38.4. Requirements for the Persistence Service and Framework
For the NextGen POS application, we need a persistence service to be built with a persistence framework (which could be used to also create other persistence services). Let's call the framework PFW (Persistence Framework). PFW is a simplified frameworka full-blown, industrial-strength persistence framework is outside the scope of this introduction.The framework should provide functions such as:
- store and retrieve objects in a persistent storage mechanism
- commit and rollback transactions
The design should be extendable to support different storage mechanisms and formats, such as RDBs, records in flat files, or XML in files.