Serializing Configurations for a Dependency Injection / Inversion of Control
- by Joshua Starner
I've been researching Dependency Injection and Inversion of Control practices lately in an effort to improve the architecture of our application framework and I can't seem to find a good answer to this question. It's very likely that I have my terminology confused, mixed up, or that I'm just naive to the concept right now, so any links or clarification would be appreciated.
Many examples of DI and IoC containers don't illustrate how the container will connect things together when you have a "library" of possible "plugins", or how to "serialize" a given configuration. (From what I've read about MEF, having multiple declarations of [Export] for the same type will not work if your object only requires 1 [Import]). Maybe that's a different pattern or I'm blinded by my current way of thinking.
Here's some code for an example reference:
public abstract class Engine {
}
public class FastEngine : Engine {
}
public class MediumEngine : Engine {
}
public class SlowEngine : Engine {
}
public class Car
{
public Car(Engine e)
{
engine = e;
}
private Engine engine;
}
This post talks about "Fine-grained context" where 2 instances of the same object need different implementations of the "Engine" class: http://stackoverflow.com/questions/2176833/ioc-resolve-vs-constructor-injection
Is there a good framework that helps you configure or serialize a configuration to achieve something like this without hard coding it or hand-rolling the code to do this?
public class Application
{
public void Go()
{
Car c1 = new Car(new FastEngine());
Car c2 = new Car(new SlowEngine());
}
}
Sample XML:
<XML>
<Cars>
<Car name="c1" engine="FastEngine" />
<Car name="c2" engine="SlowEngine" />
</Cars>
</XML>
