Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró: Style-Based Modeling and Refinement of Service-Oriented Architectures. In Software and Systems Modeling, vol. 5, no. 2, pp. 187-207 (2005)
Show Bibtex | Show Abstract | URL

@article{Baresi2005, author = {Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró}, title = {Style-Based Modeling and Refinement of Service-Oriented Architectures}, journal = {Software and Systems Modeling}, year = {2005}, volume = {5}, number = {2}, pages = {187-207} }

Service-oriented architectures (SOA) provide a flexible and dynamic platform for implementing business solutions. In this paper, we address the modeling of such architectures by refining business-oriented architectures, which abstract from technology aspects, into service-oriented ones, focusing on the ability of dynamic reconfiguration (binding to new services at run-time) typical for SOA. The refinement is based on conceptual models of the platforms involved as architectural styles, formalized by graph transformation systems. Based on a refinement relation between abstract and platform-specific styles we investigate how to realize business-specific scenarios on the SOA platform by automatically deriving refined, SOA-specific reconfiguration scenarios.

Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró: Style-Based Refinement of Dynamic Software Architectures. In Proceedings of the conference on Software Architecture (WICSA 2004), Oslo (Norway). IEEE Computer Society (Washington, DC, USA), pp. 155--166 (2004) 12-15 June 2004
Show Bibtex | Show Abstract | DOI

@inproceedings{Baresi2004, author = {Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró}, title = {Style-Based Refinement of Dynamic Software Architectures}, booktitle = {Proceedings of the conference on Software Architecture (WICSA 2004), Oslo (Norway)}, year = {2004}, pages = {155--166}, address = {Washington, DC, USA}, publisher = {IEEE Computer Society}, note = {12-15 June 2004} }

In this paper, we address the correct refinement of abstract architectural models into more platformspecific representations. We consider the challenging case of dynamic architectures which can perform runtime reconfigurations. For this purpose, the underlying platform has to provide the necessary reconfiguration mechanisms. To conceptually model such platforms including provided reconfiguration mechanisms, we use architectural styles formalized by graph transformation rules. Based on formal refinement relations between abstract and platform-specific styles, we can then investigate how to realize business-specific scenarios on a certain platform by automatically deriving refined, platform-specific reconfiguration scenarios.

Reiko Heckel and Jochen Küster and Sebastian Thöne and Hendrik Voigt: Towards Consistency of Web Service Architectures. In Proceedings of the 7th World Multiconference on Systemics, Cybernetics, and Informatics (SCI 2003), Orlando, FL (USA). (2003)
Show Bibtex | Show Abstract

@inproceedings{HKTV03, author = {Reiko Heckel and Jochen Küster and Sebastian Thöne and Hendrik Voigt}, title = {Towards Consistency of Web Service Architectures}, booktitle = {Proceedings of the 7th World Multiconference on Systemics, Cybernetics, and Informatics (SCI 2003), Orlando, FL (USA)}, year = {2003}, month = {July} }

Web services are self-descriptive software components which can automatically be discovered and engaged, together with other web components, to complete tasks over the Internet. The integration of Web services entails consistency problems which can best be solved at the level of models. In this paper, we discuss an approach to model-based consistency management for component-based architectures and its application to Web service architectures.

Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró: Modeling and validation of service-oriented architectures: application vs. style. In Proceedings of the European Software Engineering Conference and ACM SIGSOFT Symposium on the Foundations of Software Engineering (ESEC/FSE 2003), Helsinki (Finland). ACM Press (New York, NY, USA), pp. 68--77 (2003)
Show Bibtex | Show Abstract | DOI

@inproceedings{Baresi2003, author = {Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró}, title = {Modeling and validation of service-oriented architectures: application vs. style}, booktitle = {Proceedings of the European Software Engineering Conference and ACM SIGSOFT Symposium on the Foundations of Software Engineering (ESEC/FSE 2003), Helsinki (Finland)}, year = {2003}, pages = {68--77}, address = {New York, NY, USA}, month = {September}, publisher = {ACM Press} }

Most applications developed today rely on a given middleware platform which governs the interaction between components, the access to resources, etc. To decide, which platform is suitable for a given application (or more generally, to understand the interaction between application and platform), we propose UML models of both the architectural style of the platform and the application scenario. Based on a formal interpretation of these as graphs and graph transformation systems, we are able to validate the consistency between platform and application. We exemplify the approach for platforms realizing the service-oriented architectural style and a supply chain management system as application scenario. Besides, we demonstrate the potential of model checking for graph transformation systems for answering the above consistency question.

Ralph Depke and Gregor Engels and Matthew Langham and Björn Lütkemeier and Sebastian Thöne: Process-Oriented, Consistent Integration of Software Components. In Proceedings of the conference on Prolonging Software Life: Development and Redevelopment (COMPSAC 2002), Oxford (England). IEEE Computer Society (Washington, DC, USA), pp. 13--18 (2002) COMPSAC '02: Proceedings of the 26th International Computer Software and Applications Conference on Prolonging Software Life: Development and Redevelopment
Show Bibtex | Show Abstract | DOI

@inproceedings{Depke2002, author = {Ralph Depke and Gregor Engels and Matthew Langham and Björn Lütkemeier and Sebastian Thöne}, title = {Process-Oriented, Consistent Integration of Software Components}, booktitle = {Proceedings of the conference on Prolonging Software Life: Development and Redevelopment (COMPSAC 2002), Oxford (England)}, year = {2002}, pages = {13--18}, address = {Washington, DC, USA}, month = {August}, publisher = {IEEE Computer Society}, note = {COMPSAC '02: Proceedings of the 26th International Computer Software and Applications Conference on Prolonging Software Life: Development and Redevelopment} }

The integration of software components becomes a more and more important issue in software engineering. Process-oriented approaches should provide automated information processes. Therefore, the software components have to be integrated in a consistent way, i.e., their export interfaces have to be respected by the importing components. Furthermore, the type system of component interfaces has to support a tunable degree of freedom. This allows the insertion of components with interfaces of restricted but sufficient degree of compatibility. In this paper, we develop a concept for consistent and flexible integration of components. We present a process modeling language that combines UML and XML in order to support consistent, flexible, and executable processes. Finally, we provide a formalization of the proposed component type system.

Björn Lütkemeier and Sebastian Thöne: Prozessorientierte Integration von Softwarekomponenten durch XML-basierte Workflow-Modelle. In Proceedings of the Fachwissenschaftlicher Informatik-Kongress (Informatiktage 2001), Bad Schussenried (Germany). Konradin-Verlag (2001)
Show Bibtex

@inproceedings{Lütkemeier01, author = {Björn Lütkemeier and Sebastian Thöne}, title = {Prozessorientierte Integration von Softwarekomponenten durch XML-basierte Workflow-Modelle}, booktitle = {Proceedings of the Fachwissenschaftlicher Informatik-Kongress (Informatiktage 2001), Bad Schussenried (Germany)}, year = {2001}, month = {November}, publisher = {Konradin-Verlag} }

Sebastian Thöne: Entwicklung eines Übersetzers von Nachrichtenaustauschformaten für Bankselbstbedienungssysteme in XML-Formate. In Proceedings of the Informatiktage 2000, Bad Schussenried (Germany). Konradin-Verlag (Leinfelden - Echterdingen) (2000)
Show Bibtex | Show Abstract | URL

@inproceedings{Thoene00, author = {Sebastian Thöne}, title = {Entwicklung eines Übersetzers von Nachrichtenaustauschformaten für Bankselbstbedienungssysteme in XML-Formate}, booktitle = {Proceedings of the Informatiktage 2000, Bad Schussenried (Germany)}, year = {2000}, address = {Leinfelden - Echterdingen}, month = {October }, publisher = {Konradin-Verlag} }

Banken verwenden heute noch überwiegend binäre Nachrichtenaustauschformate zwischen Bankselbstbedienungssystemen und zentralen Rechnern, aber aufgrund zahlreicher Vorteile sollen in Zukunft XML-basierte Formate eingesetzt werden. Damit entsteht das Problem der Übersetzung zwischen binären und XML-Formaten. Da unterschiedliche Ausgangsformate in ein einheitliches Zielformat übersetzt werden sollen, müssen entstehende XML-Zwischenformate in das Zielformat umgesetzt werden. Daraus entsteht die interessante Frage, wie Transformationen von XML-Dokumenten spezifiziert und erzeugt werden können. In der Arbeit wurde ein Konzept zur Lösung der praxisbezogenen Problemstellung entwickelt. Ziel der Arbeit war vor allem, Vorschläge für die Übersetzung von binären Formaten in XML-Dokumente und für die Transformation von XML-Dokumenten zu erarbeiten. Im Anschluß sollten die Konzepte in eine Implementierung umgesetzt werden. Für die Umwandlung von binären Austauschformaten in Bankselbstbedienungssystemen wurde ein leicht erweiterbarer Übersetzer in ein XML-Zwischenformat entwickelt. Für die Umwandlung in das XML-Zielformat wurde ein Konzept entwickelt, XML-Dokumente durch XSL-Transformationen umzustrukturieren. Derartige Transformationen werden nach einer neu entwickelten Methode in neuartigen XML-Dokumenten spezifiziert. Aus den Spezifikationsdokumenten werden XSLT-Regeln generiert, die von vorhandenen XSLT-Prozessoren für die Transformation von XML-Dokumenten verwendet werden. Das vorgeschlagene Konzept wurde implementiert und damit die gestellte Aufgabe vollständig gelöst.

Ralph Depke and Matthew Langham and Björn Lütkemeier and Sebastian Thöne: Ein Konzept zur Generierung von XSL-Transformationen und dessen Anwendung bei Bankselbstbedienungssystemen. In Proceedings of the Net.ObjectDays (2000), Erfurt (Germany). (2000)
Show Bibtex | Show Abstract

@inproceedings{Depke02, author = {Ralph Depke and Matthew Langham and Björn Lütkemeier and Sebastian Thöne}, title = {Ein Konzept zur Generierung von XSL-Transformationen und dessen Anwendung bei Bankselbstbedienungssystemen}, booktitle = {Proceedings of the Net.ObjectDays (2000), Erfurt (Germany)}, year = {2000}, month = {October } }

Die Transformation von XML-Dokumenten mit XSLTRegeln ist von großer praktischer Relevanz. Der Aufwand für die Erstellung der Regeln wächst allerdings mit der Größe der ineinander zu überführenden Dokumentformate und der Komplexität der Transformation. Mit der wachsenden Menge von Regeln wird die Übersetzung auch immer weniger nachvollziehbar. Die in diesem Artikel vorgeschlagene Spezifikation von XSLTransformationen und die nachfolgende Generierung von XSLT-Regeln vereinfacht die Erstellung von Übersetzern und bildet gleichfalls eine besser verständliche Dokumentation der Übersetzungsvorschrift. Die praktische Relevanz des Verfahrens zeigt sich zum Beispiel bei der Konvertierung von Austauschformaten in Bankselbstbedienungssystemen.

Reiko Heckel and Sebastian Thöne: Behavioral Refinement of Graph Transformation-Based Models. In Proceedings of the workshop on Software Evolution through Transformations (SETra 2004), Rome (Italy). Elsevier (Amsterdam, The Netherlands), vol. 127, no. 3, pp. 101--111 (2005) ICGT 2004
Show Bibtex | Show Abstract | URL | DOI

@inproceedings{Heckel2005, author = {Reiko Heckel and Sebastian Thöne}, title = {Behavioral Refinement of Graph Transformation-Based Models}, booktitle = {Proceedings of the workshop on Software Evolution through Transformations (SETra 2004), Rome (Italy)}, year = {2005}, volume = {127}, number = {3}, pages = {101--111}, address = {Amsterdam, The Netherlands}, publisher = {Elsevier}, note = {ICGT 2004} }

Model-driven software engineering requires the refinement of abstract models into more concrete, platform-specific ones. To create and verify such refinements, behavioral models capturing reconfiguration or communication scenarios are presented as instances of a dynamic meta-model, i.e., a typed graph transformation system specifying the concepts and basic operations scenarios may be composed of. Possible refinement relations between models can now be described based on the corresponding meta-models. In contrast to previous approaches, refinement relations on graph transformation systems are not defined as fixed syntactic mappings between abstract transformation rules and, e.g., concrete rule expressions, but allow for a more loose, semantically defined relation between the transformation systems, resulting in a more flexible notion of refinement.

Reiko Heckel and Sebastian Thöne: Behavior-Preserving Refinement Relations between Dynamic Software Architectures. In Proceedings of the workshop on Algebraic Development Techniques (WADT 2004), Barcelona (Spain). Springer (Berlin/Heidelberg), LNCS, vol. 3423, pp. 1--27 (2004)
Show Bibtex | Show Abstract

@inproceedings{Heckel2004a, author = {Reiko Heckel and Sebastian Thöne}, title = {Behavior-Preserving Refinement Relations between Dynamic Software Architectures}, booktitle = {Proceedings of the workshop on Algebraic Development Techniques (WADT 2004), Barcelona (Spain)}, year = {2004}, volume = {3423}, series = {LNCS}, pages = {1--27}, address = {Berlin/Heidelberg}, publisher = {Springer} }

In this paper, we address the refinement of abstract architectural models into more platform-specific representations. For each level of abstraction, we employ an architectural style covering structural restrictions on component configurations as well as supported communication and reconfiguration operations. Architectural styles are formalized as graph transformation systems with graph transformation rules defining the available operations. Architectural models are given as graphs to which one can directly apply the transformation rules in order to simulate operations and their effects. In addition to previous work, we include process descriptions into our architectural models in order to control the communication and reconfiguration behavior of the components. The execution semantics of these processes is also covered by graph transformation systems. We propose a notion of refinement which requires the preservation of both structure and behavior at the lower level of abstraction. Based on formal refinement relationships between abstract and platform-specific styles, we can use model checking techniques to verify that abstract scenarios can also be realized in the platform-specific architecture.

Reiko Heckel and Marc Lohmann and Sebastian Thöne: Towards a UML Profile for Service-Oriented Architectures. In Proceedings of the Workshop on Model Driven Architecture: Foundations and Applications (MDAFA 2003), Enschede (The Netherlands). University of Twente (Enschede, The Netherlands), CTIT Technical Report, vol. TR–CTIT–03–27, pp. 115--120 (2003)
Show Bibtex | URL

@inproceedings{HLT03MDAFA, author = {Reiko Heckel and Marc Lohmann and Sebastian Thöne}, title = {Towards a UML Profile for Service-Oriented Architectures}, booktitle = {Proceedings of the Workshop on Model Driven Architecture: Foundations and Applications (MDAFA 2003), Enschede (The Netherlands)}, year = {2003}, volume = {TR–CTIT–03–27}, series = {CTIT Technical Report}, pages = {115--120}, address = {Enschede, The Netherlands}, month = {June }, publisher = {University of Twente} }

Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró: Modeling and Analysis of Architectural Styles Based on Graph Transformation. In Proceedings of the 6th ICSE Workshop on Component Based Software Engineering: Automated Reasoning and Prediction (CBSE 2003), Portland, OR (USA). Carnegie Mellon University (USA), and Monash University (Australia), pp. 67--72 (2003)
Show Bibtex

@inproceedings{Baresi2003a, author = {Luciano Baresi and Reiko Heckel and Sebastian Thöne and Dániel Varró}, title = {Modeling and Analysis of Architectural Styles Based on Graph Transformation}, booktitle = {Proceedings of the 6th ICSE Workshop on Component Based Software Engineering: Automated Reasoning and Prediction (CBSE 2003), Portland, OR (USA)}, year = {2003}, pages = {67--72}, month = {May 3-4}, publisher = {Carnegie Mellon University (USA), and Monash University (Australia)} }

Sebastian Thöne and Ralph Depke and Gregor Engels: Process-Oriented, Flexible Composition of Web Services with UML. In Proceedings of the International Workshop on Conceptual Modeling Approaches for e-Business: A Web Service Perspective (eCOMO 2002), Tampere (Finland). Springer (Berlin/Heidelberg), LNCS, vol. 2784, pp. 390--401 (2002)
Show Bibtex | Show Abstract

@inproceedings{Thone2002, author = {Sebastian Thöne and Ralph Depke and Gregor Engels}, title = {Process-Oriented, Flexible Composition of Web Services with UML}, booktitle = {Proceedings of the International Workshop on Conceptual Modeling Approaches for e-Business: A Web Service Perspective (eCOMO 2002), Tampere (Finland)}, year = {2002}, volume = {2784}, series = {LNCS}, pages = {390--401}, address = {Berlin/Heidelberg}, month = {October}, publisher = {Springer} }

The composition of elementary web services to larger-scale services has become an important means to enhance e-business collaborations. If such composite web services can also integrate legacy components that are not yet provided as web services, the number of possible compositions is increased. Following a process-oriented approach, the compositions can be described as control- and data-flow between available web services and components. This paper discusses the Business Process Execution Language for Web Services (BPEL4WS), an existing service composition language, and proposes UML-WSC as an alternative, visual language. For the advanced description of service interfaces, UML-WSC extends the type system of the established Web Service Definition Language (WSDL).

Gregor Engels and Alexander Förster and Reiko Heckel and Sebastian Thöne: Process Modeling using UML. In M. Dumas, W. van der Aalst, A. ter Hofstede (eds.): Process-Aware Information Systems. pp. 85-117 Wiley (New York, NY) (2005)
Show Bibtex | Show Abstract

@incollection{Engels2005, author = {Gregor Engels and Alexander Förster and Reiko Heckel and Sebastian Thöne}, title = {Process Modeling using UML}, booktitle = {Process-Aware Information Systems}, publisher = {Wiley}, year = {2005}, pages = {85-117}, address = {New York, NY} }

This chapter provides an introduction to the Unified Modeling Language (UML), a widely adopted object-oriented modeling standard, and shows how the language can be applied to (business) process modeling. As major perspectives of process modeling with UML 2.0, the chapter covers control flow, data objects and object flow, organizational structure, business partner interactions, and system-specific process models. Various types of UML diagrams are presented with a special focus on how these diagrams fit together and complement each other to form a coherent view of a process. Moreover, a running example is used throughout the chapter to illustrate the different facets of a process model.

Sebastian Thöne: Dynamic Software Architectures: A Style-Based Modeling and Refinement Technique with Graph Transformations. Type: Phd Thesis (2005)
Show Bibtex | Show Abstract | URL | DOI

@phdthesis{Thoene2005, author = {Sebastian Thöne}, title = {Dynamic Software Architectures: A Style-Based Modeling and Refinement Technique with Graph Transformations}, year = {2005}, month = {January} }

A good architectural design allows to capture the overall complexity of large, distributed systems at a higher level of abstraction. This is especially important for reconfigurable systems where the architectural configuration is subject to (constant) changes at runtime. When designing such a dynamic architecture, the software architect has to bring the functional business requirements and the available communication and reconfiguration mechanisms of the intended target platform in line. As it is a complex task to incorporate these often diverging requirements into the architectural model, we propose a stepwise approach similar to the MDA initiative. We start with a platformindependent model capturing the business requirements and add platform-specific details in a later step. For each level of platform abstraction and associated platform, we define an architectural style which describes the characteristics of the platform. This way, conformance to the architectural style entails consistency with the underlying platform. Besides run-time configurations of components and connections, architectural models also comprise the description of processes that control the communication and reconfiguration behavior. To provide operational semantics, architectural models are formalized as graphs, and architectural styles are formalized as graph transformation systems. UML is added as high-level modeling language on top, and profiles are used to adapt UML to certain architectural styles. Due to the stepwise procedure, we also have to ensure the mutual consistency between models at different levels of abstraction. For this purpose, we define formal criteria which require that both structural and behavioral properties are preserved at the lower level of abstraction. Based on refinement relationships between abstract and platform-specific architectural styles, an algorithm allows to verify that all abstract, business-level behavior can also be realized in the platformspecific architecture and that no new behavior is added. These refinement techniques facilitate a stepwise, platform-consistent development of dynamic software architectures.

Björn Lütkemeier and Sebastian Thöne: Prozessorientierte Integration von Softwarekomponenten durch XML-basierte Workflow-Modelle. Type: Diploma Thesis, diplomathesis (Paderborn) (2001)
Show Bibtex

@mastersthesis{Luetkemeier2001, author = {Björn Lütkemeier and Sebastian Thöne}, title = {Prozessorientierte Integration von Softwarekomponenten durch XML-basierte Workflow-Modelle}, year = {2001}, type = {diplomathesis}, address = {Paderborn} }