Step 1.9 Grouping classes into modules

Grouping is the process of partitioning the model into related clusters of classes that can be viewed and understood in isolation. Grouping enhances understanding and management of large object models (refer chunking principle). When the model is partitioned in this way modules can be reused in new applications. They can also be replaced by newer modules as requirements evolve, enhancing the maintainability of the target system.

Rules for Identifying Modules

Classes in the same module:

• Require each other's events in the dynamic model
• Are created, read, updated or deleted by the same business process
• Are naturally clustered together in the object model and connected to the remainder of the model by few associations (optimally one).

Example of Partitioning into Modules