What is a common strategy to break existing cyclic dependencies?

What is a common strategy to break existing cyclic dependencies?

• A. Remove all dependencies by refactoring into a single module.
• B. Duplicate modules until no cycle.
• C. Introduce interfaces or an abstraction layer to invert dependencies.
• D. Convert cycles into parallel execution.

Answer: (C)

Breaking cyclic dependencies often comes from dependency inversion: have modules depend on an abstraction rather than on each other directly. By introducing interfaces or an abstraction layer that captures the behavior one module needs from the other, both sides interact through that common interface instead of concrete implementations. The concrete classes then live behind these abstractions and can be provided from outside, for example with dependency injection. This inversion of control removes the direct circular link and decouples the components, making the code easier to test and maintain. Other approaches don’t address the underlying coupling. Refactoring everything into a single module defeats modularity. Duplicating modules merely hides the cycle behind duplication and creates maintenance headaches. Trying to run the cycle in parallel doesn’t remove the dependency direction and can lead to correctness issues.

Breaking cyclic dependencies often comes from dependency inversion: have modules depend on an abstraction rather than on each other directly. By introducing interfaces or an abstraction layer that captures the behavior one module needs from the other, both sides interact through that common interface instead of concrete implementations. The concrete classes then live behind these abstractions and can be provided from outside, for example with dependency injection. This inversion of control removes the direct circular link and decouples the components, making the code easier to test and maintain.

Other approaches don’t address the underlying coupling. Refactoring everything into a single module defeats modularity. Duplicating modules merely hides the cycle behind duplication and creates maintenance headaches. Trying to run the cycle in parallel doesn’t remove the dependency direction and can lead to correctness issues.