Autumn SALE
/ Refactoring / Techniques / Moving Features between Objects

Remove Middle Man

Problem

A class has too many methods that simply delegate to other objects.

Solution

Delete these methods and force the client to call the end methods directly.

Before
Remove Middle Man - Before
After
Remove Middle Man - After

Why Refactor

To describe this technique, we'll use the terms from Hide Delegate, which are:

  • Server is the object to which the client has direct access.

  • Delegate is the end object that contains the functionality needed by the client.

There are two types of problems:

  1. The server-class doesn't do anything itself and simply creates needless complexity. In this case, give thought to whether this class is needed at all.

  2. Every time a new feature is added to the delegate, you need to create a delegating method for it in the server-class. If a lot of changes are made, this will be rather tiresome.

How to Refactor

  1. Create a getter for accessing the delegate-class object from the server-class object.

  2. Replace calls to delegating methods in the server-class with direct calls for methods in the delegate-class.