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  • many-to-many performance concerns with fluent nhibernate.

    - by Ciel
    I have a situation where I have several many-to-many associations. In the upwards of 12 to 15. Reading around I've seen that it's generally believed that many-to-many associations are not 'typical', yet they are the only way I have been able to create the associations appropriate for my case, so I'm not sure how to optimize any further. Here is my basic scenario. class Page { IList<Tag> Tags { get; set; } IList<Modification> Modifications { get; set; } IList<Aspect> Aspects { get; set; } } This is one of my 'core' classes, and coincidentally one of my core tables. Virtually half of the objects in my code can have an IList<Page>, and some of them have IList<T> where T has its own IList<Page>. As you can see, from an object oriented standpoint, this is not really a problem. But from a database standpoint this begins to introduce a lot of junction tables. So far it has worked fine for me, but I am wondering if anyone has any ideas on how I could improve on this structure. I've spent a long time thinking and in order to achieve the appropriate level of association required, I cannot think of any way to improve it. The only thing I have come up with is to make intermediate classes for each object that has an IList<Page>, but that doesn't really do anything that the HasManyToMany does not already do except introduce another class. It does not extend the functionality and, from what I can tell, it does not improve performance. Any thoughts? I am also concerned about Primary Key limits in this scenario. Most everything needs to be able to have these properties, but the Pages cannot be unique to each object, because they are going to be frequently shared and joined between multiple objects. All relationships are one-sided. (That is, a Page has no knowledge of what owns it). Because of this, I also have no Inverse() mapped HasManyToMany collections. Also, I have read the similar question : Usage of ORMs like NHibernate when there are many associations - performance concerns But it really did not answer my concerns.

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  • Mysterious constraints problem with SQL Server 2000

    - by Ramon
    Hi all I'm getting the following error from a VB NET web application written in VS 2003, on framework 1.1. The web app is running on Windows Server 2000, IIS 5, and is reading from a SQL server 2000 database running on the same machine. System.Data.ConstraintException: Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints. at System.Data.DataSet.FailedEnableConstraints() at System.Data.DataSet.EnableConstraints() at System.Data.DataSet.set_EnforceConstraints(Boolean value) at System.Data.DataTable.EndLoadData() at System.Data.Common.DbDataAdapter.FillFromReader(Object data, String srcTable, IDataReader dataReader, Int32 startRecord, Int32 maxRecords, DataColumn parentChapterColumn, Object parentChapterValue) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, String srcTable, IDataReader dataReader, Int32 startRecord, Int32 maxRecords) at System.Data.Common.DbDataAdapter.FillFromCommand(Object data, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet, Int32 startRecord, Int32 maxRecords, String srcTable, IDbCommand command, CommandBehavior behavior) at System.Data.Common.DbDataAdapter.Fill(DataSet dataSet) The problem appears when the web app is under a high load. The system runs fine when volume is low, but when the number of requests becomes high, the system starts rejecting incoming requests with the above exception message. Once the problem appears, very few requests actually make it through and get processed normally, about 2 in every 30. The vast majority of requests fail, until a SQL Server restart or IIS reset is performed. The system then start processing requests normally, and after some time it starts throwing the same error. The error occurs when a data adapter runs the Fill() method against a SELECT statement, to populate a strongly-typed dataset. It appears that the dataset does not like the data it is given and throws this exception. This error occurs on various SELECT statements, acting on different tables. I have regenerated the dataset and checked the relevant constraints, as well as the table from which the data is read. Both the dataset definition and the data in the table are fine. Admittedly, the hardware running both the web app and SQL Server 2000 is seriously outdated, considering the numbers of incoming requests it currently receives. The amount of RAM consumed by SQL Server is dynamically allocated, and at peak times SQL Server can consume up to 2.8 GB out of a total of 3.5 GB on the server. At first I suspected some sort of index or database corruption, but after running DBCC CHECKDB, no errors were found in the database. So now I'm wondering whether this error is a result of the hardware limitations of the system. Is it possible for SQL Server to somehow mess up the data it's supposed to pass to the dataset, resulting in constraint violation due to, say, data type/length mismatch? I tried accessing the RowError messages of the data rows in the retrieved dataset tables but I kept getting empty strings. I know that HasErrors = true for the datatables in question. I have not set the EnableConstraints = false, and I don't want to do that. Thanks in advance. Ray

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  • Adding two different Objects by overloading operator+ C++

    - by lampshade
    Hello, I've been trying to figure out how to add a private member from Object A, to a private member from Object B. Both Cat and Dog Class's inheriate from the base class Animal. I have a thrid class 'MyClass', that I want to inheriate the private members of the Cat and Dog class. So in MyClass, I have a friend function to overload the + operator. THe friend function is defined as follows: MyClass operator+(const Dog &dObj, const Cat &cObj); I want to access dObj.age and cObj.age within the above function, invoke by this statement in main: mObj = dObj + cObj; Here is the entire source for a complete reference into the class objects: #include <iostream> #include <vld.h> using namespace std; class Animal { public : Animal() {}; virtual void eat() = 0 {}; virtual void walk() = 0 {}; }; class Dog : public Animal { public : Dog(const char * name, const char * gender, int age); Dog() : name(NULL), gender(NULL), age(0) {}; virtual ~Dog(); void eat(); void bark(); void walk(); private : char * name; char * gender; int age; }; class Cat : public Animal { public : Cat(const char * name, const char * gender, int age); Cat() : name(NULL), gender(NULL), age(0) {}; virtual ~Cat(); void eat(); void meow(); void walk(); private : char * name; char * gender; int age; }; class MyClass : private Cat, private Dog { public : MyClass() : action(NULL) {}; void setInstance(Animal &newInstance); void doSomething(); friend MyClass operator+(const Dog &dObj, const Cat &cObj); private : Animal * action; }; Cat::Cat(const char * name, const char * gender, int age) : name(new char[strlen(name)+1]), gender(new char[strlen(gender)+1]), age(age) { if (name) { size_t length = strlen(name) +1; strcpy_s(this->name, length, name); } else name = NULL; if (gender) { size_t length = strlen(gender) +1; strcpy_s(this->gender, length, gender); } else gender = NULL; if (age) { this->age = age; } } Cat::~Cat() { delete name; delete gender; age = 0; } void Cat::walk() { cout << name << " is walking now.. " << endl; } void Cat::eat() { cout << name << " is eating now.. " << endl; } void Cat::meow() { cout << name << " says meow.. " << endl; } Dog::Dog(const char * name, const char * gender, int age) : name(new char[strlen(name)+1]), gender(new char[strlen(gender)+1]), age(age) { if (name) { size_t length = strlen(name) +1; strcpy_s(this->name, length, name); } else name = NULL; if (gender) { size_t length = strlen(gender) +1; strcpy_s(this->gender, length, gender); } else gender = NULL; if (age) { this->age = age; } } Dog::~Dog() { delete name; delete gender; age = 0; } void Dog::eat() { cout << name << " is eating now.. " << endl; } void Dog::bark() { cout << name << " says woof.. " << endl; } void Dog::walk() { cout << name << " is walking now.." << endl; } void MyClass::setInstance(Animal &newInstance) { action = &newInstance; } void MyClass::doSomething() { action->walk(); action->eat(); } MyClass operator+(const Dog &dObj, const Cat &cObj) { MyClass A; //dObj.age; //cObj.age; return A; } int main() { MyClass mObj; Dog dObj("B", "Male", 4); Cat cObj("C", "Female", 5); mObj.setInstance(dObj); // set the instance specific to the object. mObj.doSomething(); // something happens based on which object is passed in dObj.bark(); mObj.setInstance(cObj); mObj.doSomething(); cObj.meow(); mObj = dObj + cObj; return 0; }

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  • PHP Serialization Will not work correctly.

    - by stevoo
    Hi, I am developing and doing all the testing on a local machine using PHP Version 5.3.3-1ubuntu9.1 version. The host machine is PHP Version 5.2.15. All the seriliaze arguments are identical. The problems is when i try to login the user on my test local machine i do the following : $user->getByUserId($results['id'],$db); $_SESSION['user'] = serialize($user); which retrieved me and serialize the user. and i just load it back when ever i detect that a session exists $user->LoadFromObject(unserialize($_SESSION['user'])); This works perfectly on my test machine. Just transfered the files on the host to see if i can get a beta version out but i keep on getting Warning: unserialize() expects parameter 1 to be string, object given in /home/gamerent/public_html/beta/includes/header.php on line 19 i have noticed that if i echo the $_SESSION['user'] in both system the test will indeed display me the serializated one but the main one will just show me the object and will not serialize the $user

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  • Synclock a section of code while waiting for ShowDialog to return

    - by clawson
    I'm having trouble working out how to lock my application out of a section of code while it waits for a response from an external program. I've used Synclock on a section of code with the Me object in the expression. In this Synclock I call an overridden ShowDialog method of a dialog box, which has a timeout parameter, but does return the value from the underlying ShowDialog function call ,once the timer is setup. Works like this. SyncLock Me Dim frmDlgWithTimeout As New frmDlgWithTimeout ' dialog box with overridden ShowDialog ' Dim res As DialogResult = frmDlgWithTimeout.ShowDialog(10 * 1000) ' 10 sec timeout ' End SyncLock Now, external programs may raise events that bring my application to this Synclock but it doesn't prevent it from entering it, even though the ShowDialog function hasn't returned a value (and hence what I thought would keep the section of code locked). There is only one instance of the object that is used for lock in the program. Your help is greatly appreciated.

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  • Concatenating databases with Squeryl

    - by Pengin
    I'm trying to use Squeryl to take the contents of a table from one database, and append it to the equivalent table in another database. The primary key will have to be reassigned in the process, but I'm getting the error NULL not allowed for column "SIMID". Why is this? object Concatenator { def main(args: Array[String]) { Class.forName("org.h2.Driver"); val seshA = Session.create( java.sql.DriverManager.getConnection("jdbc:h2:file:data/resultsA", "sa", "password"), new H2Adapter ) val seshB = Session.create( java.sql.DriverManager.getConnection("jdbc:h2:file:data/resultsB", "sa", "password"), new H2Adapter ) using(seshA){ import Library._ from(sims){s => select(s)}.foreach{item => using(seshB){ sims.insert(item); } } } } case class Simulation( @Column("SIMID") var id: Long, val date: Date ) extends KeyedEntity[Long] object Library extends Schema { val sims = table[Simulation] on(sims)(s => declare( s.id is(unique, indexed, autoIncremented) )) } }

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  • Does Ruby on Rails "has_many" array provide data on a "need to know" basis?

    - by Jian Lin
    On Ruby on Rails, say, if the Actor model object is Tom Hanks, and the "has_many" fans is 20,000 Fan objects, then actor.fans gives an Array with 20,000 elements. Probably, the elements are not pre-populated with values? Otherwise, getting each Actor object from the DB can be extremely time consuming. So it is on a "need to know" basis? So does it pull data when I access actor.fans[500], and pull data when I access actor.fans[0]? If it jumps from each record to record, then it won't be able to optimize performance by doing sequential read, which can be faster on the hard disk because those records could be in the nearby sector / platter layer -- for example, if the program touches 2 random elements, then it will be faster just to read those 2 records, but what if it touches all elements in random order, then it may be faster just to read all records in a sequential way, and then process the random elements. But how will RoR know whether I am doing only a few random elements or all elements in random?

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  • Keyboard event issue

    - by Petar Minchev
    Hello guys! I have to capture the following keyboard event in a TextBox - SHIFT + 8(on the numpad). This also means the NumLock will be on. When I try the following, nothing is printed: private void textBox1_KeyDown(object sender, KeyEventArgs e) { if (e.Shift && e.KeyCode == Keys.NumPad8) Console.WriteLine("SHIFT + UP"); } But CTRL + 8(on the numpad) is working. private void textBox1_KeyDown(object sender, KeyEventArgs e) { if (e.Control && e.KeyCode == Keys.NumPad8) Console.WriteLine("CTRL + UP"); } Could someone explain me, why SHIFT + 8 isn't fired, but CTRL + 8 is working? P.S. I wrote + UP, because the user wants to navigate with the numpad arrows and the SHIFT key, but his NumLock will also be on. That's why I catch Keys.NumPad8. All the best, Petar

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  • Should I use the ref or out keyword here?

    - by Blankman
    I have an object that may be null, which I will pass to a method that will set its properties. So my code looks like: User user = null; // may or may not be null at this point. SetUserProperties(user); UpdateUser(user); public void SetUserProperties(User user) { if(user == null) user = new User(); user.Firstname = "blah"; .... } So I am updating the same object I pass into SetUserProperties. Should I use the 'ref' keyword in my method SetUserProperties?

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  • Shutting down a WPF application from App.xaml.cs

    - by Johannes Rössel
    I am currently writing a WPF application which does command-line argument handling in App.xaml.cs (which is necessary because the Startup event seems to be the recommended way of getting at those arguments). Based on the arguments I want to exit the program at that point already which, as far as I know, should be done in WPF with Application.Current.Shutdown() or in this case (as I am in the current application object) probably also just this.Shutdown(). The only problem is that this doesn't seem to work right. I've stepped through with the debugger and code after the Shutdown() line still gets executed which leads to errors afterwards in the method, since I expected the application not to live that long. Also the main window (declared in the StartupUri attribute in XAML) still gets loaded. I've checked the documentation of that method and found nothing in the remarks that tell me that I shouldn't use it during Application.Startup or Application at all. So, what is the right way to exit the program at that point, i. e. the Startup event handler in an Application object?

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  • Castle ActiveRecord: session error search and access to lazy loading property in different threads

    - by sc911
    Hi *, I've got a problem with an multi-threaded desktop application using Castle ActiveRecord in C#: To keep the GUI alive while searching for the objects based on userinput I'm using the BackgroundWorker for the search-function. Some of the properties of the objects, especially some HasMany-Relations, are marked as Lazy. Now, when the search is finished and the user selects an resulting object, some of the properties of this object should be displayed. But as the search was done by the BackgroundWorker in a different thread, accessing the properties fails as the session for the lazy-access is no longer available. What will be the best way to do the search in an extra thread to keep the GUI alive and to access all properties correctly including those marked as lazy? Thanks for any advise! Regards sc911

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  • redirect an event in VB.NET

    - by serhio
    I havea a UserControl1 (in witch I have an Label1) in Form1. I want to catch the MouseDown event from label and send it like from UserControl I do: Public Class UserControl1 Shadows Custom Event MouseDown As MouseEventHandler AddHandler(ByVal value As MouseEventHandler) AddHandler Label1.MouseDown, value End AddHandler RemoveHandler(ByVal value As MouseEventHandler) RemoveHandler Label1.MouseDown, value End RemoveHandler RaiseEvent(ByVal sender As Object, ByVal e As MouseEventArgs) 'RaiseMouseEvent(Me, e) ??? ' End RaiseEvent End Event End Class However, when I set in the Form1 the UserControl Private Sub UserControl11_MouseDown(ByVal sender As System.Object, _ ByVal e As System.Windows.Forms.MouseEventArgs) _ Handles UserControl11.MouseDown MessageBox.Show(sender.GetType.Name) 'here I have 'Label', want 'UserControl' End Sub

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  • How to inject a "runtime" dependency like a logged in user which is not available at application boot time?

    - by Fabian
    I'm just not getting this: I use Gin in my java GWT app to do DI. The login screen is integrated into the full application window. After the user has logged in I want to inject the user object into other classes like GUI Presenters which I create, so I have some sort of runtime dependency I believe. How do i do that? One solution I can think of is sth like: class Presenter { @Inject Presenter(LoggedInUserFactory userFactory) { User user = userFactory.getLoggedInUser(); } } class LoggedInUserFactoryImpl { public static User user; User getLoggedInUser() { return user; } } So, when the user is successfully logged in and I have the object i set the static property in LoggedInUserFactory, but this will only work if the Presenter is created after the user has logged in which is not the case. Or should I use a global static registry? I just don't like the idea of having static dependencies in my classes. Any input is greatly appreciated.

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  • Cached ObjectDataSource not firing Select Event even Cache Dependecy Removed

    - by John Polvora
    I have the following scenario. A Page with a DetailsView binded to an ObjectDatasource with cache-enabled. The SelectMethod is assigned at Page_Load event, depending on my User Level Logic. After assigned the selectMethod and Parameters for the ODS, if Cache not exists, then ODS will be cached the first time. The next time, the cache will be applied to the ODS and the select event don't need to be fired since the dataresult is cached. The problem is, the ODS Cache works fine, but I have a Refresh button to clear the cache and rebind the DetailsView. Am I doing correctly ? Below is my code. <asp:DetailsView ID="DetailsView1" runat="server" DataSourceID="ObjectDataSource_Summary" EnableModelValidation="True" EnableViewState="False" ForeColor="#333333" GridLines="None"> </asp:DetailsView> <asp:ObjectDataSource ID="ObjectDataSource_Summary" runat="server" SelectMethod="" TypeName="BL.BusinessLogic" EnableCaching="true"> <SelectParameters> <asp:Parameter Name="idCompany" Type="String" /> <SelectParameters> </asp:ObjectDataSource> <asp:ImageButton ID="ImageButton_Refresh" runat="server" OnClick="RefreshClick" ImageUrl="~/img/refresh.png" /> And here is the code behind public partial class Index : Page { protected void Page_Load(object sender, EventArgs e) { ObjectDataSource_Summary.SelectMethod = ""; ObjectDataSource_Summary.SelectParameters[0].DefaultValue = ""; switch (this._loginData.UserLevel) //this is a struct I use for control permissions e pages behaviour { case OperNivel.SysAdmin: case OperNivel.SysOperator: { ObjectDataSource_Summary.SelectMethod = "SystemSummary"; ObjectDataSource_Summary.SelectParameters[0].DefaultValue = "0"; break; } case OperNivel.CompanyAdmin: case OperNivel.CompanyOperator: { ObjectDataSource_Summary.SelectMethod = "CompanySummary"; ObjectDataSource_Summary.SelectParameters[0].DefaultValue = this._loginData.UserLevel.ToString(); break; } default: break; } } protected void Page_LoadComplete(object sender, EventArgs e) { if (Cache[ObjectDataSource_Summary.CacheKeyDependency] == null) { this._loginData.LoginDatetime = DateTime.Now; Session["loginData"] = _loginData; Cache[ObjectDataSource_Summary.CacheKeyDependency] = _loginData; DetailsView1.DataBind(); } } protected void RefreshClick(object sender, ImageClickEventArgs e) { Cache.Remove(ObjectDataSource_Summary.CacheKeyDependency); } } Can anyone help me? The Select() Event of the ObjectDasource is not firing even I Remove the CacheKey Dependency

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  • Ruby: "do this task eventually"

    - by marienbad
    I hope this question is clear enough -- if not let me know :) What API would I use when I want to write a procedure at runtime and then just run it eventually at low priority while continuing to do the important stuff right now? Example: link checker 1. I write a blog post with links represented by Link objects. I publish the post. 2. Eventually (at very low priority) the system gets around to fetching the URL of each Link object to make sure it's not broken and indicates that in a property of the Link object. 3. When a user visits my blog post, the render code that turns Link objects into HTML knows whether the links have been checked. I'm assuming there's a very general purpose API for doing this kind of "eventually/low priority" stuff.

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  • Memory leak while using emoticons on CRichEditCtrl

    - by Jorg B Jorge
    I'm developing a text editor class (for a chat application) based on CRichEditCtrl (MFC) with emoticon support. After i load the emoticon's bitmap, I use the function OleCreateStaticFromData to insert it into CRichEditCtrl. After that i just delete the bitmap object allocated by myself. I can verify (using a GDIView utility) that all resources i allocate have been properly released. This works perfectly: the bitmap (emoticon) is drawn on the CRichEditCtrl window and is handled just like a character. My problem is that I don't know how to deallocate the memory (internal) allocated by OleCreateStaticFromData to manage the bitmap (emoticon). The memory allocated for any emoticon used is never released, even if i delete the CRichEditCtrl object. I'd like to know how to fix that issue. Is that a MFC's issue or i'm doing something wrong ? Thx.

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  • Unset/Change Binding in WPF

    - by captcalamares
    How can I unset the binding applied to an object so that I can apply another binding to it from a different location? Suppose I have two data templates binded to the same object reference. Data Template #1 is the default template to be loaded. I try to bind a button command to a Function1 from my DataContext class: <Button Content="Button 1" CommandParameter="{Binding }" Command="{Binding DataContext.Function1, RelativeSource={RelativeSource AncestorType={x:Type Window}}}"/> This actually works and the function gets binded. However, when I try to load Data Template # 2 to the same object (while trying to bind another button command to a different function (Function2) from my DataContext class): <Button Content="Button 2" CommandParameter="{Binding }" Command="{Binding DataContext.Function2, RelativeSource={RelativeSource AncestorType={x:Type Window}}}" /> It doesn't work and the first binding is still the one executed. Is there a workaround to this? EDIT (for better problem context): I defined my templates in my Window.Resources: <Window.Resources> <DataTemplate DataType="{x:Type local:ViewModel1}"> <local:View1 /> </DataTemplate> <DataTemplate DataType="{x:Type local:ViewModel2}"> <local:View2 /> </DataTemplate> </Window.Resources> The View1.xaml and the View2.xaml contain the button definitions that I described above (I want them to command the control of my process flow). ViewModel1 and ViewModel2 are my ViewModels that implement the interface IPageViewModel which is the type of my variable CurrentPageViewModel. In my XAML, I binded ContentControl to the variable CurrentPageViewModel: <ContentControl Content="{Binding CurrentPageViewModel}" HorizontalAlignment="Center"/> In my .CS, I have a list defined as List<IPageViewModel> PageViewModels, which I use to contain the instances of my two View Models: PageViewModels.Add(new ViewModel1()); PageViewModels.Add(new ViewModel2()); // Set starting page CurrentPageViewModel = PageViewModels[0]; When I try to change my CurrentPageViewModel to the other view model, this is when I want the new binding to work. Unfortunately, it doesn't. Am I doing things the right way?

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  • What is the relationship between IRimTable and PersistenceStore?

    - by Martin
    The BlackBerry Desktop API has the interface IRimTable which apparently maps an "application database" on a BlackBerry device to a virtual structure (i.e, IRimTable has IRimRecords, each of which has IRimField) that developer can browse the handheld device data when it is connected to a desktop computer. Meanwhile, applications in the handheld device can store its data in PersistenceStore databases. The point where I'm stuck is the PersistenceStore API doesn't define any Table or Records or Fields. Does anybody knows what is the relationship between these two classes? And how does the mapping work (if at all) ?

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  • How can I dynamically override a classes "each" method?

    - by rewbs
    Groovy adds each() and a number of other methods to java.lang.Object. I can't figure out how to use the Groovy metaclass to dynamically replace the default each() on a Java class. I can see how to add new methods: MyJavaClass.metaClass.myNewMethod = { closure -> /* custom logic */ } new MyJavaClass().myNewMethod { item -> println item } // runs custom logic But it seems the same approach doesn't work when overriding methods: MyJavaClass.metaClass.each = { closure -> /* custom logic */ } new MyJavaClass().each { item -> println item } // runs Object.each() What am I doing wrong? How can I dynamically override each() in Groovy?

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  • Web2py controllers with parameters?

    - by nickfranceschina
    I am building an app using Web2py framework... I don't want to have to use the request object to get all of the querystring parameters, instead I'd like to build my controller with named parameters and have the router unpack the querystring (or form data) dictionary into the named parameters and call my controller. so instead of a controller method of create_user(): where I would use the global request() object and look through the vars list... I would prefer instead to have create_user(first_name, last_name, email): like I see in other MVC platforms. is this possible in Web2py already? or is there a plugin for it? or do I need to add that myself?

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  • SQL - Two foreign keys that have a dependency between them

    - by Brian
    The current structure is as follows: Table RowType: RowTypeID Table RowSubType: RowSubTypeID FK_RowTypeID Table ColumnDef: FK_RowTypeID FK_RowSubTypeID (nullable) In short, I'm mapping column definitions to rows. In some cases, those rows have subtype(s), which will have column definitions specific to them. Alternatively, I could hang those column definitions that are specific to subtypes off their own table, or I could combine the data in RowType and RowSubType into one table and work with a single ID, but I'm not sure either is a better solution (if anything, I'd lean towards the latter, as we mostly end up pulling ColumnDefs for a given RowType/RowSubType). Is the current design SQL Blasphemy? If I keep the current structuree, how do I maintain that if RowSubTypeID is specified in ColumnDef, that it must correspond to the RowType specified by RowTypeID? Should I try to enforce this with a trigger or am I missing a simple redesign that would solve the problem?

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  • Mixing table per subclass and per hierarchy in hibernate

    - by Xelluloid
    In my database there are two three tables. The first one, table ABSTRACT, holds three columns id, type, someText This table contains all abstract information for the abstract class abstract. Now the two tables CONCRETEONE and CONCRETETWO contain all information for the concrete classes concreteOne and concreteTwo. Now I know I could use the table per subclass strategy from hibernate to create a mapping with inheritance. But as I have a column that marks the type of the concrete implementation could it be possible to create some mixed behaviour like a table per subclass strategy with an discriminator?

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  • Can i Automap a tree heirarchy with fluent nhibernate?

    - by NakChak
    Is it possible to auto map a simple nested object structure? Something like this public class Employee : Entity { public Employee() { this.Manages = new List<Employee>(); } public virtual string FirstName { get; set; } public virtual string LastName { get; set; } public virtual bool IsLineManager { get; set; } public virtual Employee Manager { get; set; } public virtual IList<Employee> Manages { get; set; } } Causes the following error at run time: Repeated column in mapping for collection: SharpKtulu.Core.Employee.Manages column: EmployeeFk Is it possible to automap this sort of structure, or do i have over ride the auto mapper for this sort of structure?

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