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  • What makes my code DDD (domain-driven design) qualified?

    - by oykuo
    Hi All, I'm new to DDD and am thinking about using this design technique in my project. However, what strikes me about DDD is that how basic the idea is. Unlike other design techniques such as MVC and TDD, it doesn't seems to contain any ground breaking ideas. For example, I'm sure some of you will have the same feeling that the idea of root aggregates and repositories are nothing new because when you are was writing MVC web applications you have to have one single master object (i.e. the root aggregate) that contain other minor objects (i.e. value objects and entities) in the model layer in order to send data to a strongly typed view. To me, the only new idea in DDD is probably the "Smart" entities (i.e. you are supposed to have business rules on root aggregates) Separation between value object, root aggregate and entities. Can anyone tell me if I have missed out anything here? If that's all there is to DDD, if I update one of my existing MVC application with the above 2 new ideas, can I claim it's an TDD, MVC and DDD applcation?

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  • Flash automatically names objects on stage "instance#"

    - by meowMIX3R
    Hi, I have 2 TLF text boxes already placed on my main stage. In the property inspector window I give these the instance names: "txt1" and "txt2". I am trying to have a single mouseup event, and figure out which text box it occurred on. My document class has the following code: package { import flash.display.Sprite; import flash.events.KeyboardEvent; public class SingleEvent extends Sprite{ public function SingleEvent() { // constructor code root.addEventListener(KeyboardEvent.KEY_UP, textChanged,false,0,true); } private function textChanged(e:KeyboardEvent){ trace(e.target.name); trace(" " + e.target); switch(e.target){ case txt1: trace("txt1 is active"); break; case txt2: trace("txt2 is active"); break; default: break; } } } } Example output is: instance15 [object Sprite] instance21 [object Sprite] Since the objects are already on the stage, I am not sure how to get flash to recognize them as "txt1" and "txt2" instead of "instance#". I tried setting the .name property, but it had no effect. In the publish settings, I have "Automatically declare stage instances" checked. Also, is it possible to have a single change event for multiple slider components? The following never fires: root.addEventListener(SliderEvent.CHANGE, sliderChanged,false,0,true); Thanks for any tips

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  • servlet and jsp sending query result following MVC framework

    - by kawtousse
    Hi every one, in order to separate java code and html code and be more faithful to MVC framework i am coding like that; in the servlet i put the following: net.sf.hibernate.Session s = null; net.sf.hibernate.Transaction tx; try { s= HibernateUtil.currentSession(); tx=s.beginTransaction(); Query query = s.createQuery("select opcemployees.Nom,opcemployees.Prenom,dailytimesheet.TrackingDate,dailytimesheet.Activity," + "dailytimesheet.ProjectCode,dailytimesheet.WAName,dailytimesheet.TaskCode," + "dailytimesheet.TimeSpent,dailytimesheet.PercentTaskComplete from Opcemployees opcemployees,Dailytimesheet dailytimesheet " + "where opcemployees.Matricule=dailytimesheet.Matricule and dailytimesheet.Etat=3 " + "group by opcemployees.Nom,opcemployees.Prenom" ); for(Iterator it=query.iterate();it.hasNext();) { if(it.hasNext()){ Object[] row = (Object[]) it.next(); request.setAttribute("items", row); }} } catch (HibernateException e){ e.printStackTrace(); } request.getRequestDispatcher("EspaceValidation.jsp").forward(request, response); and in jsp i start like that: <table> <c:forEach items="${items}" var="item"> <tr> <td>? </td> <td>?</td> </tr> </c:forEach> in this case what should i put exactly to obtain my result.a table fulled with the right value from the request

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  • Parser Error Problem

    - by user177140
    Hi I have found a problem in Multilingual Asp.Net Web Application I have Created a Global.asax file and write the code private void Application_BeginRequest(Object source, EventArgs e) { string[] languages = HttpContext.Current.Request.UserLanguages; if (languages[0].ToLower() != null && languages[0].ToLower()!="") { System.Threading.Thread.CurrentThread.CurrentUICulture = new System.Globalization.CultureInfo(languages[0].ToLower()); System.Threading.Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.CreateSpecificCulture(languages[0].ToLower()); } } and define Label Like this <asp:Label ID="Labeldg" runat="server" Text="<%$ Resources:Resource, Labeldg %>"</asp:Label> But it through Parser error like: Parser Error Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately. Parser Error Message: The resource object with key 'LblUsrName_Login' was not found. Source Error: </div> <div class="impcLoginText_Login"> <asp:Label ID="LblUsrName" runat="server" Text="<%$ Resources:PageResource, LblUsrName_Login %>" "></asp:Label>

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  • Work with function references

    - by Ockonal
    Hello, I have another one question about functions reference. For example, I have such definition: typedef boost::function<bool (Entity &handle)> behaviorRef; std::map< std::string, ptr_vector<behaviorRef> > eventAssociation; The first question is: how to insert values into such map object? I tried: eventAssociation.insert(std::pair< std::string, ptr_vector<behaviorRef> >(eventType, ptr_vector<behaviorRef>(callback))); But the error: no matching function for call to ‘boost::ptr_vector<boost::function<bool(Entity&)> >::push_back(Entity::behaviorRef&)’ And I undersatnd it, but can't make workable code. The second question is how to call such functions? For example, I have one object of behaviorRef, how to call it with boost::bind with passing my own values?

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  • How costly performance-wise are these actions in iPhone objective-C?

    - by Alex Gosselin
    This is really a few questions in one, I'm wondering what the performance cost is for these things, as I haven't really been following a best practice of any sort for these. The answers may also be useful to other readers, if somebody knows these. (1) If I need the core data managed object context, is it bad to use #import "myAppDelegate.h" //farther down in the code: NSManagedObjectContext *context = [(myAppDelegate.h*)[[UIApplication sharedApplication] delegate] managedObjectContext]; as opposed to leaving the warning you get if you don't cast the delegate? (2) What is the cheapest way to hard-code a string? I have been using return @"myString"; on occasion in some functions where I need to pass it to a variety of places, is it better to do it this way: static NSString *str = @"myString"; return str; (3) How costly is it to subclass an object i wrote vs. making a new one, in general? (4) When I am using core data and navigating through a hierarchy of some sort, is it necessary to turn things back into faults somehow after I read some info from them? or is this done automatically? Thanks for any help.

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  • Is `super` local variable?

    - by Michael
    // A : Parent @implementation A -(id) init { // change self here then return it } @end A A *a = [[A alloc] init]; a. Just wondering, if self is a local variable or global? If it's local then what is the point of self = [super init] in init? I can successfully define some local variable and use like this, why would I need to assign it to self. -(id) init { id tmp = [super init]; if(tmp != nil) { //do stuff } return tmp; } b. If [super init] returns some other object instance and I have to overwrite self then I will not be able to access A's methods any more, since it will be completely new object? Am I right? c. super and self pointing to the same memory and the major difference between them is method lookup order. Am I right? sorry, don't have Mac to try, learning theory as for now...

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  • Hibernate Relationship Mapping/Speed up batch inserts

    - by manyxcxi
    I have 5 MySQL InnoDB tables: Test,InputInvoice,InputLine,OutputInvoice,OutputLine and each is mapped and functioning in Hibernate. I have played with using StatelessSession/Session, and JDBC batch size. I have removed any generator classes to let MySQL handle the id generation- but it is still performing quite slow. Each of those tables is represented in a java class, and mapped in hibernate accordingly. Currently when it comes time to write the data out, I loop through the objects and do a session.save(Object) or session.insert(Object) if I'm using StatelessSession. I also do a flush and clear (when using Session) when my line count reaches the max jdbc batch size (50). Would it be faster if I had these in a 'parent' class that held the objects and did a session.save(master) instead of each one? If I had them in a master/container class, how would I map that in hibernate to reflect the relationship? The container class wouldn't actually be a table of it's own, but a relationship all based on two indexes run_id (int) and line (int). Another direction would be: How do I get Hibernate to do a multi-row insert?

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  • Joomla User Login Question

    - by user277127
    I would like to enable users of my existing web app to login to Joomla with the credentials already stored in my web app's database. By using the Joomla 1.5 authentication plugin system -- http://docs.joomla.org/Tutorial:Creating_an_Authentication_Plugin_for_Joomla_1.5 -- I would like to bypass the Joomla registration process and bypass creating users in the Joomla database altogether. My thought had been that I could simply populate a User object, which would be stored in the Session, and that this would replace the need to store a user in the Joomla database. After looking through the code surrounding user management in Joomla, it seems like any time you interact with the User object, the database is being queried. It therefore seems like my initial idea won't work. Is that right? It looks like, in order to achieve the effect I want, I will have to actually register a user from within the authentication plugin at the time they first login. This is not ideal, so before I go forward with it, I wanted to check with Joomla developers whether it is possible to do what I described above. Thanks in advance -- I am new to Joomla and greatly appreciate your help!

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  • Get textboxes in to a list! c#

    - by Chelsea_cole
    public class Account { public string Username { get { return Username; } set { Username = value; } } } public class ListAcc { static void Data() { List<Account> UserList = new List<Account>(); //example of adding user account Account acc = new Account(); acc.Username = textBox1.Text; //error UserList.Add(acc); } } there are a error from access to textBox1.Text? ( An object reference is required for the nonstatic field, method, or property)... Someone can help? but if the code is: private void textBox1_TextChanged(object sender, EventArgs e) { List<Account> UserList = new List<Account>(); //example of adding user account Account acc = new Account(); acc.Username = textBox1.Text; UserList.Add(acc); } it's work! someone can help me fix my error? Many thanks!

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  • vb Syntax error in INSERT INTO statement

    - by user201806
    im new in vb, i was create a program to connection ms access but when i run the program it get syntax error in Insert into statement, OleDbExpection was unhandled here my code Public Class Form2 Dim cnn As New OleDb.OleDbConnection Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load txtdate.Value = DateTime.Now cnn = New OleDb.OleDbConnection cnn.ConnectionString = "Provider=Microsoft.Jet.Oledb.4.0; Data Source=C:\Users\John\Documents\db.mdb" End Sub Private Sub btnsave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnsave.Click If Not cnn.State = ConnectionState.Open Then cnn.Open() End If Dim cmd As New OleDb.OleDbCommand cmd.Connection = cnn cmd.CommandText = "INSERT INTO sr(names,add,tel,dates,prob,serv,model,snm,acc,sna,remark)" & _ "VALUES ('" & Me.txtname.Text & "','" & Me.txtadd.Text & "','" & Me.txttel.Text & "', '" & _ Me.txtdate.Text & "','" & Me.txtpro.Text & "','" & Me.txtser.Text & "','" & Me.txtmod.Text & "', '" & _ Me.txtsnm.Text & "','" & Me.txtacc.Text & "','" & Me.txtsna.Text & "','" & Me.txtrem.Text & "')" cmd.ExecuteNonQuery() cnn.Close() End Sub End Class it's there any wrong with my code?

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  • Code producing System.NullReferenceException error for Membership.GetUser(). This is VB.Net (ASP.Net 4)

    - by Derrek
    I have a Default.aspx page that is not static. I have added functionality with datalist and sqldatasources. When a user logins he/she will see items like saved workouts, saved equipment, total replys, etc... This is based on getting the currently logged in user UserID. Quite simply this works great when the user is logged in. However, I do not want to force a user to login to view the Default page because it does have functionality on it that does not require login. When a user is not logged in of course I receive the [System.NullReferenceException] error. I understand the error well but I do not know how to code to fix it. That is where I need help. I will admit I am more designer than developer. However, I do know the exception error I am receivving is caused by me not setting a value in my code when a user is not logged in. I do not know how to do that and have for a week made unsuccessful attempts at writing the code. Both sets of code below compile for VB.Net/ASP.Net 4/Visual Studio 2010 without errors. However, I still get the System.NullReferenceException error if not logged in. I know it can be done but I do not know the right syntax. If you can help please insert you code in mine or write it out. JUST TELLING ME WHERE TO GO TO FIND AN ANSWER WON'T HELP. I HAVE DONE THAT FOR 7 STRAIGHT DAYS. I APPRECIATE OUR HELP. Partial Class _Default Inherits System.Web.UI.Page Protected Sub SqlDataSource4_Selecting(ByVal sender As Object, ByVal e As SqlDataSourceCommandEventArgs) Handles SqlDataSource4.Selecting Dim MemUser As MembershipUser MemUser = Membership.GetUser() If Not MemUser Is DBNull.Value Then UserID.Text = MemUser.ProviderUserKey.ToString() e.Command.Parameters("@UserId").Value = MemUser.ProviderUserKey.ToString() End If End Sub -------------------------------------ORIGINAL CODE------------------------------- Partial Class _Default Inherits System.Web.UI.Page Protected Sub SqlDataSource4_Selecting(ByVal sender As Object, ByVal e As SqlDataSourceCommandEventArgs) Handles SqlDataSource4.Selecting Dim MemUser As MembershipUser MemUser = Membership.GetUser() UserID.Text = MemUser.ProviderUserKey.ToString() e.Command.Parameters("@UserId").Value = MemUser.ProviderUserKey.ToString() End Sub

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  • HTML5 card game [closed]

    - by ChrisCa
    I created a card game in silverlight a year or so ago in order to learn a bit about Silverlight. I am now wanting to make a HTML5 version of the game in an effort to learn a little bit more about that. I am thinking I'd like to take advantage of stuff like Knockout.js and WebSockets and the canvas element. Now what I'm confused about is how to lay out the cards on the screen. With Silverlight I was able to make a "Hand" control, which was made up of two sub controls - the cards the player has in their hand and the ones they have on the table. And they in turn were made up of Card controls. Now I don't believe there is the concept on a User Control in javascript. So I am possibly thinking about this in entirely the wrong way. So my question is - how could I lay out some cards on the table and perhaps make reuse of something for each player? I have a client side JSON object called game, which contains an array of players. Each player has a hand which is made up of an array of in-hand cards and on-table cards. Ideally I would like to bind these to something using Knockout.js - but I don't know what I could bind to. Would I simply position images (of cards) on a canvas? Is there a way to make some kind of Hand object that each player could have and that I could bind to? Any advice? Or sample code you've seen elsewhere?

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  • Question about singleton property

    - by Jack
    I'm reading the java tutorial for enums located here and have a question: http://java.sun.com/j2se/1.5.0/docs/guide/language/enums.html#Card The part i'm confused about is as follows: "The Card class, above, contains a static factory that returns a deck, but there is no way to get an individual card from its rank and suit. Merely exposing the constructor would destroy the singleton property (that only a single instance of each card is allowed to exist). Here is how to write a static factory that preserves the singleton property, using a nested EnumMap: " Now as I understand, changing the original private "Card" constructor to public would allow us to instantiate an unlimited number of copies of a "Card" object with a given suit+rank. The solution as proposed was to create an EnumMap which would store four Maps (one for each suit), which themselves contained 13 Card objects with the rank as their keys. And so now if you wanted to retrieve a specific Card object from the deck, you would just call the "valueOf" method. My question now is, what's the prevent you with calling the valueOf method as many times as you like? Wouldn't that lead to the same problem as making the original private constructor public? Thanks.

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  • How to enforce jsf to create new instance of bean instead of throwing NullPointerException?

    - by Roman
    I'm almost sure that I do something wrong and thus the question's title is a bit incorrect. I have a form with several fields for creating a new User-objects (fields like login, password, birthday etc). And I have 2 buttons - Cancel and Create. I didn't finish Create yet :) , but when I press Cancel I see NullPointerException. Here is simplified code: <f:view> <h:form> <h:panelGroup layout="block"> <h:inputText id="add_login" value="#{userSupport.user.login}"/> <h:inputSecret id="add_password" value="#{userSupport.user.password}"/> <h:inputText id="add_name" value="#{userSupport.user.name}"/> <h:inputText id="add_surname" value="#{userSupport.user.surname}"/> <h:commandButton value="Cancel" action="cancel"/> </h:panelGroup> </h:form> </f:view> UserSupport class has field user with getter and setter and some other methods. It's a Spring bean with Session scope. When I press cancel, I see NPE because jsf tries to save values from inputs in user-object, but user-object is null. What is the correct way of doing this?

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  • Complicated API issue with calling assemblies dynamically?

    - by Stefanos Tses
    I have an interesting challenge that I'm wondering if anyone here can give me some direction. I'm writing a .Net windows forms application that runs on a network and uses an SQL Server to save and pull data. I want to offer a mini "plugin" API, where developers can build their own assemblies and implement a specific interface (IDataManipulate). These assemblies then can be used by my application to call the interface functions and do something. I can create assemblies using my API, copy the file to a folder in my local hard drive and configure my application to use Reflection to call a specific function from the implemented interface (IDataManipulate.Execute). The problem: Since the application will be installed in multiple workstations in the network, is impossible to copy the plugin dlls the users will create to each machine. Solutions I tried: Solution 1 Copy the API dll to a network share. Problem: Requires AllowPartiallyTrustedCallersAttribute, which requires .Net singing, which I can't force from my users. Solution 2 (preferred) Serialize the dll object, save it to the database, deserialize it and call IDataManipulate.Execute. Problem: After deserialization, I try cast it to a IDataManipulate object but returns an error looking for the actual dll file. Solution 3 Save the dll bytes as byte[] to the database and recreate the dll at the local PC every time the user starts my application. Problem: Dll may have dependencies, which I don't know if I can detect. Any suggestions will be greatly appreciated. Thanks

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  • Trouble defining method for Javascript class definition.

    - by btoverdrive
    I'm somewhat new to object oriented programming in Javascript and I'm trying to build a handler object and library for a list of items I get back from an API call. Ideally, I'd like the library functions to be members of the handler class. I'm having trouble getting my class method to work however. I defined as part of the class bcObject the method getModifiedDateTime, but when I try to echo the result of the objects call to this method, I get this error: Error on line 44 position 26: Expected ';' this.getModifiedDateTime: function(epochtime) { which leads me to believe that I simply have a syntax issue with my method definition but I can't figure out where. response( { "items": [ {"id":711,"name":"Shuttle","lastModifiedDate":"1268426336727"}, {"id":754,"name":"Formula1","lastModifiedDate":"1270121717721"} ], "extraListItemsAttr1":"blah", "extraListItemsAttr2":"blah2" }); function response(MyObject) { bcObject = new bcObject(MyObject); thing = bcObject.getModifiedDateTime(bcObject.videoItem[0].lastModifiedDate); SOSE.Echo(thing); } function bcObject(listObject) { // define class members this.responseList = {}; this.videoCount = 0; this.videoItem = []; this.responseListError = ""; // instantiate members this.responseList = listObject; this.videoCount = listObject.items.length; // populate videoItem array for (i=0;i<this.videoCount;i++) { this.videoItem[i] = listObject.items[i]; } this.getModifiedDateTime: function(epochtime) { var dateStringOutput = ""; var myDate = new Date(epochtime); dateStringOutput = myDate.toLocaleString(); return dateStringOutput; }; }

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  • Retrieving values from a table in HTML using jQuery?

    - by Mo
    Hi i was just wondering whats the best way to retrieve the following labels and values from this HTMl code using jquery and storing them in to a array or hash map of some sort where i have for e.g "DataSet:" : "prod" or ["Dataset", "Prod"]? <table id="metric_summary"> <tbody> <tr class="editable_metrics"> <td><label>DataSet:</label></td> <td><input name="DataSet" value="prod"></td> </tr> <tr class="editable_metrics"> <td><label>HostGroup:</label></td> <td><input name="HostGroup" value="MONITOR-PORTAL-IAD"></td> </tr> <tr class="editable_metrics"> <td><label>Host:</label></td> <td><input name="Host" value="ALL"></td> </tr> <tr class="editable_metrics"> <td><label>Class:</label></td> <td><input name="Class" value="CPU"></td> </tr> <tr class="editable_metrics"> <td><label>Object:</label></td> <td><input name="Object" value="cpu"></td> </tr> <tr class="editable_metrics"> <td><label>Metric:</label></td> <td><input name="Metric" value="CapacityCPUUtilization"></td> </tr> thanks

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  • How to create a class by reading from another class (.cs) file with Powershell?

    - by Razcer
    I have this POGO ( simple putter getter) class that I am trying to read in PowerShell using System; using System.Runtime.Serialization; namespace MyApp.VM { [Serializable] public class MyClassVM { public Int64 CtrId { get; set; } public string CtrName { get; set; } public string CtrPhone { get; set; } public string CtrZip { get; set; } public DateTime AddDate { get; set; } } } Here is the ps1 code that is trying to read the class from a file. function Build-Pogo { $FileDir = "D:\YourDirectoryOfPogo" $ClassName = "MyClassVM" $FileName = $FileDir + "\" + $ClassName + ".cs" # Build the class from the file $AllLines = [string]::join([environment]::newline, (Get-Content $FileName)) Add-Type -TypeDefinition $AllLines # spin thru each property for class $ClassHandle = New-Object -typeName $ClassName $ClassHandle | ForEach-Object {Write-Host $_.name -foregroundcolor cyan} } *Note the last line is placeholder for more complex logic to come later. This breaks at the Add-Type with this error message for each get/set in the file. 'MyApp.VM.MyClassVM.CtrId.get' must declare a body because it is not marked abstract or extern Any info on what I'm doing wrong will be greatly appreciated.

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  • Rails - Beginner wants feedback on how they've modeled their app and how to do it better.

    - by adam
    I think the way I've modelled my app is a bit fishy and i need to rejig things, im just not sure how. I've already re-jigged and refactored before. It took a long time ( I'm a beginner ) and I'm hesitant to it again in case i head off in the wrong direction again. Basic Idea, user can submit an answer, another user can mark it correct or incorrect. If incorrect they have to write the correct answer. Users can view their and everybody else's correct and incorrect answers. So I did it this way class Answer has_one: correction end class Correction belongs_to :answer end when a user marks an answer as correct, I set checked_at:DateTime and checked_by_id:integer on the Answer object to keep track of who checked the answer and when. For incorrect answers I create a correction object which holds the correct answer and again checked_by and checked_at details. I don't like this because I have checked_by and checked_at in both models. It just doesn't sit right. Possible solutions are: Create a third model such as VerifiedAnswer and move the checked_by/at attributes to that. It will handle the situtation where an answer is marked correct. Or are these models thin enough (they dont have any other attributes) that I can just have one model ( Answer ) that has all the attributes to store all this information?

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  • Is CDS a valid analogy for pointers? [closed]

    - by Flinkman
    So.. bear with me. I just found an analogy to c++ pointers and CDS. This clip describes CDS(Credit Default Swaps). http://www.youtube.com/watch?v=KPNdYtrlgaU#t=120s "Here we know we have an instrument of a particular financial instrument that is demonstrably dangerous, it creates long chains of risk which are vulnerable to the failure of individual trader or market partipants, in that chain and these instruments in an affect permit the creation of vicious spirals. In which the CDS price interact with the bound price, the market price and you can have a downward spiral." What my ears are telling me: "Don't create dependences that will create long chains of crashing systems." Update: Trying to clarify with something that is closer to the readers. If I change the words: instrument = construct financial = language trader = object market partipants = c structs CDS price = uptime bound price = outcome market price = ROI(return on incestment) The quote become more understandable. Look: "Here we know we have construct of a particular language construct that is demonstrably dangerous, it creates long chains of risk which are vulnerable to the failure of individual object or structs in that chain and these system in an affect permit the creation of vicious spirals. In which the uptime interact with the outcome, the ROI and you can have a downward spiral."

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  • Is it okay to violate the principle that collection properties should be readonly for performance?

    - by uriDium
    I used FxCop to analyze some code I had written. I had exposed a collection via a setter. I understand why this is not good. Changing the backing store when I don't expect it is a very bad idea. Here is my problem though. I retrieve a list of business objects from a Data Access Object. I then need to add that collection to another business class and I was doing it with the setter method. The reason I did this was that it is going to be faster to make an assignment than to insert hundreds of thousands of objects one at a time to the collection again via another addElement method. Is it okay to have a getter for a collection in some scenarios? I though of rather having a constructor which takes a collection? I thought maybe I could pass the object in to the Dao and let the Dao populate it directly? Are there any other better ideas?

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  • How do I make this Java code operate properly? [Multi-threaded, race condition]

    - by Fixee
    I got this code from a student, and it does not work properly because of a race condition involving x++ and x--. He added synchronized to the run() method trying to get rid of this bug, but obviously this only excludes threads from entering run() on the same object (which was never a problem in the first place) but doesn't prevent independent objects from updating the same static variable x at the same time. public class DataRace implements Runnable { static volatile int x; public synchronized void run() { for (int i = 0; i < 10000; i++) { x++; x--; } } public static void main(String[] args) throws Exception { Thread [] threads = new Thread[100]; for (int i = 0; i < threads.length; i++) threads[i] = new Thread(new DataRace()); for (int i = 0; i < threads.length; i++) threads[i].start(); for (int i = 0; i < threads.length; i++) threads[i].join(); System.out.println(x); // x not always 0! } } Since we cannot synchronize on x (because it is primitive), the best solution I can think of is to create a new static object like static String lock = ""; and enclose the x++ and x-- within a synchronized block, locking on lock. But this seems really awkward. Is there a better way?

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  • help with basic MVC project

    - by Shrewd Demon
    hi, i am creating a demo MVC project and i am getting a Null Object Reference error for the following code. <% foreach (var item in Model) { %> <tr> <td> <%= Html.ActionLink("Edit", "Edit", new { /* id=item.PrimaryKey */ }) %> | <%= Html.ActionLink("Details", "Details", new { /* id=item.PrimaryKey */ })%> | <%= Html.ActionLink("Delete", "Delete", new { /* id=item.PrimaryKey */ })%> </td> <td> <%= Html.Encode(item.ContactEmail) %> </td> <td> <%= Html.Encode(item.YourQuery) %> </td> </tr> <% } %> i get an error in the first line itself (var item in Model) coz i am getting the Model object as null. Can anyone please help me. thanks.

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  • How do disable Rails submit buttons alongside Prototype helpers & RJS?

    - by Jesse
    I'm trying to follow this post http://stackoverflow.com/questions/576240/how-can-i-unobtrusively-disable-submit-buttons-with-javascript-and-prototype but I can't get it to work. The form triggers an RJS function, so I need to keep the helpers' onclick events intact. The RJS returns/reloads the same forms along with two new texts. I'm really confused. Here is my rails code for the forms: .span-20#comparison / new comparison . . . / voting forms (also reloaded) .span-4.prepend-3.append-6 - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 1 = submit_tag "Vote for me", :disabled => false, :disable_with => 'Vote for me', :class => "compare" .span-4.append-3.last - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 2 = submit_tag "Vote for me", :disable_with => 'Vote for me', :class => "compare" .span-4.prepend-8.append-8.prepend-top.last - form_remote_tag :action => url_for(:controller => :comparisons), :method => :post do = hidden_field_tag :poem1_id, poems[:a].id = hidden_field_tag :poem2_id, poems[:b].id = hidden_field_tag :response, 'draw' = submit_tag "Declare Draw", :disable_with => 'Declare Draw', :class => "compare" RJS page.replace_html :comparison, :partial => 'poems', :object => @poems page.insert_html :top, :previous, :partial => 'comparison', :object => @comparison page << "Effect.ScrollTo($('top'));"

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