Georg Kösters

GIS-application development with GEOOOA

We stress the need of a domain-tailored requirements engineering method for the development of GIS-applications. To this end, we discuss three GIS-application scenarios we have frequently encountered in real life projects. Our investigation reveals that conventional RE-methods like Coad/Yourdons Object-Oriented Analysis (OOA) are not capable of modelling GIS-specific requirements appropriately. To overcome the deficiencies of conventional OOA we introduce GEOOOA which extends OOA by domain-tailored primitives and allows for a more adequate treatment of GIS-specific requirements. We provide GEOOOA-models of three application scenarios which serve as first validation steps for the usefulness of the approach. Finally, we propose some methodological advices for a proper application of GEOOOA and sketch the GEOOOA-tool environment.

Coupling Use Cases and Class Models as a Means for Validation and Verification of Requirements Specifications

In many applications, especially from the business domain, the requirements specification mainly deals with use cases and class models. Unfortunately, these models are based on different modelling techniques and aim at different levels of abstraction, such that serious consistency and completeness problems are induced. To overcome these deficiencies, we refine activity graphs to meet the needs for a suitable modelling element for use case behaviour. The refinement in particular supports the proper coupling of use cases via activity graphs and the class model. The granularity and semantics of our approach allow for a seamless, traceable transition of use cases to the class model and for the verification of the class model against the use case model. The validation of the use case model and parts of the class model is supported as well. Experience from several applications has shown that the investment in specification, validation and verification not only pays off during system and acceptance testing but also significantly improves the quality of the final product.

Combined analysis of user interface and domain requirements

A requirements analysis method called FLUID is proposed which in contrast to conventional methods explicitly captures the requirements of direct manipulation user interfaces. The main concepts addressing the user interface requirements comprise a task model and a UIA model. The latter reveals the essential structure of the user interface and defines the basic dialog behavior, the presentation of domain model components on the screen, and links to the domain model. User interface requirements are described on a level of abstraction similar to that of conventional requirements, e.g. details of screen layout and dialog behavior are deferred to later development stages. The result of the entire requirements analysis-a combination of domain model and UIA model-serves as a basis for the further development process. The method also provides for (semi) automatic generation of user interface prototypes at intermediate stages of the analysis.

GeoOOA: object-oriented analysis for geographic information systems

We stress the need for a domain-tailored requirements engineering method in the development of GIS applications. To this end, we discuss three GIS application scenarios, the so-called topological scenario, the network scenario, and the (spatio-) temporal scenario, frequently encountered in real life projects. Our investigations reveal that conventional RE-methods like, for example, Coad/Yourdons Object-Oriented Analysis (OOA) cannot model GIS-specific requirements appropriately. To overcome the deficiencies of conventional OOA we introduce GeoOOA which complements OOA by suitable domain-tailored primitives and allows for a more adequate treatment of GIS-specific requirements. We provide GeoOOA models of a broadcasting corporation, an electric power supply system and a land registry as first validation steps for the usefulness of GeoOOA.

The GeoOOA-tool and its interface to open software development environments for GIS

GEoOOA is an object-oriented requirements engineering method with suitable geo-primitives which allows an adequate treatment of GIS-specific requirements. Since the applicability and success of any software engineering method depends heavily on an appropriate tool support, we propose the GEOOOA-tool, a CASE-tool supporting the development of GEOOOA-models. In this paper, we report on the editors, browsers, validators, and documentation aids of the GEoOOA-tool and sketch its connection to common open software development environments for GIS as well as some prototyping issues. Major parts of the tool have already been implemented and are available via anonymous ftp.

Ein Vorgehensmodell zur integrierten Anforderungsanalyse von Benutzungsschnittstelle und Anwendung

Wir stellen in diesem Artikel ein Vorgehensmodell fur die fruhen Phasen der Softwareentwicklung vor, das in besonderer Weise die Entwicklung direkt-manipulativer graphischer Benutzungsschnittstellen einbezieht. Anforderungen an Anwendung und Benutzungsschnittstelle werden aufeinander abgestimmt und parallel entwickelt. Zentrales Beschreibungsmittel fur Anforderungen an die Benutzungsschnittstelle sind abstrakte Sichten, die realisierungsunabhangig formuliert werden. Aus der vollstandigen Anforderungsanalyse kann die Softwarearchitektur von Benutzungsschnittstelle und Anwendung systematisch entwickelt werden.