Question

I want to have an abstract class Server with an abstract method called Initialize that passes a reference to IConnection, by reference. From there, a class deriving from this should be able to essentially specialize the IConnection object with its implementation of Initialize. This is fine except that I want to also have two abstract methods: DataSent and DataReceived and I want to use the specialized type in their signature, perhaps through generics.

Something like this is what I want:

public override void Initialize(ref IConnection connection)
{
    connection = new MySpecialConnection(connection);
}

public override void DataSent(MySpecialConnection connection, byte[] data)
{

}

public override void DataReceived(MySpecialConnection connection, byte[] data)
{

}

Is there an easy way to do this? I’ve been playing around with generics for the better portion of a few days and nobody I have spoken with online has been able to come up with a solution.

For those of you who think you see the solution: when I tried doing this with generics it was pretty complex and due to variance problems it was just not wanting to work right.

Answer 1

Why not just this?

abstract class Server<T> where T : IConnection
{
    public abstract void Initialize(ref IConnection conn);
    public abstract void DataSent(T conn, byte[] data);
    public abstract void DataReceived(T conn, byte[] data);
}

class SpecialServer : Server<SpecialConnection>
{
    public override void Initialize(ref IConnection conn)
    {
        conn = new SpecialConnection(conn);
    }

    public override void DataSent(SpecialConnection conn, byte[] data)
    {
        //things
    }

    public override void DataReceived(SpecialConnection conn, byte[] data)
    {
        //stuff
    }
}