4.1. What’s aspect-oriented programming?

As stated earlier, aspects help to modularize cross-cutting concerns. In short, a cross-cutting concern can be described as any functionality that affects multiple points of an application. Security, for example, is a cross-cutting concern, in that many methods in an application can have security rules applied to them. Figure 4.1 gives a visual depiction of cross-cutting concerns.

Figure 4.1. Aspects modularize cross-cutting concerns, applying logic that spans multiple application objects.