A cross-cutting concern (also known as a cross-cutting feature or cross-functional requirement) is a concern that affects multiple parts of a software system in a non-modular way. This means that it is not possible to isolate the concern to a single module or layer of the system, and it can therefore be difficult to manage and maintain.
Some common examples of cross-cutting concerns include:
- Security: Ensuring that the system is secure from unauthorized access, use, disclosure, disruption, modification, or destruction.
- Performance: Ensuring that the system is responsive, efficient, and scalable.
- Usability: Ensuring that the system is easy to learn, use, and understand.
- Internationalization: Enabling the system to be adapted to different languages and cultures.
- Localization: Adapting the system to a specific language and culture.
There are two main approaches to dealing with cross-cutting concerns:
- Aspect-oriented programming (AOP) is a software development paradigm that explicitly addresses cross-cutting concerns by modularizing them into separate modules called aspects. These aspects can then be woven into the code of the application at compile time or runtime.
- Traditional programming techniques can also be used to address cross-cutting concerns, but this can be more difficult and less maintainable. For example, a developer might need to duplicate code that is related to a cross-cutting concern in multiple places in the codebase.
The choice of which approach to use depends on the specific needs of the project. AOP is a good choice for projects with a large number of cross-cutting concerns, or for projects that need to be able to change the way that the system deals with these concerns easily. Traditional programming techniques are a good choice for projects with a small number of cross-cutting concerns, or for projects that do not need to be able to change the way that the system deals with these concerns easily.
