Centralized Request Logic

Often in a web application, logic is duplicated among several types of requests. Three patterns are used to consolidate this logic into a central location:

• Front Controller
• Intercepting Filter
• Page Controller with common ancestor class

All three patterns interoperate well.

A Front Controller and Page Controller base classes are fairly interchangable and mostly used for implementing application specific logic. Intercepting filters are used more for de-coupled request processing logic.

The type of logic that benefits from centralization include:

• Logging and Auditing
• Debugging
• Security / Authorization
• HTTP Header Manipulation
• Response compression