On Class Diagrams, Crossings and Metrics

As a standardized software engineering diagram, the UML class diagram provides various information on the static structure of views on software while design, implementation and maintenance phase. This talk gives an overview on drawing UML class diagrams in hierarchical fashion. Therefore, common elements of class diagrams are introduced and aesthetic rules for drawing UML class diagrams are given. These rules are based on four disciplines involved in the reading process of diagrams. After a brief introduction to our drawing algorithm, an extensive extension of the well-known Sugiyama algorithm, two details are highlighted: A new crossing reduction algorithm is presented and compared to existing ones and issues on measuring the quality of a layout are discussed

Evolutionary Layout of Graph Transformation Sequences

Graph transformation is used in various different research areas and has been implemented in several tool environments. However, the layout of graph transformation sequences is often perceived as not optimal and remains to be a difficult task. This is partly due to the slightly different requirements for layouting graph transformation sequences compared to standard graph sequences. In this paper, we clearly define these special requirements and present a layout algorithm which fulfills them. This layout algorithm allows the user to keep track of changes during transformation steps by introducing a concept of node aging and protection of senior node positions in the layout. Furthermore, this layout algorithm introduces a concept of layout patterns. We extended the well-known spring embedder layout algorithm by these new concepts and implemented the new algorithm in AGG, an environment for Attributed Graph Grammars. The layout algorithm has been tested with various graph grammars. A brief outlook describes how this layout algorithm can also be used for different kinds of graph sequences, e.g. sequences of successively developing class diagrams

Experimental Object-Oriented Modelling

This thesis examines object-oriented modelling in experimental system development. Object-oriented modelling aims at representing concepts and phenomena of a problem domain in terms of classes and objects. Experimental system development seeks active experimentation in a system development project through, e.g., technical prototyping and active user involvement. We introduce and examine "experimental object-oriented modelling" as the intersection of these practices

A Generic Technique for Domain-Specific Visual Language Model Refactoring to Patterns

As the popularity of domain-specific visual languages (DSVLs) grows, concerns have arisen regarding quality assurance and evolvability of their meta-models and model instances. In this paper we address aspects of automated DSVL model instance modification for quality improvement based on refactoring specifications. We propose a graph transformation-based visual language approach for DSVL authors to specify the matching and discovery of DSVL “bad model smells” and the application of pattern-based solutions in a DSVL meta-tool. As an outcome, DSVL users are provided with pattern-based design evolution support as refactorings for their DSVL-based domain models

Domain-specific language design requires feature descriptions

A domain-specific language (DSL) provides a notation tailored towards an application domain and is based on the relevant concepts and features of that domain. As such, a DSL is a means to describe and generate members of a family of programs in the domain. A prerequisite for the design of a DSL is a detailed analysis and structuring of the application domain.Graphical feature diagrams have been proposed to organize the dependencies between such features, and to indicate which ones are common to all family members and which ones vary. In this paper, we study feature diagrams in more details, as well as their relationship to domain-specific languages. We propose the Feature Description Language (FDL), a textual language to describe features.We explore automated manipulation of feature descriptions such as normalization, expansion to disjunctive normal form, variability computation and constraint satisfaction. Feature descriptions can be directly mapped to UML diagrams which in their turn can be used for Java code generation. The value of FDL is assessed via a case study in the use and expressiveness of feature descriptions for the area of documentation generators

Reuse of use cases diagrams: an approach based on ontologies and semantic web technologies

Software reuse is defined as the use of any artifact, or part thereof, created before, on a new Project. This practice has significant benefits in reducing costs and increasing quality and productivity in software development. Numerous approaches have been proposed aimed mostly at the source code reuse, but this type of reuse has its limitations because development platforms and technologies are constantly changing. Then, it is necessary to apply reuse over software artifacts created at higher levels of software life cycle such as requirements specification. This paper presents a tool for the reuse of use case diagrams by storing their information in OWL ontology and the use of Semantic Web technologies.Software reuse is defined as the use of any artifact, or part thereof, created before, on a new Project. This practice has significant benefits in reducing costs and increasing quality and productivity in software development. Numerous approaches have been proposed aimed mostly at the source code reuse, but this type of reuse has its limitations because development platforms and technologies are constantly changing. Then, it is necessary to apply reuse over software artifacts created at higher levels of software life cycle such as requirements specification. This paper presents a tool for the reuse of use case diagrams by storing their information in OWL ontology and the use of Semantic Web technologies