How should I model my code to maximize code re-use in this specific situation?

Question

Updated: See end of question for how I implemented the solution.

Sorry for the poorly-worded question, but I wasn\'t sure how best to ask it. I\'m not sure

Answer 1

Create an abstract base class and have the method that needs to be changed as abstract protected e.g.

public abstract class OutboxManager 
{
    private List<OutboxMsg> _OutboxMsgs;

    public void DistributeOutboxMessages()
{
    try {
        RetrieveMessages();
        SendMessagesToVendor();
        MarkMessagesAsProcessed();
    }
    catch (Exception ex) {
        LogErrorMessageInDb(ex);
    }
 }

    private void RetrieveMessages() 
    {
      //retrieve messages from the database; poplate _OutboxMsgs.
      //This code stays the same in each implementation.
    }

    protected abstract void SendMessagesToVendor();   // <== THIS CODE CHANGES EACH IMPLEMENTATION


    private void MarkMessagesAsProcessed()
    {
      //If SendMessageToVendor() worked, run this method to update this db.
      //This code stays the same in each implementation.
    }

    private void LogErrorMessageInDb(Exception ex)
    {
      //This code writes an error message to the database
      //This code stays the same in each implementation.
    }
}

Each implementation inherits from this abstract class but only provides the implementation for SendMessagesToVendor() the shared implementation is defined in the abstract base class.