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  • Proxy object references in MVC code

    - by krystan honour
    Hi there, I am just figuring out best practice with MVC now I have a project where we have chosen to use it in anger. My question is. If creating a list view which is bound to an IEnumerable is this bad practise? Would it be better to seperate the code generated by the WCF Service reference into a datastructure which essentially holds the same data but abstracts further from the service, meaning that the UI is totally unaware of the service implementation beneath. or do people just bind to the proxy object types and have done with it ? My personal feeling is to create an abstraction but this seems to violate the DRY principle.

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  • Delete only reference to child object

    - by Al
    I'm running in to a bit of a problem where any attempt to delete just the reference to a child also deletes the child record. My schema looks like this Person Organisation OrganisationContacts : Person OrgId PersonId Role When removing an Organisation i want to only delete the record in OrgnaisationContacts, but not touch the Person record. My Mapping looks like this Code: public OrganisationMap() { Table("Organsations"); .... HasMany<OrganisationContact>(x => x.Contacts) .Table("OrganisationContacts ") .KeyColumn("OrgId") .Not.Inverse() .Cascade.AllDeleteOrphan(); } public class OrganisationContactMap : SubclassMap<OrganisationContact> { public OrganisationContactMap() { Table("OrganisationContacts"); Map(x => x.Role, "PersonRole"); Map(x => x.IsPrimary); } } At the moment just removing a contact from the IList either doesn't reflect in the database at all, or it issues two delete statements DELETE FROM OrganisationContact & DELETE FROM Person, or tries to set PersonId to null in the OrganisationContacts table. All of which are not desirable. Any help would be great appreciated.

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  • Do ORMs normally allow circular relations? If so, how would they handle it?

    - by SeanJA
    I was hacking around trying to make a basic orm that has support for the one => one and one => many relationships. I think I succeeded somewhat, but I am curious about how to handle circular relationships. Say you had something like this: user::hasOne('car'); car::hasMany('wheels'); car::property('type'); wheel::hasOne('car'); You could then do this (theoretically): $u = new user(); echo $u->car->wheels[0]->car->wheels[1]->car->wheels[2]->car->wheels[3]->type; #=> "monster truck" Now, I am not sure why you would want to do this. It seems like it wastes a whole pile of memory and time just to get to something that could have been done in a much shorter way. In my small ORM, I now have 4 copies of the wheel class, and 4 copies of the car class in memory, which causes a problem if I update one of them and save it back to the database, the rest get out of date, and could overwrite the changes that were already made. How do other ORMs handle circular references? Do they even allow it? Do they go back up the tree and create a pointer to one of the parents? DO they let the coder shoot themselves in the foot if they are silly enough to go around in circles?

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  • Objective C Object Functioning & Passing Arrays

    - by Patrick
    I apologise if this has been asked before but I can't find the info I need. Basically I want a UITableView to be populated using info from a server, similar to the SeismicXML example. I have the parser as a separate object, is it correct to alloc, init an instance of that parser & then tell RootViewController to make it's table data source a copy of the parser's array. I can't include code because I haven't written anything yet, I'm just trying to get the design right before I start. Perhaps something like: xmlParser = [[XMLParser alloc] init]; [xmlParser getXMLData]; // Assuming xmlParser stores results in an array called returnedArray self.tableDataSource = xmlParser.returnedArray Is this the best way of doing it?

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  • Using DAO's or static methods in Domain Object with nHibernate

    - by mickyjtwin
    I am using nHibernate for the first time, and after alot of reading/researching, plus looking at other projects done with nHibernate, have seen a couple of implementation practices. I am looking for opinions about which would be best to use and why. Essentially the two methods are as follows: Using Data Access Objects and a DAO Factory. Example usage: INotificationListDAO nListDAO = NHDaoFactory.GetNotificationListDAO(); NotificationList list = nListDAO.GetByListID(""); Use Static methods in the Domain Object. Example usage: NotificationList list = NotificationList.GetByListID(""); NHHelper.Session.Get(id); NHHelper.Session basically calls the NHibernateSessionManager.Instace.GetSessionFrom(""). While both look similar, it is more to do with best practice. From what I understand, the first option is more so if you are developing enterprise level applications, where my requirements are more for mid-range websites.

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  • Strange Error - "Object moved to here."

    - by Dkong
    I get the strange error "Object moved to here." on a blank white page when I try to login on a site I created. It works fine locally but not when I deploy it to the test or production server. I am not doing anything odd, just using basic authentication code in a helper function as follows... public static bool AuthenticateUser(string Username, string Password, bool PersistLogin, string RedirectionURL) { if (Membership.ValidateUser(Username, Password)) { FormsAuthentication.SetAuthCookie(Username, PersistLogin); HttpContext.Current.Response.Redirect(RedirectionURL,true); return true; } else return false; }

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  • Core Data Predicate To Many

    - by Vikings
    I have a core data model that has a one to many relationship, there is a category, and it can contain many subcategories. Category <---- Subcategory I am trying to perform a fetch that checks if a particular Category contains a Subcategory with a particular name. Let's say I have two categories below, I want to fetch to see if there are any subcategories name "Apple" in the Category named "Fruits". Vetegables - Carrot - Lettuce Fruits - Apple - Orange - Pear Code: - (SubCategory *)searchForSubCategoryWithName:(NSString *)subCategory inCategory:(Category *)category { NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"SubCategory" inManagedObjectContext:self.beer.managedObjectContext]; [fetchRequest setEntity:entity]; NSPredicate *predicate = [NSPredicate predicateWithFormat:@"name == [c] %@", subCategory]; [fetchRequest setPredicate:predicate]; NSError *error; NSArray *fetchedObjects = [self.beer.managedObjectContext executeFetchRequest:fetchRequest error:&error]; if (fetchedObjects != nil && fetchedObjects.count > 0) { return [fetchedObjects objectAtIndex:0]; } else { return nil; } }

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  • Printing the address of a struct object

    - by bdhar
    I have a struct like this typedef struct _somestruct { int a; int b; }SOMESTRUCT,*LPSOMESTRUCT; I am creating an object for the struct and trying to print it's address like this int main() { LPSOMESTRUCT val = (LPSOMESTRUCT)malloc(sizeof(SOMESTRUCT)); printf("0%x\n", val); return 0; } ..and I get this warning warning C4313: 'printf' : '%x' in format string conflicts with argument 1 of type 'LPSOMESTRUCT' So, I tried to cast the address to int like this printf("0%x\n", static_cast<int>(val)); But I get this error: error C2440: 'static_cast' : cannot convert from 'LPSOMESTRUCT' to 'int' What am I missing here? How to avoid this warning? Thanks.

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  • Opening IProject properties when another (adaptable to IProject) object is selected

    - by Stan
    I have a custom view displaying a hierarchy model of the current project. The root element is of class MyProject which is my own class, but it represents one Eclipse IProject, and it's adaptable to IProject. I have a "properties" menu option in the popup menu for that view, and I'd like to open up IProject's properties when a MyProject object is selected. PropertyDialogAction only looks for property pages registered for MyProject and doesn't give me a chance to offer an adapter -- or, at least, I don't know how to offer one. What's the proper solution for this? In the meantime, I've overridden PropertyDialogAction to handle my class in the special way I require, but that seems like quite a kludge to get this done.

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  • Synchronizing access to an inner object's methods?

    - by user291701
    Suppose I have the following: public class Foo { private ReadingList mReadingList = new ReadingList(); public ReadingList getReadingList() { synchronized (mReadingList) { return mReadingList; } } } If I try modifying the ReadingList object in two threads, the synchronization above won't help me, right?: // Thread 1 foo1.getReadingList().setName("aaa"); // Thread 2 foo2.getReadingList().setName("bbb"); do I have to wrap each method I want synchronized like so: public class Foo { private ReadingList mReadingList = new ReadingList(); public synchronized void setReadingListName(String name) { mReadingList.setName(name); } public synchronized void setReadingListAuthor(String author) { mReadingList.setAuthor(author); } ... and so on for each method of ReadingList I want exposed and synched? I'd end up just writing wrapper methods for each method of ReadingList. Thanks

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  • C++ inheritance and member function pointers

    - by smh
    In C++, can member function pointers be used to point to derived (or even base) class members? EDIT: Perhaps an example will help. Suppose we have a hierarchy of three classes X, Y, Z in order of inheritance. Y therefore has a base class X and a derived class Z. Now we can define a member function pointer p for class Y. This is written as: void (Y::*p)(); (For simplicity, I'll assume we're only interested in functions with the signature void f() ) This pointer p can now be used to point to member functions of class Y. This question (two questions, really) is then: Can p be used to point to a function in the derived class Z? Can p be used to point to a function in the base class X?

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  • How can I define an empty array in a Perl construtor?

    - by Laimoncijus
    I am just beginner with Perl, so if it sounds stupid - sorry for that :) My problem is - I am trying to write a class, which has an empty array, defined in constructor of a class. So I am doing this like this: package MyClass; use strict; sub new { my ($C) = @_; my $self = { items => () }; bless $self, ref $C || $C; } sub get { return $_[0]->{items}; } 1; Later I am testing my class with simple script: use strict; use Data::Dumper; use MyClass; my $o = MyClass->new(); my @items = $o->get(); print "length = ", scalar(@items), "\n", Dumper(@items); And while running the script I get following: $ perl my_test.pl length = 1 $VAR1 = undef; Why am I doing wrong what causes that I get my items array filled with undef? Maybe someone could show me example how the class would need to be defined so I would not get any default values in my array?

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  • failure on creating a Scikits.TimeSeries object

    - by user311906
    Hi All I am trying to create a scikit.timeseries object starting from 2 datetime objects. If I understood correctly it should be possible to create a scikits.timeseries starting from datetime objects. I try the following code but it says that Insufficient parameters. The 2 datetime differs for few microseconds. In this case what should be the value for freq parameter? Is what I am trying allowed? In theory, since timeseries can be based on datetime objects it should be possible to hanlde up to microsecond , is this correct? I think that this is not really clear to me. Regards Eo import datetime import sckilits.timeseries as ts tm1 = datetime.datetime( 2010,1,1, 10,10,2, 123456 ) tm2 = datetime.datetime( 2010,1,1, 10,10,2, 345678 ) d = [ tm1, tm2 ] tseries = ts.time_series( dates=d ) tseries = ts.time_series( d )

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  • Events in Classes (VB.NET)

    - by Otaku
    I find that I write a lot of code within my classes to keep properties in sync with each other. I've read about Events in Classes, but have not been able to wrap my head around how to make them work for what I'm looking for. I could use some advice here. For example, in this one I always want to keep myColor up to date with any change whatsoever in any or all of the Red, Green or Blue properties. Class myColors Private Property Red As Byte Private Property Green As Byte Private Property Blue As Byte Private Property myColor As Color Sub New() myColor = Color.FromArgb(0, 0, 0) End Sub Sub ChangeRed(ByVal r As Byte) Red = r myColor = Color.FromArgb(Red, Green, Blue) End Sub Sub ChangeBlue(ByVal b As Byte) Blue = b myColor = Color.FromArgb(Red, Green, Blue) End Sub End Class If one or more of those changes, I want myColor to be updated. Easy enough as above, but is there a way to work with events that would automatically do this so I don't have to put myColor = Color.FromArgb(Red, Green, Blue) in every sub routine?

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  • In Drools Rules, how to use two different ArrayList objects,obj1 is used in rule 1 and obj2 used in rule2?

    - by Jenn
    I am doing ksession.insert(list) and after that I have to fire rule 1 in the drl file, then ksession.insert(list) and fire rule 2 in the drl. Could someone tell me how to achieve this. I read about agenda filters and facthandles but do not really know how to get this to work Below is some code: ArrayList list = new ArrayList(); list.add(product1); list.add(product2); list.add(product3); ksession.insert(list); ksession.fireAllRules("fire rule 1 in drl"); //remove list? ArrayList list2 = new ArrayList(); list2.add(str1); list2.add(str2); list2.add(str3); ksession.insert(list2); ksession.fireAllRules("fire rule 2 in drl");

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  • How to use a servlet to repsond to a request for an object

    - by Rick
    I'm sure this is easy, but I don't work with website development very often and I'm lost on this one. I have a web application that needs to support multiple clients with different settings, icons and other content. The contents of these files are in separate directories for each client. What I would like to do is respond to a request sent to a jsp/java servlet. The servlet will look up the proper folder location in a database (I have the database stuff working) and send the actual object to the requesting page whether it is xml, graphic or video. How do I do that? What methods should I be using. Help I'm lost! :(

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  • Partial class or "chained inheritance"

    - by Charlie boy
    Hi From my understanding partial classes are a bit frowned upon by professional developers, but I've come over a bit of an issue; I have made an implementation of the RichTextBox control that uses user32.dll calls for faster editing of large texts. That results in quite a bit of code. Then I added spellchecking capabilities to the control, this was made in another class inheriting RichTextBox control as well. That also makes up a bit of code. These two functionalities are quite separate but I would like them to be merged so that I can drop one control on my form that has both fast editing capabilities and spellchecking built in. I feel that simply adding the code form one class to the other would result in a too large code file, especially since there are two very distinct areas of functionality, so I seem to need another approach. Now to my question; To merge these two classes should I make the spellchecking RichTextBox inherit from the fast edit one, that in turn inherits RichTextBox? Or should I make the two classes partials of a single class and thus making them more “equal” so to speak? This is more of a question of OO principles and exercise on my part than me trying to reinvent the wheel, I know there are plenty of good text editing controls out there. But this is just a hobby for me and I just want to know how this kind of solution would be managed by a professional. Thanks!

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  • Howto check if a object is connected to another in hibernate

    - by codevourer
    Imagine two domain object classes, A and B. A has a bidirectional one-to-many relationship to B. A is related to thousands of B. The relations must be unique, it's not possible to have a duplicate. To check if an instance of B is already connected to a given instance of A, we could perform an easy INNER JOIN but this will only ensure the already persisted relations. What about the current transient relations? class A { @OneToMany private List<B> listOfB; } If we access the listOfB and perform a check of contains() this will fetch all the connected instances of B lazy from the datasource. I only want to validate them by their primary-key. Is there an easy solution where I can do things like "Does this instance of A is connected with this instance of B?" Without loading all these data into memory and perform a based on collections?

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  • Modules vs. Classes and their influence on descendants of ActiveRecord::Base

    - by Chris
    Here's a Ruby OO head scratcher for ya, brought about by this Rails scenario: class Product < ActiveRecord::Base has_many(:prices) # define private helper methods end module PrintProduct attr_accessor(:isbn) # override methods in ActiveRecord::Base end class Book < Product include PrintProduct end Product is the base class of all products. Books are kept in the products table via STI. The PrintProduct module brings some common behavior and state to descendants of Product. Book is used inside fields_for blocks in views. This works for me, but I found some odd behavior: After form submission, inside my controller, if I call a method on a book that is defined in PrintProduct, and that method calls a helper method defined in Product, which in turn calls the prices method defined by has_many, I'll get an error complaining that Book#prices is not found. Why is that? Book is a direct descendant of Product! More interesting is the following.. As I developed this hierarchy PrintProduct started to become more of an abstract ActiveRecord::Base, so I thought it prudent to redefine everything as such: class Product < ActiveRecord::Base end class PrintProduct < Product end class Book < PrintProduct end All method definitions, etc. are the same. In this case, however, my web form won't load because the attributes defined by attr_accessor (which are "virtual attributes" referenced by the form but not persisted in the DB) aren't found. I'll get an error saying that there is no method Book#isbn. Why is that?? I can't see a reason why the attr_accessor attributes are not found inside my form's fields_for block when PrintProduct is a class, but they are found when PrintProduct is a Module. Any insight would be appreciated. I'm dying to know why these errors are occurring!

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  • Help needed with Linq To Sql Query

    - by fearofawhackplanet
    I have the concept of valid/ordered transitions. So for example, it's not possible to move to status In progress from status Complete. Current and Next in table StatusTransition are FK (StatusType.Id). The Linq generator has created the following relations: Child Property Name: StatusTransitions1 Parent Property Name: StatusType1 Participating Properties: StatusType.Id -> StatusTransition.Next Child Property Name: StatusTransitions Parent Property Name: StatusType Participating Properties: StatusType.Id -> StatusTransition.Current I'm normally ok with Linq but I'm having difficulty getting the list of valid Next StatusTypes from the Current status. public List<StatusType> GetValidStatusTransitions(int statusId) { // trying to write something like the following // (obviously not correct) return _statusRepository .Where(s => s.Id == statusId) .Next.StatusTypes; }

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  • Custom business object comparer

    - by gruber
    Hello, I need to implement mechanism that compares two business objects and return the list of differences (past value, new value, isDifferenceBetter). Because not all fields of class has to be compared and one fields need to be compared with different function then the other (sometimes < is better sometimes is better ... ) I figured out that I need to implelemnt custom attribute and give it to each field that has to be compared in this object. This attribute must have: - name - delegate or sth to point to the function which would be applied for comparision (dont know how to do it so far) So could anyone suggest me if its a good idea? Maybe any other ideas. Using attributes I would be able to use refflection to iterate through each field with attribute and invoke needed delegate. thanks for help bye

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  • Getting JSON object from php authentication objective c

    - by iError
    I am trying to authenticate using the below code NSString *urlAsString =[NSString stringWithFormat:@"http://www.myurl.com/abc/authenticate.php"]; NSURL *url = [NSURL URLWithString:urlAsString]; NSMutableURLRequest *urlRequest = [NSMutableURLRequest requestWithURL:url]; [urlRequest setTimeoutInterval:30.0f]; [urlRequest setHTTPMethod:@"POST"]; [urlRequest addValue:@"test" forHTTPHeaderField:@"m_username" ]; [urlRequest addValue:@"123" forHTTPHeaderField:@"m_password" ]; [[NSURLConnection alloc] initWithRequest:urlRequest delegate:self]; NSOperationQueue *queue = [[NSOperationQueue alloc] init]; [NSURLConnection sendAsynchronousRequest:urlRequest queue:queue completionHandler:^(NSURLResponse *response,NSData *data, NSError *error) { if ([data length] >0 && error == nil){ html = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; NSLog(@"HTML = %@", html); receivedData = [NSMutableData data]; } else if ([data length] == 0 && error == nil){ NSLog(@"Nothing was downloaded."); } else if (error != nil){ NSLog(@"Error happened = %@", error); } }]; // Start loading data NSURLConnection *theConnection = [[NSURLConnection alloc] initWithRequest:urlRequest delegate:self]; if (theConnection) { // Create the NSMutableData to hold the received data receivedData = [NSMutableData data]; } else { // Inform the user the connection failed. } My username password is correct, I think I am not making the proper call thats why I dont get the desired results and the web service is receiving the null parameters. What can be the issue? Any help appreciated.

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