Manfred Nagl

Building tightly integrated software development environments: the IPSEN approach

Overview: Introduction, classification, and global approach.- The outside perspective: Tools, environments, their integration, and user interface.- Internal conceptual modeling: Graph grammar specifications.- Realization: Derivation of efficient tools.- Current and future work, open problems.- Conclusion: Summary, evaluation, and vision.

Building integrated software development environments. Part I: tool specification

The conceptual modeling approach of the IPSEN (Integrated Project Support Environment) project for building highly integrated environments is based on using attributed graphs to model and implement arbitrary object structures, in particular all kinds of software documents and their relationships. A language based on graph grammars, called PROGRESS (PROgrammed Graph REwriting SyStems), and a suitable method for the application of this language, called graph grammar engineering, have been developed over the last ten years. This language and method are being extensively used for specifying the complex graph structures of internal document representations as well as for specifying the functionality of all tools (editors, browsers, analyzers, debuggers) working on these internal rpresentations. This paper explains the language and the method for applying the language based on a pragmatic nontrivial example of a software production process and its corresponding documents. In particular, it is shown why and how a graph grammar-based strongly typed language is perfectly suitable to formally specify highly integrated software tools. In addition, it is shown that the implementation of these tools (i.e., an environment composed of these tools) is systematically being derived from the formal specifications.

Set theoretic approaches to graph grammars

This paper sketches the approaches of a certain branch of graph grammars mainly studied at Erlangen, Osnabruck, Koblenz and Aachen, West Germany. It is named set theoretic, or expression, or algorithmic approach of graph grammars, because its mathematical base is elementary set theory, expressions are used to denote embedding transformations, and the question of applicability and implementation always was regarded of equal importance as theoretical results.

On Integration Mechanisms within a Graph-based Software Development Environment

An integrated software development environment (abbr. SDE) is a comprehensive set of tools which support the activities for developing and maintaining any kind of software document in a software life cycle. These activities may relate to one or to different problem areas (programming in the large, programming in the small, documentation, project management, etc.).

Tool support for the management of design processes in chemical engineering

Design processes in chemical engineering are hard to support. In particular, this applies to conceptual design and basic engineering, in which the fundamental decisions concerning the plant design are performed. The design process is highly creative, many design alternatives are explored, and both unexpected and planned feedback occurs frequently. As a consequence, it is inherently difficult to manage design processes, i.e. to coordinate the effort of experts working on tasks such as creation of flow diagrams, steady-state and dynamic simulations, etc. On the other hand, proper management is crucial because of the large economic impact of the performed design decisions. We present a management system which takes the difficulties mentioned above into account by supporting the coordination of dynamic design processes. The management system equally covers products, activities, and resources, and their mutual relationships. With respect to coverage and integration, and with respect to the dynamics of design processes, the functionality of the management system goes considerably beyond commercial project, document, and workflow management systems.

A Specification Environment for Graph Grammars

Modelling environments (e.g. software development environments) offer tools which build up and maintain complex internal data structures. Therefore, before implementing such tools, it is advisable for the tool developer to formally specify the structure and the operations of these internal data structures. Graph Grammars as an operational specification method have been successfully used for this purpose for many years.

Visual knowledge specification for conceptual design: Definition and tool support

Current CAD tools are not able to support the conceptual design phase, and none of them provides a consistency analysis for sketches produced by architects. This phase is fundamental and crucial for the whole design and construction process of a building. To give architects a better support, we developed a CAD tool for conceptual design and a knowledge specification tool. The knowledge is specific to one class of buildings and it can be reused. Based on a dynamic and domain-specific knowledge ontology, different types of design rules formalize this knowledge in a graph-based form. An expressive visual language provides a user-friendly, human readable representation. Finally, a consistency analysis tool enables conceptual designs to be checked against this formal conceptual knowledge. In this article, we concentrate on the knowledge specification part. For that, we introduce the concepts and usage of a novel visual language and describe its semantics. To demonstrate the usability of our approach, two graph-based visual tools for knowledge specification and conceptual design are explained.

A Software Development Environment based on Graph Technology

This paper describes what we call graph technology and how it is applied to a software development environment (abbreviated SDE) project. This graph technology consists of a careful design of internal representations for software documents as graphs, of a specification of the operations on these graphs induced by activations of environment tools, of the application of certain integration mechanisms on graphs, and of a rather mechanical proceeding how to get a software architecture for the SDE as well as the implementation of the corresponding tools.

On the structure of structure-oriented editors for different applications

The paper describes the experiences we got from the implementation of a series of syntax-directed editors within an incremental and integrated software development environment. The implementation of all editors is based on the same conceptual ideas for specification and realization which is called graph technology. It is specific for the project a part of which we describe here. Using graph technology yields a very similar software architecture for all editors. We explain the development of such a standard architecture and also outline some specific differences resulting from the corresponding application areas.

Software specification using graph grammars

The following paper demonstrates that programmed sequential graph grammars can be used in a systematic proceeding to specify the changes of high level intermediate data structures arising in a programming support environment, in which all tools work in an incremental and syntax-driven mode. In this paper we lay stress upon the way to get the specification rather than on the result of this process. Therefore, we give here some approach to “specification engineering” using graph grammars. This approach is influenced by the syntactical definition of the underlying language for Programming in the Small, the module concept etc. to be supported on one side but also by the idea of the user interface.ZusammenfassungDer folgende Aufsatz zeigt auf, daß programmierte sequentielle Graph-Grammatiken dazu benutzt werden können, die Veränderung hoher Zwischencodes zu spezifizieren, die im Kontext einer Software-Entwicklungsumgebung auftreten, deren Werkzeuge alle inkrementell und syntaxgesteuert arbeiten. Wir legen in diesem Aufsatz mehr Wert auf die Erläuterung einer systematischen Vorgehensweise, um die Spezifikation zu erhalten, als auf die detaillierte Abhandlung der Spezifikation selbst. Somit kann dieses Papier auch als ein Ansatz zu einem „Spezifikations-Engineering” mit Hilfe von Graph-Grammatiken angesehen werden. Der Ansatz wird maßgeblich beeinflußt von der Syntaxdefinition der zugrundeliegenden formalen Sprache für das Programmieren im Kleinen bzw. für das Modulkonzept etc. einerseits und andererseits von der Vorstellung der Form der Benutzerschnittstelle.