␡
- Mysterious Name
- Duplicated Code
- Long Function
- Long Parameter List
- Global Data
- Mutable Data
- Divergent Change
- Shotgun Surgery
- Feature Envy
- Data Clumps
- Primitive Obsession
- Repeated Switches
- Loops
- Lazy Element
- Speculative Generality
- Temporary Field
- Message Chains
- Middle Man
- Insider Trading
- Large Class
- Alternative Classes with Different Interfaces
- Data Class
- Refused Bequest
- Comments
This chapter is from the book
This chapter is from the book
This chapter is from the book
This chapter is from the book
Alternative Classes with Different Interfaces
One of the great benefits of using classes is the support for substitution, allowing one class to swap in for another in times of need. But this only works if their interfaces are the same. Use Change Function Declaration (124) to make functions match up. Often, this doesn’t go far enough; keep using Move Function (198) to move behavior into classes until the protocols match. If this leads to duplication, you may be able to use Extract Superclass (375) to atone.