Research On The Refactoring Method Of An Embedded Electronic Chart System

With the change of the requirement and environment, it is possible that the functions of the software were changed or enhanced in the process of developing and maintaining. The design of the software isn't what it was, and the codes become difficult to understand and maintain with time elapsing. This is also a problem which arises in the developing process of the Embedded Electronic Chart System(ECS for short). Refactoring is the technique that can resolve this problem.This paper refactors ECS with this technique to improve the intelligibility and maintainability of the system. The important tasks of the paper include:The ECS characteristics are analyzed and the effects that the characteristics have on the refactoring are given. Then, a refactoring plan is planned includeing: the detecting of the "bad smells" in code and refactoring methods.The meaning of the "bad smells" in code is defined, and then the "bad smells" in code of the ECS are detected using the RuleChecker function and the Audit function of the testing tool Logiscope except human detecting. After detecting, the "bad smells" in code of the ECS are sorted.The refactoring methods for every "bad smells" in the ECS are given. The concepts of the simple refactoring and the complex refactoring are put forward, and then they are sorted in details according to the refactoring objects. Formalisms are used to preserve the behavior in the simple refactoring. The testing technique is used in the complex refactoring. A kind of test case generation technique for GUI software function testing is put forward. The results of refactoring indicate that the refactoring plan can improve the intelligibility and maintainability of the ECS.