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  • How do I refactor these two C# functions to abstrtact their logic from the specific class properties

    - by ObligatoryMoniker
    I have two functions whose underlying logic is the same but in one case it sets one property value on a class and in another case it sets a different one. How can I rewrite the following two functions to abstract away as much of the algorithm as possible so that I can make changes in logic in a single place? SetBillingAddress private void SetBillingAddress(OrderAddress newBillingAddress) { BasketHelper basketHelper = new BasketHelper(SiteConstants.BasketName); OrderAddress oldBillingAddress = basketHelper.Basket.Addresses[basketHelper.BillingAddressID]; bool NewBillingAddressIsNotOldBillingAddress = ((oldBillingAddress == null) || (newBillingAddress.OrderAddressId != oldBillingAddress.OrderAddressId)); bool BillingAddressHasBeenPreviouslySet = (oldBillingAddress != null); bool BillingAddressIsNotSameAsShippingAddress = (basketHelper.ShippingAddressID != basketHelper.BillingAddressID); bool NewBillingAddressIsNotShippingAddress = (newBillingAddress.OrderAddressId != basketHelper.ShippingAddressID); if (NewBillingAddressIsNotOldBillingAddress && BillingAddressHasBeenPreviouslySet && BillingAddressIsNotSameAsShippingAddress) { basketHelper.Basket.Addresses.Remove(oldBillingAddress); } if (NewBillingAddressIsNotOldBillingAddress && NewBillingAddressIsNotShippingAddress) { basketHelper.Basket.Addresses.Add(newBillingAddress); } basketHelper.BillingAddressID = newBillingAddress.OrderAddressId; basketHelper.Basket.Save(); } And here is the second one: SetShippingAddress private void SetBillingAddress(OrderAddress newShippingAddress) { BasketHelper basketHelper = new BasketHelper(SiteConstants.BasketName); OrderAddress oldShippingAddress = basketHelper.Basket.Addresses[basketHelper.ShippingAddressID]; bool NewShippingAddressIsNotOldShippingAddress = ((oldShippingAddress == null) || (newShippingAddress.OrderAddressId != oldShippingAddress.OrderAddressId)); bool ShippingAddressHasBeenPreviouslySet = (oldShippingAddress != null); bool ShippingAddressIsNotSameAsBillingAddress = (basketHelper.ShippingAddressID != basketHelper.BillingAddressID); bool NewShippingAddressIsNotBillingAddress = (newShippingAddress.OrderAddressId != basketHelper.BillingAddressID); if (NewShippingAddressIsNotOldShippingAddress && ShippingAddressHasBeenPreviouslySet && ShippingAddressIsNotSameAsBillingAddress) { basketHelper.Basket.Addresses.Remove(oldShippingAddress); } if (NewShippingAddressIsNotOldShippingAddress && NewShippingAddressIsNotBillingAddress) { basketHelper.Basket.Addresses.Add(newShippingAddress); } basketHelper.ShippingAddressID = newShippingAddress.OrderAddressId; basketHelper.Basket.Save(); } My initial thought was that if I could pass a class's property by refernce then I could rewrite the previous functions into something like private void SetPurchaseOrderAddress(OrderAddress newAddress, ref String CurrentChangingAddressIDProperty) and then call this function and pass in either basketHelper.BillingAddressID or basketHelper.ShippingAddressID as CurrentChangingAddressIDProperty but since I can't pass C# properties by reference I am not sure what to do with this code to be able to reuse the logic in both places. Thanks for any insight you can give me.

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  • How can I import one Gradle script into another?

    - by Ant
    Hi all, I have a complex gradle script that wraps up a load of functionality around building and deploying a number of netbeans projects to a number of environments. The script works very well, but in essence it is all configured through half a dozen maps holding project and environment information. I want to abstract the tasks away into another file, so that I can simply define my maps in a simple build file, and import the tasks from the other file. In this way, I can use the same core tasks for a number of projects and configure those projects with a simple set of maps. Can anyone tell me how I can import one gradle file into another, in a similar manner to Ant's task? I've trawled Gradle's docs to no avail so far. Additional Info After Tom's response below, I thought I'd try and clarify exactly what I mean. Basically I have a gradle script which runs a number of subprojects. However, the subprojects are all Netbeans projects, and come with their own ant build scripts, so I have tasks in gradle to call each of these. My problem is that I have some configuration at the top of the file, such as: projects = [ [name:"MySubproject1", shortname: "sub1", env:"mainEnv", cvs_module="mod1"], [name:"MySubproject2", shortname: "sub2", env:"altEnv", cvs_module="mod2"] ] I then generate tasks such as: projects.each({ task "checkout_$it.shortname" << { // Code to for example check module out from cvs using config from 'it'. } }) I have many of these sort of task generation snippets, and all of them are generic - they entirely depend on the config in the projects list. So what I want is a way to put this in a separate script and import it in the following sort of way: projects = [ [name:"MySubproject1", shortname: "sub1", env:"mainEnv", cvs_module="mod1"], [name:"MySubproject2", shortname: "sub2", env:"altEnv", cvs_module="mod2"] ] import("tasks.gradle") // This will import and run the script so that all tasks are generated for the projects given above. So in this example, tasks.gradle will have all the generic task generation code in, and will get run for the projects defined in the main build.gradle file. In this way, tasks.gradle is a file that can be used by all large projects that consist of a number of sub-projects with Netbeans ant build files.

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  • Paperclip: delete attachment and "can't convert nil into String" error

    - by snitko
    I'm using Paperclip and here's what I do in the model to delete attachments: def before_save self.avatar = nil if @delete_avatar == 1.to_s end Works fine unless @delete_avatar flag is set when the user is actually uploading the image (so the model receives both params[:user][:avatar] and params[:user][:delete_avatar]. This results in the following error: TypeError: can't convert nil into String from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:40:in `dirname' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:40:in `flush_writes' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:38:in `each' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:38:in `flush_writes' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/attachment.rb:144:in `save' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/attachment.rb:162:in `destroy' from /Work/project/src/app/models/user.rb:72:in `before_save' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/callbacks.rb:347:in `send' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/callbacks.rb:347:in `callback' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/callbacks.rb:249:in `create_or_update' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2538:in `save_without_validation' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/validations.rb:1078:in `save_without_dirty' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/dirty.rb:79:in `save_without_transactions' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:229:in `send' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:229:in `with_transaction_returning_status' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/connection_adapters/abstract/database_statements.rb:136:in `transaction' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:182:in `transaction' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:228:in `with_transaction_returning_status' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:196:in `save' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:208:in `rollback_active_record_state!' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:196:in `save' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:723:in `create' I assume it has something to do with the avatar.dirty? value because when it certainly is true when this happens. The question is, how do I totally reset the thing if there are changes to be saved and abort avatar upload when the flag is set?

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  • Why can't I use __getattr__ with Django models?

    - by Joshmaker
    I've seen examples online of people using __getattr__ with Django models, but whenever I try I get errors. (Django 1.2.3) I don't have any problems when I am using __getattr__ on normal objects. For example: class Post(object): def __getattr__(self, name): return 42 Works just fine... >>> from blog.models import Post >>> p = Post() >>> p.random 42 Now when I try it with a Django model: from django.db import models class Post(models.Model): def __getattr__(self, name): return 42 And test it on on the interpreter: >>> from blog.models import Post >>> p = Post() ERROR: An unexpected error occurred while tokenizing input The following traceback may be corrupted or invalid The error message is: ('EOF in multi-line statement', (6, 0)) --------------------------------------------------------------------------- TypeError Traceback (most recent call last) /Users/josh/project/ in () /Users/josh/project/lib/python2.6/site-packages/django/db/models/base.pyc in init(self, *args, **kwargs) 338 if kwargs: 339 raise TypeError("'%s' is an invalid keyword argument for this function" % kwargs.keys()[0]) -- 340 signals.post_init.send(sender=self.class, instance=self) 341 342 def repr(self): /Users/josh/project/lib/python2.6/site-packages/django/dispatch/dispatcher.pyc in send(self, sender, **named) 160 161 for receiver in self._live_receivers(_make_id(sender)): -- 162 response = receiver(signal=self, sender=sender, **named) 163 responses.append((receiver, response)) 164 return responses /Users/josh/project/python2.6/site-packages/photologue/models.pyc in add_methods(sender, instance, signal, *args, **kwargs) 728 """ 729 if hasattr(instance, 'add_accessor_methods'): -- 730 instance.add_accessor_methods() 731 732 # connect the add_accessor_methods function to the post_init signal TypeError: 'int' object is not callable Can someone explain what is going on? EDIT: I may have been too abstract in the examples, here is some code that is closer to what I actually would use on the website: class Post(models.Model): title = models.CharField(max_length=255) slug = models.SlugField() date_published = models.DateTimeField() content = RichTextField('Content', blank=True, null=True) # Etc... Class CuratedPost(models.Model): post = models.ForeignKey('Post') position = models.PositiveSmallIntegerField() def __getattr__(self, name): ''' If the user tries to access a property of the CuratedPost, return the property of the Post instead... ''' return self.post.name # Etc... While I could create a property for each attribute of the Post class, that would lead to a lot of code duplication. Further more, that would mean anytime I add or edit a attribute of the Post class I would have to remember to make the same change to the CuratedPost class, which seems like a recipe for code rot.

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  • Coming Up with a Good Algorithm for a Simple Idea

    - by mkoryak
    I need to come up with an algorithm that does the following: Lets say you have an array of positive numbers (e.g. [1,3,7,0,0,9]) and you know beforehand their sum is 20. You want to abstract some average amount from each number such that the new sum would be less by 7. To do so, you must follow these rules: you can only subtract integers the resulting array must not have any negative values you can not make any changes to the indices of the buckets. The more uniformly the subtraction is distributed over the array the better. Here is my attempt at an algorithm in JavaScript + underscore (which will probably make it n^2): function distributeSubtraction(array, goal){ var sum = _.reduce(arr, function(x, y) { return x + y; }, 0); if(goal < sum){ while(goal < sum && goal > 0){ var less = ~~(goal / _.filter(arr, _.identity).length); //length of array without 0s arr = _.map(arr, function(val){ if(less > 0){ return (less < val) ? val - less : val; //not ideal, im skipping some! } else { if(goal > 0){ //again not ideal. giving preference to start of array if(val > 0) { goal--; return val - 1; } } else { return val; } } }); if(goal > 0){ var newSum = _.reduce(arr, function(x, y) { return x + y; }, 0); goal -= sum - newSum; sum = newSum; } else { return arr; } } } else if(goal == sum) { return _.map(arr, function(){ return 0; }); } else { return arr; } } var goal = 7; var arr = [1,3,7,0,0,9]; var newArray = distributeSubtraction(arr, goal); //returned: [0, 1, 5, 0, 0, 7]; Well, that works but there must be a better way! I imagine the run time of this thing will be terrible with bigger arrays and bigger numbers. edit: I want to clarify that this question is purely academic. Think of it like an interview question where you whiteboard something and the interviewer asks you how your algorithm would behave on a different type of a dataset.

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  • Partial overriding in Java (or dynamic overriding while overloading)

    - by Lie Ryan
    If I have a parent-child that defines some method .foo() like this: class Parent { public void foo(Parent arg) { System.out.println("foo in Function"); } } class Child extends Parent { public void foo(Child arg) { System.out.println("foo in ChildFunction"); } } When I called them like this: Child f = new Child(); Parent g = f; f.foo(new Parent()); f.foo(new Child()); g.foo(new Parent()); g.foo(new Child()); the output is: foo in Parent foo in Child foo in Parent foo in Parent But, I want this output: foo in Parent foo in Child foo in Parent foo in Child I have a Child class that extends Parent class. In the Child class, I want to "partially override" the Parent's foo(), that is, if the argument arg's type is Child then Child's foo() is called instead of Parent's foo(). That works Ok when I called f.foo(...) as a Child; but if I refer to it from its Parent alias like in g.foo(...) then the Parent's foo(..) get called irrespective of the type of arg. As I understand it, what I'm expecting doesn't happen because method overloading in Java is early binding (i.e. resolved statically at compile time) while method overriding is late binding (i.e. resolved dynamically at compile time) and since I defined a function with a technically different argument type, I'm technically overloading the Parent's class definition with a distinct definition, not overriding it. But what I want to do is conceptually "partially overriding" when .foo()'s argument is a subclass of the parent's foo()'s argument. I know I can define a bucket override foo(Parent arg) in Child that checks whether arg's actual type is Parent or Child and pass it properly, but if I have twenty Child, that would be lots of duplication of type-unsafe code. In my actual code, Parent is an abstract class named "Function" that simply throws NotImplementedException(). The children includes "Polynomial", "Logarithmic", etc and .foo() includes things like Child.add(Child), Child.intersectionsWith(Child), etc. Not all combination of Child.foo(OtherChild) are solvable and in fact not even all Child.foo(Child) is solvable. So I'm best left with defining everything undefined (i.e. throwing NotImplementedException) then defines only those that can be defined. So the question is: Is there any way to override only part the parent's foo()? Or is there a better way to do what I want to do?

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  • Paperclip: delete attachments and "can't convert nil into String" error

    - by snitko
    I'm using Paperclip and here's what I do in the model to delete attachments: def before_save self.avatar = nil if @delete_avatar == 1.to_s end Works fine unless @delete_avatar flag is set when the user is actually uploading the image (so the model receives both params[:user][:avatar] and params[:user][:delete_avatar]. This results in the following error: TypeError: can't convert nil into String from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:40:in `dirname' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:40:in `flush_writes' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:38:in `each' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/storage.rb:38:in `flush_writes' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/attachment.rb:144:in `save' from /Work/project/src/vendor/plugins/paperclip/lib/paperclip/attachment.rb:162:in `destroy' from /Work/project/src/app/models/user.rb:72:in `before_save' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/callbacks.rb:347:in `send' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/callbacks.rb:347:in `callback' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/callbacks.rb:249:in `create_or_update' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:2538:in `save_without_validation' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/validations.rb:1078:in `save_without_dirty' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/dirty.rb:79:in `save_without_transactions' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:229:in `send' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:229:in `with_transaction_returning_status' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/connection_adapters/abstract/database_statements.rb:136:in `transaction' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:182:in `transaction' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:228:in `with_transaction_returning_status' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:196:in `save' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:208:in `rollback_active_record_state!' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/transactions.rb:196:in `save' from /usr/lib/ruby/gems/1.8/gems/activerecord-2.3.5/lib/active_record/base.rb:723:in `create' I assume it has something to do with the avatar.dirty? value because when it certainly is true when this happens. The question is, how do I totally reset the thing if there are changes to be saved and abort avatar upload when the flag is set?

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  • Observer pattern used with decorator pattern

    - by icelated
    I want to make a program that does an order entry system for beverages. ( i will probably do description, cost) I want to use the Decorator pattern and the observer pattern. I made a UML drawing and saved it as a pic for easy viewing. This site wont let me upload as a word doc so i have to upload a pic - i hope its easily viewable.... I need to know if i am doing the UML / design patterns correctly before moving on to the coding part. Beverage is my abstract component class. Espresso, houseblend, darkroast are my concrete subject classes.. I also have a condiment decorator class milk,mocha,soy,whip. would be my observer? because they would be interested in data changes to cost? Now, would the espresso,houseblend etc, be my SUBJECT and the condiments be my observer? My theory is that Cost is a changes and that the condiments need to know the changes? So, subject = esspresso,houseblend,darkroast,etc.. // they hold cost() Observer = milk,mocha,soy,whip? // they hold cost() would be the concrete components and the milk,mocha,soy,whip? would be the decorator! So, following good software engineering practices "design to an interface and not implementation" or "identify things that change from those that dont" would i need a costbehavior interface? If you look at the UML you will see where i am going with this and see if i am implementing observer + Decorator pattern correctly? I think the decorator is correct. since, the pic is not very viewable i will detail the classes here: Beverage class(register observer, remove observer, notify observer, description) these classes are the concrete beverage classes espresso, houseblend,darkroast, decaf(cost,getdescription,setcost,costchanged) interface observer class(update) // cost? interface costbehavior class(cost) // since this changes? condiment decorator class( getdescription) concrete classes that are linked to the 2 interface s and decorator are: milk,mocha,soy,whip(cost,getdescription,update) these are my decorator/ wrapper classes. Thank you.. Is there a way to make this picture bigger?

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  • How hard programming is? Really. [closed]

    - by Bubba88
    Hi! The question is about your perception of programming activity. How hard/exacting this task is? There is much buzz about programming nowadays, people say that programmers are smart, very technical and abstract at a time, know much about world, psychology etc.. They say, that programmers got really powerful brain thing, cause there is much to keep in consideration simultaneously again with much information folded into each other associatively (up 10 levels of folding they say))) Still, there are some terms to specify at our own.. So that is the question: What do you think about programming in general? Is it hard? Is it 'for everyone' or for the particular kind of people only? How much non-CS background do you need to program (just to program, really; enterprise applications for example)? How long is the learning curve? (again, for programming in general) And another bunch of random questions: - If you were not to like/love programming, would that be a serious trouble bothering your current employment? - If you were to start from the beginning, would you chose that direction this time? - What other areas (jobs or maybe hobbies) are comparable to programming in the way they can explode someone's lovely brain? - Is 'non turing-complete programming' (SQL, XML, etc.) comparable to what we do or is it really way easier, less requiring, cheap and akin to cooking :)? Well, the essence is: How would you describe programming activity WRT to its difficulty? Or, on the other hand: Did you ever catch yourself thinking at some point: OMG, it's sooo hard! I don't know how would I ever program, even carried away this way and doing programming just for fun? It's very interesting to know your opinion, your'e the programmers after all. I mean much people must be exaggerating/speculating about the thing they do not really know about. But that musn't be the case here on SO :) P.S.: I'll try my best to update this post later, and you please edit it too. At least I'll get decent English in my question text :)

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  • How to best integrate generated code

    - by Arne
    I am evaluating the use of code generation for my flight simulation project. More specifically there is a requirement to allow "the average engineer" (no offense I am one myself) to define the differential equations that describe the dynamic system in a more natural syntax than C++ provides. The idea is to devise a abstract descriptor language that can be easily understood and edited to generate C++ code from. This descriptor is supplied by the modeling engineer and used by the ones implementing and maintaining the simulation evironment to generate code. I've got something like this in mind: model Aircraft has state x1, x2; state x3; input double : u; input bool : flag1, flag2; algebraic double : x1x2; model Engine : tw1, tw2; model Gear : gear; model ISA : isa; trim routine HorizontalFight; trim routine OnGround, General; constant double : c1, c2; constant int : ci1; begin differential equations x1' = x1 + 2.*x2; x2' = x2 + x1x2; begin algebraic equations x1x2 = x1*x2 + x1'; end model It is important to retain the flexibility of the C language thus the descriptor language is meant to only define certain parts of the definition and implementation of the model class. This way one enigneer provides the model in from of the descriptor language as examplified above and the maintenance enigneer will add all the code to read parameters from files, start/stop/pause the execution of the simulation and how a concrete object gets instatiated. My first though is to either generate two files from the descriptor file: one .h file containing declarations and one .cpp file containing the implementation of certain functions. These then need to be #included at appropriate places [File Aircarft.h] class Aircraft { public: void Aircraft(..); // hand-written constructor void ReadParameters(string &file_name); // hand-written private: /* more hand wirtten boiler-plate code */ /* generate declarations follow */ #include "Aircraft.generated.decl" }; [File Aircraft.cpp] Aircarft::Aircraft(..) { /* hand-written constructer implementation */ } /* more hand-written implementation code */ /* generated implementation code follows */ #include "Aircraft.generated.impl" Any thoughts or suggestions?

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  • Silverlight with MVVM Inheritance: ModelView and View matching the Model

    - by moonground.de
    Hello Stackoverflowers! :) Today I have a special question on Silverlight (4 RC) MVVM and inheritance concepts and looking for a best practice solution... I think that i understand the basic idea and concepts behind MVVM. My Model doesn't know anything about the ViewModel as the ViewModel itself doesn't know about the View. The ViewModel knows the Model and the Views know the ViewModels. Imagine the following basic (example) scenario (I'm trying to keep anything short and simple): My Model contains a ProductBase class with a few basic properties, a SimpleProduct : ProductBase adding a few more Properties and ExtendedProduct : ProductBase adding another properties. According to this Model I have several ViewModels, most essential SimpleProductViewModel : ViewModelBase and ExtendedProductViewModel : ViewModelBase. Last but not least, according Views SimpleProductView and ExtendedProductView. In future, I might add many product types (and matching Views + VMs). 1. How do i know which ViewModel to create when receiving a Model collection? After calling my data provider method, it will finally end up having a List<ProductBase>. It containts, for example, one SimpleProduct and two ExtendedProducts. How can I transform the results to an ObservableCollection<ViewModelBase> having the proper ViewModel types (one SimpleProductViewModel and two ExtendedProductViewModels) in it? I might check for Model type and construct the ViewModel accordingly, i.e. foreach(ProductBase currentProductBase in resultList) if (currentProductBase is SimpleProduct) viewModels.Add( new SimpleProductViewModel((SimpleProduct)currentProductBase)); else if (currentProductBase is ExtendedProduct) viewModels.Add( new ExtendedProductViewModels((ExtendedProduct)currentProductBase)); ... } ...but I consider this very bad practice as this code doesn't follow the object oriented design. The other way round, providing abstract Factory methods would reduce the code to: foreach(ProductBase currentProductBase in resultList) viewModels.Add(currentProductBase.CreateViewModel()) and would be perfectly extensible but since the Model doesn't know the ViewModels, that's not possible. I might bring interfaces into game here, but I haven't seen such approach proven yet. 2. How do i know which View to display when selecting a ViewModel? This is pretty the same problem, but on a higher level. Ended up finally having the desired ObservableCollection<ViewModelBase> collection would require the main view to choose a matching View for the ViewModel. In WPF, there is a DataTemplate concept which can supply a View upon a defined DataType. Unfortunately, this doesn't work in Silverlight and the only replacement I've found was the ResourceSelector of the SLExtensions toolkit which is buggy and not satisfying. Beside that, all problems from Question 1 apply as well. Do you have some hints or even a solution for the problems I describe, which you hopefully can understand from my explanation? Thank you in advance! Thomas

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  • FormView templates break when refactored to Master/Content

    - by ZaijiaN
    Let's say I have an abstract class IA, with subclasses A1, A2, A3. For each subclass, I had a page with a FormView to insert/edit/view, with code specific to that class. The templates for insert/edit/view are all very similar, so it was mostly cut & paste, and the compiler had no problem that there were controls with the same IDs in the different templates. Something like this: <asp:FormView> <InsertItemTemplate> <asp:Label id="Label1" /> </InsertItemTemplate> <EditItemTemplate> <asp:Label id="Label1" /> </EdittItemTemplate> </asp:FormView> Much of the code/markup ended up being redundant across the pages, so I refactored it to use a master/content format, with the master page having content placeholders for the insert/edit/view templates. Master page: <asp:FormView> <InsertItemTemplate> <asp:ContentPlaceHolder ID="InsertItemTemplate"></asp:ContentPlaceHolder> </InsertItemTemplate> <EditItemTemplate> <asp:ContentPlaceHolder ID="EditItemTemplate"></asp:ContentPlaceHolder> </EdittItemTemplate> </asp:FormView> And content page: <asp:Content ContentPlaceHolderID="InsertItemTemplate"> <asp:Label id="Label1" /> </asp:Content> <asp:Content ContentPlaceHolderID="EditItemTemplate"> <asp:Label id="Label1" /> </asp:Content> In the content page templates, I'm doing the exact same thing I was doing before I refactored, but now the compiler is blowing up with the error BC30260: 'Label1' is already declared as 'Protected WithEvents Label1 As System.Web.UI.WebControls.Label' in this class. For some reason, it's not separating the controls in the content blocks the same way it did when they were in the templates, even though the content placeholders are in the individual templates. Is there a way around this, other than to rename all my controls?

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  • One-to-many relationship with JDO in Google App Engine

    - by Marvin
    I've followed the GAE docs on setting up one-to-many relationship in JDO but I'm still having trouble in retrieving the collection data back. I have no problem getting the other non-collection fields back. Here are my classes: @PersistenceCapable public class User{ @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) private Key key; @Persistent private String uniqueId; @Persistent private String email; @Persistent private List<Address> addresses = new ArrayList<Address>() ; ... } @PersistenceCapable public class Phone{ @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) private Key key; @Persistent private String number; ... } public class UserDaoImpl implements UserDao { public void insertUser(User user) { if(user.getKey() == null) { com.google.appengine.api.datastore.Key key = KeyFactory.createKey(User.class.getSimpleName(), user.getEmail()); user.setKey(key); } PersistenceManager pm = PersistenceManagerWrapper.getPersistenceManager(); notNull(user); try { pm.makePersistent(user); } finally { pm.close(); } } @SuppressWarnings("unchecked") public User getUser(String uniqueId) { PersistenceManager pm = PersistenceManagerWrapper.getPersistenceManager(); Query query = pm.newQuery(User.class); query.setFilter("uniqueId == uniqueIdParam"); query.declareParameters("String uniqueIdParam"); User user = null; try { List<User> users = (List<User>)(query.execute(uniqueId)); //TODO abstract this if(users.size() > 0) user = users.get(0); } finally { pm.close(); } return user; } } public class UserDaoImplTest { @Test public void getUserTest() { User user = createTestUser(); assertNotNull("The user object should not be null", user); userDao.insertUser(user); User returnedUser = userDao.getUser(TEST_USER_ID); assertNotNull("The returnedUser object should not be null", returnedUser); Assert.assertPropertyEqualsExcludeProperties("User Object", user, returnedUser, ""); } } When I run the test, all the properties for User is populated but the list of Phone if I get is empty.

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  • Middleware with generic communication media layer

    - by Tom
    Greetings all, I'm trying to implement middleware (driver) for an embedded device with generic communication media layer. Not sure what is the best way to do it so I'm seeking an advice from more experienced stackoverflow users:). Basically we've got devices around the country communicating with our servers (or a pda/laptop in used in field). Usual form of communication is over TCP/IP, but could be also using usb, RF dongle, IR, etc. The plan is to have object corresponding with each of these devices, handling the proprietary protocol on one side and requests/responses from other internal systems on the other. The thing is how create something generic in between the media and the handling objects. I had a play around with the TCP dispatcher using boost.asio but trying to create something generic seems like a nightmare :). Anybody tried to do something like that? What is the best way how to do it? Example: Device connects to our Linux server. New middleware instance is created (on the server) which announces itself to one of the running services (details are not important). The service is responsible for making sure that device's time is synchronized. So it asks the middleware what is the device's time, driver translates it to device language (protocol) and sends the message, device responses and driver again translates it for the service. This might seem as a bit overkill for such a simple request but imagine there are more complex requests which the driver must translate, also there are several versions of the device which use different protocol, etc. but would use the same time sync service. The goal is to abstract the devices through the drivers to be able to use the same service to communicate with them. Another example: we find out that the remote communications with the device are down. So we send somebody out with PDA, he connects to the device using USB cable. Starts up the application which has the same functionality as the timesync service. Again middleware instance is created (on the PDA) to translate communication between application and the device this time only using USB/serial media not TCP/IP as in previous example. I hope it makes more sense now :) Cheers, Tom

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  • Binding functions of derived class with luabind

    - by Anamon
    I am currently developing a plugin-based system in C++ which provides a Lua scripting interface, for which I chose to use luabind. I'm using Lua 5 and luabind 0.9, both statically linked and compiled with MSVC++ 8. I am now having trouble binding functions with luabind when they are defined in a derived class, but not its parent class. More specifically, I have an abstract base class called 'IPlugin' from which all plugin classes inherit. When the plugin manager initialises, it registers that class and its functions like this: luabind::open(L); luabind::module(L) [ luabind::class_("IPlugin") .def("start", (void(IPlugin::*)())&IPlugin::start) ]; As it is only known at runtime what effective plugin classes are available, I had to solve loading plugins in a kind of roundabout way. The plugin manager exposes a factory function to Lua, which takes the name of a plugin class and a desired object name. The factory then creates the object, registers the plugin's class as inheriting from the 'IPlugin' base class, and immediately calls a function on the created object that registers itself as a global with the Lua state, like this: void PluginExample::registerLuaObject(lua_State *L, string a_name) { luabind::globals(L)[a_name] = (PluginExample*)this; } I initially did this because I had problems with Lua determining the most derived class of the object, as if I register it from the StreamManager it is only known as a subtype of 'IPlugin' and not the specific subtype. I'm not sure anymore if this is even necessary though, but it works and the created object is subsequently accessible from Lua under 'a_name'. The problem I have, though, is that functions defined in the derived class, which were not declared at all in the parent class, cannot be used. Virtual functions defined in the base class, such as 'start' above, work fine, and calling them from Lua on the new object runs the respective redefined code from the 'PluginExample' class. But if I add a new function to 'PluginExample', here for example a function taking no arguments and returning void, and register it like this: luabind::module(L) [ luabind::class_("PluginExample") .def(luabind::constructor()) .def("func", &PluginExample::func) ]; calling 'func' on the new object yields the following Lua runtime error: No matching overload found, candidates: void func(PluginExample&) I am correctly using the ':' syntax so the 'self' argument is not needed and it seems suddenly Lua cannot determine the derived type of the object anymore. I am sure I am doing something wrong, probably having to do with the two-step binding required by my system architecture, but I can't figure out where. I'd much appreciate some help =)

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  • How to order a HasMany collection by a child property with Fluent NHibernate mapping

    - by Geoff Hardy
    I am using Fluent NHibernate to map the following classes: public abstract class DomainObject { public virtual int Id { get; protected internal set; } } public class Attribute { public virtual string Name { get; set; } } public class AttributeRule { public virtual Attribute Attribute { get; set; } public virtual Station Station { get; set; } public virtual RuleTypeId RuleTypeId { get; set; } } public class Station : DomainObject { public virtual IList<AttributeRule> AttributeRules { get; set; } public Station() { AttributeRules = new List<AttributeRule>(); } } My Fluent NHibernate mappings look like this: public class AttributeMap : ClassMap<Attribute> { public AttributeMap() { Id(o => o.Id); Map(o => o.Name); } } public class AttributeRuleMap : ClassMap<AttributeRule> { public AttributeRuleMap() { Id(o => o.Id); Map(o => o.RuleTypeId); References(o => o.Attribute).Fetch.Join(); References(o => o.Station); } } public class StationMap : ClassMap<Station> { public StationMap() { Id(o => o.Id); HasMany(o => o.AttributeRules).Inverse(); } } I would like to order the AttributeRules list on Station by the Attribute.Name property, but doing the following does not work: HasMany(o => o.AttributeRules).Inverse().OrderBy("Attribute.Name"); I have not found a way to do this yet in the mappings. I could create a IQuery or ICriteria to do this for me, but ideally I would just like to have the AttributeRules list sorted when I ask for it. Any advice on how to do this mapping?

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  • Error trying to run rails server

    - by David87
    I am trying to get a basic Rails application to run on my Mac OS X 10.6.5. I created a new app called demo (rails new demo), then went into the demo directory and tried to start the app with rails server. Here is the error message I received: "/Users/dpetrovi/.gem/ruby/1.8/gems/sqlite3-ruby-1.3.2/lib/sqlite3/sqlite3_native.bundle: [BUG] Segmentation fault ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10] Abort trap" I checked bundle install in the demo folder: "Using rake (0.8.7) Using abstract (1.0.0) Using activesupport (3.0.3) Using builder (2.1.2) Using i18n (0.5.0) Using activemodel (3.0.3) Using erubis (2.6.6) Using rack (1.2.1) Using rack-mount (0.6.13) Using rack-test (0.5.6) Using tzinfo (0.3.23) Using actionpack (3.0.3) Using mime-types (1.16) Using polyglot (0.3.1) Using treetop (1.4.9) Using mail (2.2.13) Using actionmailer (3.0.3) Using arel (2.0.6) Using activerecord (3.0.3) Using activeresource (3.0.3) Using bundler (1.0.7) Using thor (0.14.6) Using railties (3.0.3) Using rails (3.0.3) Using sqlite3-ruby (1.3.2) Your bundle is complete! Use bundle show [gemname] to see where a bundled gem is installed." Ruby, RubyGems, and sqlite3 were installed using MacPorts. Then I used gem to try to install the sqlite3-ruby interface. (sudo gem install sqlite3-ruby). Here is where I first noticed something could be off: "Successfully installed sqlite3-ruby-1.3.2 1 gem installed Installing ri documentation for sqlite3-ruby-1.3.2... No definition for libversion Enclosing class/module 'mSqlite3' for class Statement not known Installing RDoc documentation for sqlite3-ruby-1.3.2... No definition for libversion Enclosing class/module 'mSqlite3' for class Statement not known " I had rails running well on my system a few months ago, so I figured maybe I had some duplicates and it was trying to use the wrong one. I ran: "for cmd in ruby irb gem rake; do which $cmd; done" and got: "/opt/local/bin/ruby /opt/local/bin/irb /opt/local/bin/gem /opt/local/bin/rake" Checking where sqlite3 also gets me: "/opt/local/bin/sqlite3" so they all seem to be in the right place. Obviously /opt/local/bin is in my system path. If I check gems server, it shows that I have installed sqlite3-ruby 1.3.2 gem. Not sure what the problem could be? I am using ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10]. Macports claims this is the latest (although ive seen 1.9.1) One more thing-- in irb, I tried to check which version of sqlite3 my sqlite3-ruby is bound to, but I can only get this far: ":irb(main):001:0 require 'rubygems' = true irb(main):002:0 require 'sqlite3' /Users/dpetrovi/.gem/ruby/1.8/gems/sqlite3-ruby-1.3.2/lib/sqlite3/sqlite3_native.bundle: [BUG] Segmentation fault ruby 1.8.7 (2010-12-23 patchlevel 330) [i686-darwin10] Abort trap" Any suggestions? Im hoping I overlooked something obvious. Thanks

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  • Class hierarchy problem (with generic's variance!)

    - by devoured elysium
    The problem: class StatesChain : IState, IHasStateList { private TasksChain tasks = new TasksChain(); ... public IList<IState> States { get { return _taskChain.Tasks; } } IList<ITask> IHasTasksCollection.Tasks { get { return _taskChain.Tasks; } <-- ERROR! You can't do this in C#! I want to return an IList<ITask> from an IList<IStates>. } } Assuming the IList returned will be read-only, I know that what I'm trying to achieve is safe (or is it not?). Is there any way I can accomplish what I'm trying? I wouldn't want to try to implement myself the TasksChain algorithm (again!), as it would be error prone and would lead to code duplication. Maybe I could just define an abstract Chain and then implement both TasksChain and StatesChain from there? Or maybe implementing a Chain<T> class? How would you approach this situation? The Details: I have defined an ITask interface: public interface ITask { bool Run(); ITask FailureTask { get; } } and a IState interface that inherits from ITask: public interface IState : ITask { IState FailureState { get; } } I have also defined an IHasTasksList interface: interface IHasTasksList { List<Tasks> Tasks { get; } } and an IHasStatesList: interface IHasTasksList { List<Tasks> States { get; } } Now, I have defined a TasksChain, that is a class that has some code logic that will manipulate a chain of tasks (beware that TasksChain is itself a kind of ITask!): class TasksChain : ITask, IHasTasksList { IList<ITask> tasks = new List<ITask>(); ... public List<ITask> Tasks { get { return _tasks; } } ... } I am implementing a State the following way: public class State : IState { private readonly TaskChain _taskChain = new TaskChain(); public State(Precondition precondition, Execution execution) { _taskChain.Tasks.Add(precondition); _taskChain.Tasks.Add(execution); } public bool Run() { return _taskChain.Run(); } public IState FailureState { get { return (IState)_taskChain.Tasks[0].FailureTask; } } ITask ITask.FailureTask { get { return FailureState; } } } which, as you can see, makes use of explicit interface implementations to "hide" FailureTask and instead show FailureState property. The problem comes from the fact that I also want to define a StatesChain, that inherits both from IState and IHasStateList (and that also imples ITask and IHasTaskList, implemented as explicit interfaces) and I want it to also hide IHasTaskList's Tasks and only show IHasStateList's States. (What is contained in "The problem" section should really be after this, but I thought puting it first would be way more reader friendly). (pff..long text) Thanks!

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  • Non Document Centric SharePoint Workflow

    - by Dan Revell
    SharePoint workflows are document centric in that the base thing the workflow runs on has to be a thing; be it a document or just a list item. The workflow itself is task based, so stuff a user has to do. Now I can put any sort of code in these tasks that I want to and even put complex InfoPath forms in for the user to perform the task. This has been fine on all my previous workflows. But what if I want the tasks to be actual official forms themselves. The item that the workflow runs on is just some abstract concept like an event. An example could be an accident has happened. There isn't an accident form, but a whole set of forms that need to be completed by different people. Task forms aren't really a nice way to go, because it locks all the forms into the task list. You can only access the forms by not deleting the tasks when complete and going to the workflow summery and following the task links to the InfoPath forms or going straight to the tasks list and doing a filter on particular "accidents". These are official documents so ideally there would be a library for each type of document and the workflow would orchestrate the completion of the right forms. It would mean each task would have to create a new blank form and then link the user to that form. The user would go complete the form but then have to go back to the task form and click yes I've completed it until the workflow could progress. Well this is short of the workflow monitoring the forms library form for some completion trigger. But then it all gets messy with the user experience from clicking the link in the task email, to open the Infopath task form, to clicking the link in the subsequent Infopath library form and then return through these forms on completion. It just gets messy trying to retrofit this non document centric sort of workflow into SharePoint. I would really appreciate any input on what might be the best way to do this. Store the forms as task forms Store the forms as library forms and create/link from the task forms Store the forms as different infopath views, and use a forms library. The workflow would trigger variables that progress the view the infopath form shows. Using the same form template for both task forms and a forms library and when a task form is complete, copy the xml into the forms library to have a official record outside of the workflow. Thanks

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  • Constructor versus setter injection

    - by Chris
    Hi, I'm currently designing an API where I wish to allow configuration via a variety of methods. One method is via an XML configuration schema and another method is through an API that I wish to play nicely with Spring. My XML schema parsing code was previously hidden and therefore the only concern was for it to work but now I wish to build a public API and I'm quite concerned about best-practice. It seems that many favor javabean type PoJo's with default zero parameter constructors and then setter injection. The problem I am trying to tackle is that some setter methods implementations are dependent on other setter methods being called before them in sequence. I could write anal setters that will tolerate themselves being called in many orders but that will not solve the problem of a user forgetting to set the appropriate setter and therefore the bean being in an incomplete state. The only solution I can think of is to forget about the objects being 'beans' and enforce the required parameters via constructor injection. An example of this is in the default setting of the id of a component based on the id of the parent components. My Interface public interface IMyIdentityInterface { public String getId(); /* A null value should create a unique meaningful default */ public void setId(String id); public IMyIdentityInterface getParent(); public void setParent(IMyIdentityInterface parent); } Base Implementation of interface: public abstract class MyIdentityBaseClass implements IMyIdentityInterface { private String _id; private IMyIdentityInterface _parent; public MyIdentityBaseClass () {} @Override public String getId() { return _id; } /** * If the id is null, then use the id of the parent component * appended with a lower-cased simple name of the current impl * class along with a counter suffix to enforce uniqueness */ @Override public void setId(String id) { if (id == null) { IMyIdentityInterface parent = getParent(); if (parent == null) { // this may be the top level component or it may be that // the user called setId() before setParent(..) } else { _id = Helpers.makeIdFromParent(parent,getClass()); } } else { _id = id; } } @Override public IMyIdentityInterface getParent() { return _parent; } @Override public void setParent(IMyIdentityInterface parent) { _parent = parent; } } Every component in the framework will have a parent except for the top level component. Using the setter type of injection, then the setters will have different behavior based on the order of the calling of the setters. In this case, would you agree, that a constructor taking a reference to the parent is better and dropping the parent setter method from the interface entirely? Is it considered bad practice if I wish to be able to configure these components using an IoC container? Chris

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  • Create class instance in assembly from string name

    - by Arcadian
    I'm not sure if this is possible, and I'm quite new to using assemblies in C#.NET. What I would like to do is to create an instance of a class when supplied the string name of that class. Something like this: using MyAssembly; namespace MyNameSpace { Class MyClass { int MyValue1; int MyValue2; public MyClass(string myTypeName) { foreach(Type type in MyAssembly) { if((string)type == myTypeName) { //create a new instance of the type } } AssignInitialValues(//the type created above) } //Here I use an abstract type which the type above inherits from private void AssignInitialValues(AbstractType myClass) { this.value1 = myClass.value1; this.value2 = myClass.value2; } } } Obviously you cannot compare strings to types but it illustrates what I'm trying to do: create a type from a supplied string. Any thoughts? EDIT: After attempting: var myObject = (AbstractType) Activator.CreateInstance(null, myTypeName); AssignInitialValues(myObject); I get a number of errors: Inconsistent accessibility: parameter type 'MyAssembly.AbstractType' is less accessible than method 'MyNameSpace.MyClass.AssignInitialValues(MyAssembly.AstractType)' 'MyAssembly.AstractType' is inaccessible due to it's protection level The type or namespace name 'MyAssembly' could not be found (are you missing a using directive or an assembly reference?) The type or namespace name 'AbstractType' could not be found (are you missing a using directive or an assembly reference?) Not exactly sure why it can't find the assembly; I've added a reference to the assembly and I use a Using Directive for the namespace in the assembly. As for the protection level, it's calling classes (or rather the constructors of classes) which can only be public. Any clues on where the problem is? UPDATE: After looking through several articles on SO I came across this: http://stackoverflow.com/a/1632609/360627 Making the AbstractTypeclass public solved the issue of inconsistent accessibility. The new compiler error is this: Cannot convert type 'System.Runtime.Remoting.ObjectHandle' to 'MyAssembly.AbstractType' The line it references is this one: var myObject = (AbstractType) Activator.CreateInstance(null, myTypeName); Using .Unwrap() get's me past this error and I think it's the right way to do it (uncertain). However, when running the program I then get a TypeLoadException when this code is called. TypeLoadException: Could not load type ‘AbstractType’ from assembly ‘MyNameSpace'... Right away I can spot that the type its looking for is correct but the assembly it's looking in is wrong. Looking up the Activator.CreateInstance(String, String) method revealed that the null as the first argument means that the method will look in the executing assembly. This is contrary to the required behavior as in the original post. I've tried using MyAssembly as the first argument but this produces the error: 'MyAssembly' is a 'namespace' but is used like a 'variable' Any thoughts on how to fix this?

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  • Hide a base class method from derived class, but still visible outside of assembly

    - by clintp
    This is a question about tidyness. The project is already working, I'm satisfied with the design but I have a couple of loose ends that I'd like to tie up. My project has a plugin architecture. The main body of the program dispatches work to the plugins that each reside in their own AppDomain. The plugins are described with an interface, which is used by the main program (to get the signature for invoking DispatchTaskToPlugin) and by the plugins themselves as an API contract: namespace AppServer.Plugin.Common { public interface IAppServerPlugin { void Register(); void DispatchTaskToPlugin(Task t); // Other methods omitted } } In the main body of the program Register() is called so that the plugin can register its callback methods with the base class, and then later DispatchTaskToPlugin() is called to get the plugin running. The plugins themselves are in two parts. There's a base class that implements the framework for the plugin (setup, housekeeping, teardown, etc..). This is where DispatchTaskToPlugin is actually defined: namespace AppServer.Plugin { abstract public class BasePlugin : MarshalByRefObject, AppServer.Plugin.Common.IAppServerPlugin { public void DispatchTaskToPlugin(Task t) { // ... // Eventual call to actual plugin code // } // Other methods omitted } } The actual plugins themselves only need to implement a Register() method (to give the base class the delegates to call eventually) and then their business logic. namespace AppServer.Plugin { public class Plugin : BasePlugin { override public void Register() { // Calls a method in the base class to register itself. } // Various callback methods, business logic, etc... } } Now in the base class (BasePlugin) I've implemented all kinds of convenience methods, collected data, etc.. for the plugins to use. Everything's kosher except for that lingering method DispatchTaskToPlugin(). It's not supposed to be callable from the Plugin class implementations -- they have no use for it. It's only needed by the dispatcher in the main body of the program. How can I prevent the derived classes (Plugin) from seeing the method in the base class (BasePlugin/DispatchTaskToPlugin) but still have it visible from outside of the assembly? I can split hairs and have DispatchTaskToPlugin() throw an exception if it's called from the derived classes, but that's closing the barn door a little late. I'd like to keep it out of Intellisense or possibly have the compiler take care of this for me. Suggestions?

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  • C# - calling ext. DLL function containing Delphi "variant record" parameter

    - by CaldonCZE
    Hello, In external (Delphi-created) DLL I've got the following function that I need to call from C# application. function ReadMsg(handle: longword; var Msg: TRxMsg): longword; stdcall; external 'MyDll.dll' name 'ReadMsg'; The "TRxMsg" type is variant record, defined as follows: TRxMsg = record case TypeMsg: byte of 1: (accept, mask: longword); 2: (SN: string[6]); 3: (rx_rate, tx_rate: word); 4: (rx_status, tx_status, ctl0, ctl1, rflg: byte); end; In order to call the function from C#, I declared auxiliary structure "my9Bytes" containing array of bytes and defined that it should be marshalled as 9 bytes long array (which is exactly the size of the Delphi record). private struct my9Bytes { [MarshalAs(UnmanagedType.ByValArray, ArraySubType = UnmanagedType.U1, SizeConst = 9)] public byte[] data; } Then I declared the imported "ReadMsg" function, using the "my9bytes" struct. [DllImport("MyDll.dll")] private static extern uint ReadMsg(uint handle, ref my9Bytes myMsg); I can call the function with no problem... Then I need to create structure corresponding to the original "TRxMsg" variant record and convert my auxiliary "myMsg" array into this structure. I don't know any C# equivalent of Delphi variant array, so I used inheritance and created the following classes. public abstract class TRxMsg { public byte typeMsg; } public class TRxMsgAcceptMask:TRxMsg { public uint accept, mask; //... } public class TRxMsgSN:TRxMsg { public string SN; //... } public class TRxMsgMRate:TRxMsg { public ushort rx_rate, tx_rate; //... } public class TRxMsgStatus:TRxMsg { public byte rx_status, tx_status, ctl0, ctl1, rflg; //... } Finally I create the appropriate object and initialize it with values manually converted from "myMsg" array (I used BitConverter for this). This does work fine, this solution seems to me a little too complicated, and that it should be possible to do this somehow more directly, without the auxiliary "my9bytes" structures or the inheritance and manual converting of individual values. So I'd like to ask you for a suggestions for the best way to do this. Thanks a lot!

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  • How to access controller dynamic properties within a base controller's constructor in Grails?

    - by 4h34d
    Basically, I want to be able to assign objects created within filters to members in a base controller from which every controller extends. Any possible way to do that? Here's how I tried, but haven't got to make it work. What I'm trying to achieve is to have all my controllers extend a base controller. The base controller's constructor would be used to assign values to its members, those values being pulled from the session map. Example below. File grails-app/controllers/HomeController.groovy: class HomeController extends BaseController { def index = { render username } } File grails-app/controllers/BaseController.groovy: abstract class BaseController { public String username public BaseController() { username = session.username } } When running the app, the output shown is: 2010-06-15 18:17:16,671 [main] ERROR [localhost].[/webapp] - Exception sending context initialized event to listener instance of class org.codehaus.groovy.grails.web.context.GrailsContextLoaderListener org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'pluginManager' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is java.lang.RuntimeException: Unable to locate constructor with Class parameter for class org.codehaus.groovy.grails.commons.DefaultGrailsControllerClass ... Caused by: java.lang.RuntimeException: Unable to locate constructor with Class parameter for class org.codehaus.groovy.grails.commons.DefaultGrailsControllerClass ... Caused by: java.lang.reflect.InvocationTargetException ... Caused by: org.codehaus.groovy.grails.exceptions.NewInstanceCreationException: Could not create a new instance of class [com.my.package.controller.HomeController]! ... Caused by: groovy.lang.MissingPropertyException: No such property: session for class: com.my.package.controller.HomeController at com.my.package.controller.BaseController.<init>(BaseController.groovy:16) at com.my.package.controller.HomeController.<init>(HomeController.groovy) ... 2010-06-15 18:17:16,687 [main] ERROR core.StandardContext - Error listenerStart 2010-06-15 18:17:16,687 [main] ERROR core.StandardContext - Context [/webapp] startup failed due to previous errors And the app won't run. This is just an example as in my case I wouldn't want to assign a username to a string value, but rather a few objects pulled from the session map. The objects pulled from the session map are being set within filters. The alternative I see is being able to access the controller's instance within the filter's execution. Is that possible? Please help! Thanks a bunch!

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  • train wreck. Rails requires RubyGems >= 1.3.2

    - by JZ
    I recently upgraded ruby to ruby 1.8.7 (2009-06-12 patchlevel 174) [i686-darwin10] and I think I broke rails. When I attempt to load rails. I get an odd message. Please help! $ ruby script/server Rails requires RubyGems = 1.3.2. Please install RubyGems and try again: http://rubygems.rubyforge.org $ rails -v Rails 3.0.0.beta $ gem -v 1.3.6 $ which gem /usr/bin/gem $ whereis gem /usr/bin/gem $ which rails /usr/bin/rails $ whereis rails /usr/bin/rails $ /usr/bin/gem -v 1.3.6 $ /usr/bin/rails -v Rails 3.0.0.beta $ ruby script/console Rails requires RubyGems >= 1.3.2. Please install RubyGems and try again: http://rubygems.rubyforge.org $ gem list rails *** LOCAL GEMS *** rails (3.0.0.beta, 2.3.5, 2.2.2, 1.2.6) $ gem list *** LOCAL GEMS *** abstract (1.0.0) actionmailer (3.0.0.beta, 2.3.5, 2.2.2, 1.3.6) actionpack (3.0.0.beta, 2.3.5, 2.2.2, 1.13.6) actionwebservice (1.2.6) activemerchant (1.4.1) activemodel (3.0.0.beta) activerecord (3.0.0.beta, 2.3.5, 2.2.2, 1.15.6) activerecord-tableless (0.1.0) activeresource (3.0.0.beta, 2.3.5, 2.2.2) activesupport (3.0.0.beta, 2.3.5, 2.2.2, 1.4.4) acts_as_ferret (0.4.3) arel (0.2.pre) authlogic (2.1.3) builder (2.1.2) bundler (0.9.3) calendar_date_select (1.15) capistrano (2.5.2) cgi_multipart_eof_fix (2.5.0) chronic (0.2.3) columnize (0.3.1) compass (0.8.17) daemons (1.0.10) dnssd (0.6.0) erubis (2.6.5) fastercsv (1.5.0) fastthread (1.0.1) fcgi (0.8.7) ferret (0.11.6) flay (1.4.0) flog (2.4.0) gbarcode (0.98.16) gem_plugin (0.2.3) git (1.2.5) haml (2.2.15) haml-edge (2.3.100) highline (1.5.0) hoe (2.4.0) hpricot (0.6.164) i18n (0.3.3) javan-whenever (0.3.7) jeweler (1.4.0) jscruggs-metric_fu (1.1.5) json_pure (1.2.0) libxml-ruby (1.1.2) linecache (0.43) mail (2.1.2) mechanize (0.9.3) memcache-client (1.7.8) mime-types (1.16) mislav-will_paginate (2.3.11) mocha (0.9.7) mojombo-chronic (0.3.0) mongrel (1.1.5) needle (1.3.0) net-scp (1.0.1) net-sftp (2.0.1, 1.1.1) net-ssh (2.0.4, 1.1.4) net-ssh-gateway (1.0.0) nifty-generators (0.3.0) nokogiri (1.4.0) openrain-action_mailer_tls (1.1.3) passenger (2.2.5) polyglot (0.2.9) prawn (0.6.3) prawn-core (0.6.3) prawn-format (0.2.3) prawn-layout (0.3.2) prawn-security (0.1.1) rack (1.1.0, 1.0.1) rack-mount (0.4.5) rack-test (0.5.3) rails (3.0.0.beta, 2.3.5, 2.2.2, 1.2.6) railties (3.0.0.beta) rake (0.8.7, 0.8.3) rake-compiler (0.6.0) RedCloth (4.1.1) reek (1.2.6) relevance-rcov (0.9.2.1) rmagick (2.12.2) roodi (2.1.0) rsl-stringex (1.0.3) rspec (1.2.9) rspec-rails (1.2.9) ruby-debug (0.10.3) ruby-debug-base (0.10.3) ruby-openid (2.1.2) ruby-yadis (0.3.4) ruby2ruby (1.2.4) ruby_parser (2.0.4) rubyforge (2.0.3) rubygems-update (1.3.6, 1.3.5) rubynode (0.1.5) searchlogic (2.3.9) sexp_processor (3.0.3) spree (0.9.4) sqlite3-ruby (1.2.5, 1.2.4) termios (0.9.4) test-unit (2.0.5) text-format (1.0.0) text-hyphen (1.0.0) thor (0.13.0) tlsmail (0.0.1) topfunky-gruff (0.3.5) treetop (1.4.3) tzinfo (0.3.16) xmpp4r (0.4)

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