Hierarchical object-oriented Petri net for scenario-based functional behaviors modeling

Abstract

The concept of scenario has been widely used in recent years as object-oriented paradigm has gained more popularity among practioners. Although the scenarios cannot be fully exploited due to the existence of many variants, major object-oriented development process adopt it for managing the entire software development activities. There are two major drawbacks in applying the scenario-based modeling technique. One is the difference of abstraction levels between scenarios. This causes from the facts that the requirements of complex systems are elicited from various sources such as users and documents. The other drawback is the difficulty in eliciting the whole requirements of the system at once such that the same problem occurs in requirements elicitation of a system in general. Specially, scenarios from the requirements of a large and complex system can be partially redundant or missed because of eliciting the requirements from users of various domains. Therefore, it is difficult to collect the full set of scenarios for a system at the initial phase of requirements engineering. This can cause the changes of scenarios such as appearing new scenarios and modifying scenarios partially during scenario modeling phase. This thesis proposes a high-level Petri net based on object-oriented concepts, called HOONet(Hierarchical Object-Oriented Petri Net) in order to solve the above mentioned drawbacks. We formally describe the definition of our HOONet and suggest the representation schemes of object-oriented concepts by the HOONet when modeling a system. Additionally, we explain the recipes for coordinating the different abstraction levels between scenarios and reflecting the requirements changes into scenario-based modeling. Coordination of the different abstraction levels, first, is solved by incorporating abstraction mechanism with a general high-level Petri net such as colored Petri nets. When a system is represented by its functional hierarchy, function units in high-l...