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• Selective replication with CouchDB

  - by FRotthowe

  I'm currently evaluating possible solutions to the follwing problem: A set of data entries must be synchonized between multiple clients, where each client may only view (or even know about the existence of) a subset of the data. Each client "owns" some of the elements, and the decision who else can read or modify those elements may only be made by the owner. To complicate this situation even more, each element (and each element revision) must have an unique identifier that is equal for all clients. While the latter sounds like a perfect task for CouchDB (and a document based data model would fit my needs perfectly), I'm not sure if the authentication/authorization subsystem of CouchDB can handle these requirements: While it should be possible to restict write access using validation functions, there doesn't seem to be a way to authorize read access. All solutions I've found for this problem propose to route all CouchDB requests through a proxy (or an application layer) that handles authorization. So, the question is: Is it possible to implement an authorization layer that filters requests to the database so that access is granted only to documents that the requesting client has read access to and still use the replication mechanism of CouchDB? Simplified, this would be some kind of "selective replication" where only some of the documents, and not the whole database is replicated. I would also be thankful for directions to some detailed information about how replication works. The CouchDB wiki and even the "Definite Guide" Book are not too specific about that.

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• I can't compile this code

  - by heshim

  #include <stdio.h> #define IN 1 /* inside a word */ #define OUT 0 /* outside a word */ /* count lines, words, and characters in input */ main() { int c, nl, nw, nc, state; state = OUT; nl = nw = nc = 0; while ((c = getchar()) != EOF) { ++nc; if (c == '\n') ++nl; if (c == ' ' || c == '\n' || c = '\t') state = OUT; else if (state == OUT) { state = IN; ++nw; } } printf("%d %d %d\n", nl, nw, nc); } I got K&R book but there are some codes that don't compile ! it gives me - 19 C:\Users\Nom\Desktop\Untitled1.c invalid lvalue in assignment edit: now it works, thanks guys, but now it does nothing ! the printf statement doesn't work. It opens the dos console, I type anything and it just return a new line. I'm using Dev-C++ 4.9.9.2 I put the printf statement inside the while loop and it works now. thanks

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• uploading database file in assets not returning a record

  - by Alexander

  I have a problem with a database file not being read I have added the database file in assets called mydb but when i run my code it says its not being located. It is calling this toast Toast.makeText(this, "No contact found", Toast.LENGTH_LONG).show(); This is being called because no records are being returned. This is an example form Android Application Development book. public class DatabaseActivity extends Activity { /** Called when the activity is first created. */ TextView quest, response1, response2; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); TextView quest = (TextView) findViewById(R.id.quest); try { String destPath = "/data/data/" + getPackageName() + "/databases/MyDB"; File f = new File(destPath); if (!f.exists()) { CopyDB( getBaseContext().getAssets().open("mydb"), new FileOutputStream(destPath)); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } DBAdapter db = new DBAdapter(this); //---get a contact--- db.open(); Cursor c = db.getContact(2); if (c.moveToFirst()) DisplayContact(c); else Toast.makeText(this, "No contact found", Toast.LENGTH_LONG).show(); db.close(); } public void CopyDB(InputStream inputStream, OutputStream outputStream) throws IOException { //---copy 1K bytes at a time--- byte[] buffer = new byte[1024]; int length; while ((length = inputStream.read(buffer)) > 0) { outputStream.write(buffer, 0, length); } inputStream.close(); outputStream.close(); } public void DisplayContact(Cursor c) { quest.setText(String.valueOf(c.getString(1))); //quest.setText(String.valueOf("this is a text string")); } }

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• Unit testing a 'legacy' WPF Application

  - by sc_ray

  The product I have been working on has been in development for the past six years. It started as a generic data entry portal into an insanely complex part WPF/part legacy application. The system has been developed for all these years without a single Unit test in its fold. Now, the point has been raised for a comprehensive unit testing framework. I have been recruited recently to work on this product and have been tasked to get the 'Testing' in order. Since the team that worked on the product for the last six years adopted 'Agile', the project lacks any documentation of the business rules or any design documents. I have been trying to write unit tests for some of the modules. But I am not sure what to Mock, how to setup my Test fixture and eventually what to Test for, since a casual glance of the methods does not reveal its intentions. Also, it has come to my attention that the code was not developed with a particular methodology in mind. Given the situation, I was wondering if the good people of Stackoverflow could provide me with some advise on how to salvage this situation. I have heard about the book 'Working with Legacy Code' that has something to say about this general situation but I was thinking about getting some pointers from individuals who have encountered similar situations within the technology stack(C#,VB,C++,.NET 3.5,WCF,SQL Server 2005).

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• A question about TBB/C++ code

  - by Jackie

  I am reading The thread building block book. I do not understand this piece of code: FibTask& a=*new(allocate_child()) FibTask(n-1,&x); FibTask& b=*new(allocate_child()) FibTask(n-2,&y); What do these directive mean? class object reference and new work together? Thanks for explanation. The following code is the defination of this class FibTask. class FibTask: public task { public: const long n; long* const sum; FibTask(long n_,long* sum_):n(n_),sum(sum_) {} task* execute() { if(n FibTask& a=*new(allocate_child()) FibTask(n-1,&x); FibTask& b=*new(allocate_child()) FibTask(n-2,&y); set_ref_count(3); spawn(b); spawn_and_wait_for_all(a); *sum=x+y; } return 0; } };

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• Threading in Android

  - by virsir

  I am currently developing Android app, it needs download content from internet. I use thread to do that and then call runOnUiThread method to update GUI. I placed a refresh menu on it, if user tried to refresh the content, the download thread will be created and started. The problem is that how can I control the thread order, I need to accept the latest request's response and abandon previous thread requests if there were some other requests still running because the request parameters may have been changed by user. Currently I was using a threadId to do this thing, when a thread finished, it will check its threadId, if it was the latest recored one, it then takes control and render the response. My question is that is there any other proper better solution for this? Do I need to stop threads when user exit the app? I remember that some book said that do not try stop thread manually and wait itself finish is a good practice, is that true? Should I stop them by calling "stop" or "interrupt" method? I read some documents around threading in Android and found the class HandlerThread, what is it? In what kind of situation I need to use it?

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• AttributeError in my Python program regarding classes

  - by Axel Finkel

  I'm doing an exercise out of the Python book that involves creating a class and a subclass. I am getting the following error when I try to run the program: AttributeError: 'Customer' object has no attribute 'name', when it tries to go through this bit of code: self.name.append(name) As this is my first time dealing with classes and objects in Python, I'm sure I am making some overt mistake somewhere, but I can't seem to figure it out. I've looked over the documentation for creating classes and writing member functions, and it looks correct, but it is obviously not. I want the Customer subclass to inherit the name, address, and telephone attributes from the Person superclass, but it doesn't seem to be doing so? Here is my code: class Person: def __init__(self): self.name = None self.address = None self.telephone = None def changeName(self, name): self.name.append(name) def changeAddress(self, address): self.address.append(address) def changeTelephone(self, telephone): self.telephone.append(telephone) class Customer(Person): def __init__(self): self.customerNumber = None self.onMailingList = False def changeCustomerNumber(self, customerNumber): self.customerNumber.append(customerNumber) def changeOnMailingList(): if onMailingList == False: onMailingList == True else: onMailingList == False def main(): customer1 = Customer() name = 'Bob Smith' address = '123 Somewhere Road' telephone = '111 222 3333' customerNumber = '12345' customer1.changeName(name) customer1.changeAddress(address) customer1.changeTelephone(telephone) customer1.changeCustomerNumber(customerNumber) print("Customer name: " + customer1.name) print("Customer address: " + customer1.address) print("Customer telephone number: " + customer1.telephone) print("Customer number: " + customer1.customerNumber) print("On mailing list: " + customer1.OnMailingList) customer1.changeOnMailingList() print("On mailing list: " + customer1.OnMailingList) main()

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• File writing problem on Windows 7 Professional in c#

  - by Ummar

  I have an application in C# which I write some data to file. I am facing the problem on windows 7 professional that when I write data to C:\ProgramData, Access denied acception is thrown. If I login from an administrator account this issue vanishes, and if I login from some other account who have administrative previlages this issue comes up. This issue is only produces on windows 7 professional, it is working fine on all other flavors of windows 7 as well as windows vista. try { XmlTextWriter myXmlTextWriter = new XmlTextWriter("Configuration.xml", null); myXmlTextWriter.Formatting = Formatting.Indented; myXmlTextWriter.WriteStartDocument(true); myXmlTextWriter.WriteDocType("ApplicationConfigurations", null, null, null); ////myXmlTextWriter.WriteComment("This file represents another fragment of a book store inventory database"); myXmlTextWriter.WriteStartElement("Configuration"); myXmlTextWriter.WriteElementString("firstElement", pe.ToString()); myXmlTextWriter.WriteEndElement(); myXmlTextWriter.WriteEndDocument(); myXmlTextWriter.Flush(); myXmlTextWriter.Close(); }catch(Exception e) { //Exception is thrown in Win7 professional }

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• When asked "How do I make a website?" how do you answer?

  - by Luke CK

  A (non-technical) friend of mine has asked me how to make a website. I get this question all the time. After a few questions I found out that she has an idea that could turn into a commercial site. I described three options to her: a) Get a book/enroll in a class/follow some online tutorials and learn how to do it. She's pretty smart and her personality seems like a good match for this sort of thing so I'm sure she could learn but she doesn't have a lot of time spare. Maybe if she started with one of those WYSIWYG editors at first? I stressed that this would take a longer than a couple of weekends of playing around. b) Hire someone to build it. Ranges from ultra cheap to ultra expensive, crappy to good and everything in between. I didn't mention sites like Rentacoder because she hasn't worked on a project like this before and doesn't know what to ask for. At this stage she'd likely ask for a Youtube-MySpace-Google for a few hundred bucks because she doesn't yet understand just how much is involved. c) Find someone technical and partner up with them. I explained that this can either work really well or be a disaster because she'd have to give up some of her ownership of the idea. How do you respond in these situations?

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• Need help/guidance about creating a desktop application with gui

  - by Somebody still uses you MS-DOS

  I'm planning to do an Desktop application using Python, to learn some Desktop concepts. I'm going to use GTK or Qt, I still haven't decided which one. Fact is: I would like to create an application with the possibility to be called from command line, AND using a GUI. So it would be useful for cmd fans, and GUI users as well. It would be interesting to create a web interface too in the future, so it could be run in a server somewhere using an html interface created with a template language. I'm thinking about two approaches: - Creating a "model" with a simple interface which is called from a desktop/web implementation; - Creating a "model" with an html interface, and embeb a browser component so I could reuse all the code in both desktop/web scenarios. My question is: which exactly concepts are involved in this project? What advantages/disadvantages each approach has? Are they possible? By naming "interface", I'm planning to just do some interfaces.py files with def calls. Is this a bad approach? I would like to know some book recommendations, or resources to both options - or source code from projects which share the same GUI/cmd/web goals I'm after. Thanks in advance!

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• How to tell if leaving iOS app entered foreground from fast-app switching or manually?

  - by JPK

  Is there a way to tell if an iOS app enters the foreground from fast-app switching or manually? I need to know by the time applicationWillEnterForeground is called, so some specific code can be executed (or not executed) depending on the condition in which the app entered the foreground. EDIT: It turned out that this was more of a design issue for me. I moved my code to applicationDidBecomeActive. I also added a BOOL property to the appDelegate called fastAppSwitching (probably the wrong name for it). I set this to YES in application:handleOpenURL and application:openURL:sourceApplication:annotation. Then I added the following code to application:didFinishLaunchingWithOptions: if (launchOptions) { self.fastAppSwitching = YES; } else { self.fastAppSwitching = NO; } In applicationDidBecomeActive, I used the following code: if (fastAppSwitching == YES) { self.fastAppSwitching = NO; //stop, don't go any further } else { ... } EDIT2: MaxGabriel makes a good point below: "Just a warning to others taking the solution described here, applicationDidBecomeActive: is called when the user e.g. ignores a phone call or text message, unlike applicationWillEnterForeground". This is actually also true for in-app purchases and Facebook in-app authorization (new in iOS 6). So, with some further testing, this is the current solution: Add a new Bool called passedThroughWillEnterForeground. In applicationWillResignActive: self.passedThroughWillEnterForeground = NO; In applicationDidEnterBackground: self.passedThroughWillEnterForeground = NO; In applicationWillEnterForeground: self.passedThroughWillEnterForeground = YES; In applicationDidBecomeActive: if (passedThroughWillEnterForeground) { //we are NOT returning from 6.0 (in-app) authorization dialog or in-app purchase dialog, etc //do nothing with this BOOL - just reset it self.passedThroughWillEnterForeground = NO; } else { //we ARE returning from 6.0 (in-app) authorization dialog or in-app purchase dialog - IE //This is the same as fast-app switching in our book, so let's keep it simple and use this to set that self.fastAppSwitching = YES; } if (fastAppSwitching == YES) { self.fastAppSwitching = NO; } else { ... } EDIT3: I think we also need a bool to tell if app was launched from terminated.

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• using action helpers in Zend Framework 1.8

  - by Nasser

  Hi am starting off with Zend Framework and have a question about action helpers. My first application is a simple authentication system (following a tutorial from a book). The registration and authentication seems to work fine but the redirect doesn't. I have a customer controller that has this among others: class CustomerController extends Zend_Controller_Action { // some code here...... public function authenticateAction() { $request = $this->getRequest(); if (!$request->isPost()) { return $this->_helper->redirector('login'); } // Validate $form = $this->_forms['login']; if (!$form->isValid($request->getPost())) { return $this->render('login'); } if (false === $this->_authService->authenticate($form->getValues())) { $form->setDescription('Login failed, please try again.'); return $this->render('login'); } return $this->_helper->redirector('index'); } the authenticate url is http://localhost/customer/authenticate and this seems to work fine but it does not redirect. After authentication I get a blank page which looks like its taking me to the index and just sits there. I tried using '/index' instead but that did not help either. Do I need to do anything special to make the redirector helper work? I have a logout action which behaves the same.

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• PNG's In Mac on Java cause massive CPU usage

  - by alexganose

  Hey, I've been having this problem for a while now and I was hoping someone could help. I make small games using Java on Mac OSX 1.6.3 and if I use PNG's as the image format my CPU usage by Java skyrockets to say 50% (on a very small 2D game). However if I use GIF as the format my CPU usage by Java stays constant at 10% which is reasonable. What is causing this problem?? It occurs on every game I develop using PNG's so I always just switch to GIF's. The problem is now that i need to use a PNG for its variable alpha properties rather than just plain transparency. This is not available using GIF's. The problem is present on Java SE 6 and previous versions. I am using an early 2009 Mac Book Pro 15". The problem does not occur on a Windows PC running the same game. The CPU usage due to Java using PNG's on a Windows PC (I have tried XP, Vista and 7) is always constantly low at ~10%. Any help would be greatly appreciated. Thanks :)

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• How do I access a value of a nested Perl hash?

  - by st

  I am new to Perl and I have a problem that's very simple but I cannot find the answer when consulting my Perl book. When printing the result of Dumper($request); I get the following result: $VAR1 = bless( { '_protocol' => 'HTTP/1.1', '_content' => '', '_uri' => bless( do{\(my $o = 'http://myawesomeserver.org:8081/counter/')}, 'URI::http' ), '_headers' => bless( { 'user-agent' => 'Mozilla/5.0 (X11; U; Linux i686; en; rv:1.9.0.4) Gecko/20080528 Epiphany/2.22 Firefox/3.0', 'connection' => 'keep-alive', 'cache-control' => 'max-age=0', 'keep-alive' => '300', 'accept' => 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8', 'accept-language' => 'en-us,en;q=0.5', 'accept-encoding' => 'gzip,deflate', 'host' => 'localhost:8081', 'accept-charset' => 'ISO-8859-1,utf-8;q=0.7,*;q=0.7' }, 'HTTP::Headers' ), '_method' => 'GET', '_handle' => bless( \*Symbol::GEN0, 'FileHandle' ) }, 'HTTP::Server::Simple::Dispatched::Request' ); How can I access the values of '_method' ('GET') or of 'host' ('localhost:8081'). I know that's an easy question, but Perl is somewhat cryptic at the beginning.

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• Should I learn two (or more) programming languages in parallel?

  - by c_maker

  I found entries on this site about learning a new programming language, however, I have not come across anything that talks about the advantages and disadvantages of learning two languages at the same time. Let's say my goal is to learn two new languages in a year. I understand that the definition of learning a new language is different for everyone and you can probably never know everything about a language. I believe in most cases the following things are enough to include the language in your resume and say that you are proficient in it (list is not in any particular order): Know its syntax so you can write a simple program in it Compare its underlying concepts with concepts of other languages Know best practices Know what libraries are available Know in what situations to use it Understand the flow of a more complex program At least know most of what you do not know I would probably look for a good book and pick an open source project for both of these languages to start with. My questions: Is it best to spend 5 months learning language#1 then 5 months learning language#2, or should you mix the two. Mixing them I mean you work on them in parallel. Should you pick two languages that are similar or different? Are there any advantages/disadvantages of let's say learning Lisp in tandem with Ruby? Is it a good idea to pick two languages with similar syntax or would it be too confusing? Please tell me what your experiences are regarding this. Does it make a difference if you are a beginner or a senior programmer?

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• Saving and restoring OpenGL model-view

  - by Tom

  I am a new-comer to OpenGL, and much of it remains mysterious to my feeble brain. I have been studying the NeHe demos as well as the Red Book. I am writing an Android application that displays the Earth in the center of the screen. The user can rotate the Earth about any axis (much like a very simple "Google Earth"). This code is working (I based it on the NeHe examples). Now I want to add a feature; the user should be able to save the current model orientation, then later return to that same orientation. For example, the user may save the Earth orientation such that the viewer is looking down at her hometown, and north-east is "up". How do I do this with OpenGL-ES? To capture and save the current orientation, my code could get the current model-view transformation matrix - I think I understand how to do that. But later on how do I apply that saved matrix to restore the view?

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• Problem with Java FX Look and Feel

  - by drachenfels

  Hi, I was looking at some of the examples from the Deitel and Deitel's book for Programming in Java, and one of the first examples is a very simple Swing display. Hence this snippet of code : import javax.swing.*; public class cdea { public static void main(String args[]){ JOptionPane.showMessageDialog(null,"\"Welcome to Java Programming!\""); System.exit(0); //end method main } } I read some stuff regarding how one can get native UI look and feel by using UIManager.setLookAndFeel( UIManager.getSystemLookAndFeelClassName()); to the program. However, when I just add this to my main method, it gives me a host of errors. Specifically : Multiple markers at this line - Unhandled exception type IllegalAccessException - Unhandled exception type InstantiationException - Unhandled exception type ClassNotFoundException - Unhandled exception type UnsupportedLookAndFeelException However when I use it as part of a try/catch exception loop (is that what it is called?) as detailed on http://stackoverflow.com/questions/1590863/getting-java-applications-to-look-native-on-windows-how , I get the program running properly. Could anyone tell me in simple language why this is so? As in, why can't I directly get the System look and feel; why do I have to use it with exception handling? I'm new to Java, and OOP in general, so I'm sorry if I'm being too simplistic.

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• How can I exclude LEFT JOINed tables from TOP in SQL Server?

  - by Kalessin

  Let's say I have two tables of books and two tables of their corresponding editions. I have a query as follows: SELECT TOP 10 * FROM (SELECT hbID, hbTitle, hbPublisherID, hbPublishDate, hbedID, hbedDate FROM hardback LEFT JOIN hardbackEdition on hbID = hbedID UNION SELECT pbID, pbTitle, pbPublisher, pbPublishDate, pbedID, pbedDate FROM paperback Left JOIN paperbackEdition on pbID = pbedID ) books WHERE hbPublisherID = 7 ORDER BY hbPublishDate DESC If there are 5 editions of the first two hardback and/or paperback books, this query only returns two books. However, I want the TOP 10 to apply only to the number of actual book records returned. Is there a way I can select 10 actual books, and still get all of their associated edition records? In case it's relevant, I do not have database permissions to CREATE and DROP temporary tables. Thanks for reading! Update To clarify: The paperback table has an associated table of paperback editions. The hardback table has an associated table of hardback editions. The hardback and paperback tables are not related to each other except to the user who will (hopefully!) see them displayed together.

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• checking is username exists on two tables PHP PDO?

  - by PHPLOVER

  Me again. I have a users table and a users_banlist table. On my registration form i want to check all in one query whether the username someone entered on form exists in the users table and see if it also exists on the users_banlist table. I can do them on there own in individual queries but would rather do it all in one. Here is what i got, but even thou i enter a username that is taken it does not tell me its already taken. $stmt = $dbh->prepare(" SELECT users.user_login, users_banlist.user_banlist FROM users , users_banlist WHERE users.user_login = ? OR users_banlist.user_banlist = ?"); // checker if username exists in users table or users_banlist table $stmt->execute(array($username, $username)); if ( $stmt->rowCount() > 0 ) { $error[] = 'Username already taken'; } Basically i think it is something to do with the execute or rowCount(), could anyone tell me where i am going wrong ? being new to pdo im finding it a little confusing at the moment until i get my pdo book delivered to learn pdo. Thank you as always, phplover

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• Meaning of NEXT in Linked List creation in perl

  - by seleniumnewbie

  So I am trying to learn Linked Lists using Perl. I am reading "Mastering Algorithms with Perl" by Job Orwant. In the book he explains how to create a linked list I understand most of it, but I just simply fail to understand the command/index/key NEXT in the second last line of the code snippet. $list=undef; $tail=\$list; foreach (1..5){ my $node = [undef, $_ * $_]; $$tail = $node; $tail = \${$node->[NEXT]}; # The NEXT on this line? } What is he trying to do there? Isn $node a scalar, which stores the address of the unnamed array. Also even if we are de-referencing $node, should we not refer to the individual elements by an index number example (0,1). If we do use "NEXT" as a key, is $node a reference to a hash? I am very confused. Something in plain English will be highly appreciated.

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• Memcached getDelayed alternative implementation

  - by iBobo

  I would like to use getDelayed on the PHP Memcached extension but I think it's not implemented in the right way. Right now you ask for some keys and then retrieve all of them with fetch() and fetchAll(). But imagine a scenario where I need to retrieve 15 keys used in different parts of the page which I don't know in advance, but I can ask the various objects to give me the list. What I want is give the Memcached instance this list (each component would give its part) then later when I need them retrieve from the instance, but not all of them at once: each component would take the one it needs. Basically if I were to implement this I would prohibit using getDelayed alone and implement a bookGet($keys) method where you would add the keys to book (which actually calls getDelayed), and redefine get to handle these three cases: key is booked and retrieved - return the value; key is booked but not retrieved - go and force the fetch of the booked keys and return the correct value; key not booked - do a normal lookup. I want to know if this makes sense, your thoughts on the subject and if someone already implemented this or maybe PECL Memcached already works this way and actually the documentation doesn't explain it correctly.

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• Serializing a class containing a custom class

  - by Netfangled

  I want to serialize an object as xml that contains other custom classes. From what I understand (I've been reading MSDN and SO mostly), the XmlSerializer doesn't take this into account. This is the line that's confusing me: XML serialization serializes only the public fields and property values of an object into an XML stream. XML serialization does not include type information. For example, if you have a Book object that exists in the Library namespace, there is no guarantee that it will be deserialized into an object of the same type. Taken from MSDN, here For example, I want to serialize an object of type Order, but it contains a list of Products, and each one contains an object of type Category: class Order { List<Product> products; } class Product { Category type; } class Category { string name; string description; } And I want my Order object to be serialized like so: <Order> <Product> <Category Name=""> <Description></Description> </Category> </Product> <Product> <Category Name=""> <Description></Description> </Category> </Product> <Order> Does the XmlSerializer already do this? If not, is there another class that does or do I have to define the serialization process myself?

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• IS operator behaving a bit strangely

  - by flockofcode

  1) According to my book, IS operator can check whether expression E (E is type) can be converted to the target type only if E is either a reference conversion, boxing or unboxing. Since in the following example IS doesn’t check for either of the three types of conversion, the code shouldn’t work, but it does: int i=100; if (i is long) //returns true, indicating that conversion is possible l = i; 2) a) B b; A a = new A(); if (a is B) b = (B)a; int i = b.l; class A { public int l = 100; } class B:A { } The above code always causes compile time error “Use of unassigned variable”. If condition a is B evaluates to false, then b won’t be assigned a value, but if condition is true, then it will. And thus by allowing such a code compiler would have no way of knowing whether the usage of b in code following the if statement is valid or not ( due to not knowing whether a is b evaluates to true or false) , but why should it know that? Intsead why couldn’t runtime handle this? b) But if instead we’re dealing with non reference types, then compiler doesn’t complain, even though the code is identical.Why? int i = 100; long l; if (i is long) l = i; thank you

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• Reporting Services Sum of Inner Group in Outer Group

  - by Spoonybard

  I have a report in Reporting Services 2008 using ASP.net 3.5 and SQL Server 2008. The report has 2 groupings and a detail row. This is the current format: Outer Group Inner Group Detail Row The Detail Row represents an item on a receipt and a receipt can have multiple items. Each receipt was paid with a certain payment method. So the Outer Group is grouped by payment type, the Inner Group is grouped by the receipt's ID, and the Detail Row is each item for the given receipt. My raw data result set has two important columns: The Amount Received and the Amount Applied. The Amount Received is how much money in total was collected for all the items on the receipt. The Amount Applied is how much money each item got from the total Amount Received. Sample Result Set: ReceiptID Item ItemID AmountReceived AmountApplied Payment Method ------------------------------------------------------------------------------------------ 1 Book 1 $200.00 $40.00 Cash 1 CD 2 $200.00 $20.00 Cash 1 Software 3 $200.00 $100.00 Cash 1 Backpack 4 $200.00 $40.00 Cash The Inner Group displays the AmountReceived correctly as $200. However, the Outer Group displays the AmountReceived as $800, because I believe that it is going off each detail row which in this case is a count of 4 items. What I want is to see in the Outer Group that the Amount Received is $200. I tried restricting the scope in my SUM function to be the Inner Group, but I get the error "The scope parameter must be set to a string constant that is equal to either the name of a containing group, the name of a containing data region, or the name of a dataset." Does anyone have any suggestions on how to solve this issue? Thanks.

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• binary quicksort

  - by davit-datuashvili

  hi i want implement Binary quicksort algorithm from robert sedgewick book it looks like this public class quickb{ public static final int bitsword=32; public static void quicksortB(int a[],int l,int r,int d){ int i=l; int j=r-1; if (r<=l || d>bitsword) return ; while (j!=i) { while (digit(a[i],d)==0 && (i<j)) i++; while (digit(a[j],d)==1 && (j>i)) j++; int t=a[i]; a[i]=a[j]; a[j]=t; } if (digit(a[r-1],d)== 0) j++; quicksortB(a,l,j-1,d+1); quicksortB(a,j,r,d+1); } public static void main(String[]args){ int a[]=new int[]{4,7,3,9,8,2}; quicksortB(a,0,a.length-1,0); for (int i=0;i<a.length;i++){ System.out.println(a[i]); } } public static int digit(int m,int d){ return (m>>d)&1; } } but it show me error: java.lang.ArrayIndexOutOfBoundsException: 6 at quickb.quicksortB(quickb.java:13) at quickb.main(quickb.java:32) what is wrong?

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