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Object Oriented Programming

Query Objects instead of Repositories

The repository pattern is often used to encapsulate simple and sometimes rather complex query logic.   However, it has also been morphed into handling persistence and is often used as another layer of abstraction from your data mapping layer.   This blog post show you how to slim down and simplify your repositories or possibly eliminate them all together by using query objects. A typical repository will look something like this: public interface IProductRepository { void Insert(Product product); void Delete(Product product); IEnumerable<Product> GetById(Guid id); IEnumerable<Product> GetAllActive(); IEnumerable<Product> FindByName(string name); IEnumerable<Product> FindBySku(string name); IEnumerable<Product> Find(string keyword, int limit, int page); IEnumerable<Product> GetRelated(Guid id); } Each… Read More »Query Objects instead of Repositories

Throw Out Your Dependency Injection Container

Dependency injection containers (aka inversion of control containers) seem to be common in most modern applications.  There is no argument against the value dependency injection, but I do have a couple arguments against using a dependency injection container.  Like many other design patterns and practices, over time the development community seems to forget the original problem the pattern or practice was solving. Constructor & Setter Injection Passing your dependencies via the constructor is generally a better way of injecting dependencies instead of  setters. Constructor injection gives you a much clearer definition of what dependencies are needed in order to construct the object into a valid… Read More »Throw Out Your Dependency Injection Container

Greg Young: 8 Lines of Code

Greg Young gave a good talk titled 8 Lines of Code, discussing simplicity, dependencies, and magic. Magic is always something I try and identify and stay away from in my own code, however I really failed to realize how much magic goes on in some of the libraries/frameworks that I often use.  Entity Framework and nHibernate come to mind.  You really should understand the magic happening in these libraries to use them.  Which is very problematic. If you take the dependency ownership seriously, then a lot of folks developing the front-end of a “modern” web applications are in a world of… Read More »Greg Young: 8 Lines of Code