anyulled / laboratory-information-system

Laboratory information system

Solution proposal

High level refactoring strategy

In order to avoid touching the core to extend the core functionality, a Visitor interface should be implemented and it associated method. Thus, any class implementing the before-mentioned interface to add functionality and maintain a loose coupling between them. Later on, any new functionality to the core can be extended by creating new classes implementing the visitor pattern. A whole set of behaviors could be added by creating a single class, making it easy to maintain.

Proposed project structure

An ordinary java app structure is used.

• Model/domain classes are located at model package
• A service package contains an interface and its possible implementations.
• A legacy package contains legacy code to be extended, but not touched.

Design patterns used

• Visitor pattern: the visitor pattern is a behavioral design pattern by the Gang of Four with the intention of extending the current functionality without (barely) touching the code.
• Builder pattern: the builder pattern is a creational design pattern supporting the selective creation of complex objects in a simple way.
• Singleton pattern: one of the most famous design patterns, is used to maintain a single object throughout the app.

UML Diagram