this out, but I can't figure this out. I've googled and searched stackoverflow, and come up empty. The abstract, and possibly overly vague form of the question is, how can I use the traits-pattern to instantiate non-virtual member functions? The question came up while modernizing a set of multivariate function optimizers that I wrote more than 10 years ago. The optimizers all operate by selecting a straight-line path through the parameter space away from the current best point (the "update"), then finding a better point on that line (the "line search"), then testing for the "done" condition, and if not done, iterating. There are different methods for doing the update, the line-search, and conceivably for the done test, and other things. Mix and match. Different update formulae require different state-variable data. For example, the LMQN update requires a vector, and the BFGS update requires a matrix. If evaluating gradients is cheap, the line-search should do so. If not, it should use function evaluations only. Some methods require more accurate line-searches than others. Those are just some examples. The original version instantiates several of the combinations by means of virtual functions. Some traits are selected by setting mode bits that are tested at runtime. Yuck. It would be trivial to define the traits with #define's and the member functions with #ifdef's and macros. But that's so twenty years ago. It bugs me that I cannot figure out a whiz-bang modern way. If there were only one trait that varied, I could use the curiously recurring template pattern. But I see no way to extend that to arbitrary combinations of traits. I tried doing it using boost::enable_if, etc.. The specialized state info was easy. I managed to get the functions done, but only by resorting to non-friend external functions that have the this-pointer as a parameter. I never even figured out how to make the functions friends, much less member functions. The compiler (vc++ 2008) always complained that things didn't match. I would yell, "SFINAE, you moron!" but the moron is probably me. Perhaps tag-dispatch is the key. I haven't gotten very deeply into that. Surely it's possible, right? If so, what is best practice?

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