Hello, Just out of curiosity, for applications that have a fairly complicated module tree, would something like sqlite/sql compact edition work well for message passing? So if I have modules containing data such as: \SubsystemA\SubSubSysB\ModuleB\ModuleDataC, \SubSystemB\SubSubSystemC\ModuleA\ModuleDataX Using traditional message pas...
I've been reading a lot about python-way lately so my question is How to do dependency injection python-way? I am talking about usual scenarios when, for example, service A needs access to UserService for authorization checks. ...
Given that it's one of the hard things in computer science, does anyone know of a way to set up a plugable caching strategy? What I'm thinking of would allow me to write a program with minimal thought as to what needs to be cached (e.i. use some sort of boiler-plate, low/no cost pattern that compiles away to nothing anywhere I might wa...
My iPhone app relies on a vendor's XML feed to provide data. But that feed is not locked down. The vendor could change the format of the XML at any time, although so far they've promised not to. Since I might want to tell my app to use a different URL for its data source, I'd like to set up a single "Command Central" Web page, on my ow...
So, there is going to be one login form; however 1 of 3 types of members will be signing in member_type_a, member_type_b, member_type_c all of whom have some of the same properties, and some whom may have specific methods and/or properties to them. I want the class to be saved to a session variable for use with member area pages. Any s...
i have looked into design patterns and mvc and understand the basics of it. but i don't understand if these classes that these patterns are constituted of are library classes or model classes. i'm using codeigniter and don't know if i should put the classes in models folder or libraries folder. the classes could be: observers and ob...
Suppose I have a class A, and A1, A2 inherits from A. There are 2 functions: List<A1> getListA1(){...} List<A2> getListA2(){...} Now I want to do something similar to both A1 and A2 in another function public void process(List<A>){...} If I want to pass the instance of either ListA1 or ListA2, of course the types doesn't match beca...
My team would like to spend some time at lunch learning design patterns. Previously, we watched some videos on Javascript which we found very useful as a way to start discussions. We would like to do the same thing with design patterns so that we don't have to spend a lot of time (outside of work) researching individual patterns in ord...
In a legacy codebase I have a very large class with far too many fields/responsibilities. Imagine this is a Pizza object. It has highly granular fields like: hasPepperoni hasSausage hasBellPeppers I know that when these three fields are true, we have a Supreme pizza. However, this class is not open for extension or change, so I can'...
Assume I have a class a: class a { public: void load_data( ); private: void check_data( ); void work_data( ); void analyze_data( ); } Those functions all do something with the class or one of its members. However this function: bool validate_something( myType myData ) { if ( myData.blah > 0 && myData.blah < 100 ) ...
I understand that MVC & MVP are design patterns that are commonly used for web development, as well as ASP.NET WebForms (more of an anti-pattern, really!). What other patterns are used in web application development? I'm not necessarily saying I want to learn/use new patterns just to be different - I do believe there's a lot of value i...
Hi Folks, I want to get your opinion on this. I have a class which is derived from a base class. I don't have control over the code in the base class and it is critical to the system that I derive from it. In my class I inherite two methods that are critical to the system and are used in pretty much every function, many times. I inte...
I have an application which uses MyGeneration's dOODads ORM to generate it's Data Access Layer. dOODad works by generating a persistance class for each table in the database. It works like so: // Load and Save Employees emps = new Employees(); if(emps.LoadByPrimaryKey(42)) { emps.LastName = "Just Got Married"; emps.Sav...
I have a class that holds arbitrary state and it's defined like this: class AbstractFoo { }; template <class StatePolicy> class Foo : public StatePolicy, public AbstractFoo { }; The state policy contains only protected attributes that represent the state. The state might be the same for multiple behaviors and they can be replaced at ...
Hello ! I am building graphs. A graph consists of nodes linked each other with links (indeed my dear). In order to assign a given behavior to each node, I implemented the strategy pattern. class Node { public BaseNodeBehavior Behavior {get; set;} } As a result, in many parts of the application, I am extensively using type reflect...
Hi, Is there any keyword or design pattern for doing this? Please check the update public abstract class Root { public abstract void foo(); } public abstract class SubClass extends Root { public void foo() { // Do something //---------------- Update -------------------// // This method contains im...
I have a DownloadManager class that manages multiple DownloadItem objects. Each DownloadItem has events like ProgressChanged and DownloadCompleted. Usually you want to use the same event handler for all download items, so it's a bit annoying to have to set the event handlers over and over again for each DownloadItem. Thus, I need to dec...
whenever i use a open source library eg. Doctrine i always ending up coding a class (so called Facade) to use the Doctrine library. so next time i want to create a user i just type: $fields = array('name' => 'peter', 'email' => '[email protected]'); Doctrine_Facade::create_entity($entity, $fields); then it creates an entity with the ...
Does anybody know of any libraries that use design patterns that are implemented using compile-time techniques e.g. template metaprogramming? I know that Loki implements a few but I need to find other libraries. ...
Here's an example of the pattern I'm using in my javascript objects these days (this example relies on jQuery). http://pastie.org/private/ryn0m1gnjsxdos9onsyxg It works for me reasonably well, but I'm guessing there's something wrong, or at least sub-optimal about it, I'm just curious to get people's opinions. Here's a smaller, inline ...