UML Model Verification And Test Based On Graph Transformation

With the development of software engineering, UML modeling language is more and more important in software engineering, and UML has become a major standard in software requirements analysis and modeling. However, UML is a semi-formal language, so it is difficult to precisely define model without any errors. Views of UML model maybe have inconsistencies between each other and UML model itself also could conflicts with business rules of a specific domain. Although manually checking can solve the problem of inconsistency between each views of UML, it greatly costs time and effort with no good effect. When it comes to the problem of contradiction with the business rules, manual checking is powerless. Because it cannot find the problem of contradiction until system is practically running.In order to detect errors in UML model in early phase of software development, save cost and improve efficiency, this paper does some research on how to verify and test UML model. At first, this paper using the OCL expressions defines the rules of consistency of static UML model, then use some related tools to check whether each view of UML model conflicts with each other. On that basis, this paper comprehensively combines several common views of UML and OCL expressions, which represent the business rules, then generates medium aggregation model. This medium aggregation model includes more information than any single view and is easy to be tested. That solves the problem of fully testing the UML model from any single view. This paper then utilizes genetic algorithm to automatically make test cases, which save the tediousness of manually constructing test cases. After that, this paper tests the medium aggregation model with test cases, tracks the state of system or objects, and compares with OCL expressions. In this way, it can find the contradiction between UML model and business rules in detail, and achieve the goal of testing UML model.Medium aggregation model in this paper is a kind of direct graph, and has the similar structure with control flow graph in structural program design. Medium aggregation model makes the recessive information in original UML model become apparent. Tracking data and control flow with medium aggregation model is also inclined to easier. Utilizing the mature technology of structure program test can test the UML model better.