Sample Code Before class Car { void drive() { System.out.println("Driving a car"); } } class Truck extends Car { void load() { System.out.println("Loading cargo"); } void unload() { System.out.println("Unloading cargo"); } } // Truck reuses driving method // Overriding it would be another code smell // Violating Liskov Substitution rule After abstract class Vehicle { // 2. Create an abstract class // with shared behavior and no implementation abstract void drive(); // 1. Identify common behaviors in both classes // 3. Move common logic to the abstract class } class Car extends Vehicle { // 4. Update subclasses to inherit from the abstract class void drive() { System.out.println("Driving a car"); } } class Truck extends Vehicle { // 4. Update subclasses to inherit from the abstract class void drive() { System.out.println("Driving a truck"); // Implementation is different than the car's } void load() { System.out.println("Loading cargo"); } void unload() { System.out.println("Unloading cargo"); } } Type

[x] Semi-Automatic

Safety

This refactoring is safe if you identify all common behaviors correctly and move one method at a time running the tests.

Why is the Code Better?

It reduces duplication, simplifies maintenance, and makes it easier to extend functionality by adding new concrete realizations.

How Does it Improve the Bijection?

By introducing an abstract class, the code better reflects the real-world hierarchy, creating a clear relationship between the generic and specific types.

Refactor with AI

| Without Proper Instructions | With Specific Instructions | |----|----| | ChatGPT | ChatGPT | | Claude | Claude | | Perplexity | Perplexity | | Copilot | Copilot | | Gemini | Gemini | | Meta AI | Meta AI |