Roswitha Bardohl

Attributed graph transformation with node type inheritance

The aim of this paper is to integrate typed attributed graph transformation with node type inheritance. Borrowing concepts from object oriented systems, the main idea is to enrich the attributed type graph with an inheritance relation and a set of abstract nodes. In this way, a node type inherits the attributes and edges of all its ancestors. Based on these concepts, it is possible to define abstract productions, containing abstract nodes. These productions are equivalent to a number of concrete productions, resulting from the substitution of the abstract node types by the node types in their inheritance clan. Therefore, productions become more compact and suitable for their use in combination with meta-modelling. The main results of this paper show that attributed graph transformation with node type inheritance is fully compatible with the existing concept of typed attributed graph transformation.

Integrating Meta-modelling Aspects with Graph Transformation for Efficient Visual Language Definition and Model Manipulation

Visual languages (VLs) play a central role in modelling various system aspects. Besides standard languages like UML, a variety of domain-specific languages exist which are the more used the more tool support is available for them. Different kinds of generators have been developed which produce visual modelling environments based on VL specifications. To define a VL, declarative as well as constructive approaches are used. The meta modelling approach is a declarative one where classes of symbols and relations are defined and associated to each other. Constraints describe additional language properties. Defining a VL by a graph grammar, the constructive way is followed where graphs describe the abstract syntax of models and graph rules formulate the language grammar.

A visual environment for visual languages

The visual environment GENGED supports the visual definition of visual languages (VLs). Each VL is defined by an alphabet and a grammar. From a specific VL-definition, a VL-specification is generated which is the input of a graphical editor allowing for syntax-directed editing of diagrams over the specified VL. GENGED as well as each VL is based on the well-defined concepts of algebraic graph transformation and graphical constraint solving. The underlying formalism is hidden from the user, but it is essential for a formal presentation and manipulation of graphical structures. In this contribution, the GENGED concepts and environment are briefly proposed and illustrated by the definition of a simple kind of the well-known statechart language.

Scenario animation for visual behavior models: A generic approach

Visualizing and simulating formal models in a flexible way becomes increasingly important for the design of complex systems. With GenGED, a tool is available which automatically generates a visual environment to process (create, edit, check, simulate) visual models over a specified visual language. Both the specification of the language and the model manipulation are based on graph grammars. In this paper, we present the means to transform visual models into application oriented views, called scenario views. We show how a model is consistently transferred to a scenario views and animated there. The extension of GenGED concerning scenario animation is discussed.

GenGED: A visual definition tool for visual modeling environments

In this paper, we give a brief overview on GenGED that allows for the visual definition and generation of visual modeling environments. Depending on the underlying visual modeling language, different components are suitable in a visual modeling environment. GenGED supports the definition and generation of editors, parsers, and simulators.

Visual Language Parsing in GenGEd1

Abstract G en GE d supports the visual specification of visual languages and the generation of syntax-directed editors. However, syntax-directed editing is not always desired by the user. Therefore we extended G en GE d by parsing facilities which allow for free editing as well.

Conceptual Model of the Graphical Editor GENGED for the Visual Definition of Visual Languages

This contribution presents a conceptual model of GenGEd, an editor supporting the visual definition of visual languages (VLs). A VL is defined by an alphabet and a grammar. These constituents are the input of a syntax-directed graphical editor allowing the manipulation of visual sentences over VL.

A formal framework for the development of concurrent object-based systems

In this paper we present a framework for developing concurrent object-based systems. The framework is based on graph grammars and includes techniques for specification, simulation, animation and verification.

Visual Design of Software Architecture and Evolution based on Graph Transformation

Abstract The paper suggests a two-level approach to describe visually software architectures and their evolution. One visual modeling formalism is used to describe the architecture level while another is used to model the behavior of each component (component specification level). Graph transformation is applied for both levels to describe the modeling formalisms and the model evolution in a formal way. The graph transformation based visual modeling approach GenGEd allows the designer to define the concrete and abstract syntax of each formalism. Thus, the choice of the visual formalisms is not restricted to existing ADLs or modeling languages but new visual languages can be defined by the user according to the problem domain. The architecture and component specifications are related over their abstract syntax. Here, it is possible to enforce coherence between the two levels while the user is changing the model in the editor generated by the GenGEd tool. The ideas are illustrated by a small example using UML-like class diagrams for the architecture and Petri net like networks for the component behavior.

GenGEd: A Development Environment for Visual Languages

Within this contribution GENGED is presented, a development environment for visual languages. GENGED offers a hybrid language for defining the syntax of visual languages consisting of an alphabet and a grammar. Correspondingly, the main components of GENGED are given by an alphabet and a grammar editor. The syntax description is the input of a diagram editor allowing the syntax-directed manipulation of diagrams. The grammar definition as well as the manipulation of diagrams is based on algebraic graph transformation and graphical constraint solving.