Undergraduate Topics in Computer Science Flavio Oquendo Jair Leite Thaís Batista Software Architecture in Action Designing and Executing Architectural Models with SysADL grounded on the OMG SysML Standard Undergraduate Topics in Computer Science Undergraduate Topics in Computer Science (UTiCS) delivers high-quality instructional content for undergraduates studying in all areas of computing and information science. From core foundational and theoretical material to final-year topics and applications, UTiCS books take a fresh, concise, and modern approach and are ideal for self-study or for a one- or two-semester course. The texts are all authoredbyestablishedexpertsintheirfields,reviewedbyaninternationaladvisory board, and contain numerous examples and problems. Many include fully worked solutions. More information about this series at http://www.springer.com/series/7592 Flavio Oquendo Jair Leite (cid:129) í Tha s Batista Software Architecture in Action Designing and Executing Architectural Models with SysADL grounded on the OMG SysML Standard 123 Flavio Oquendo ThaísBatista IRISA Research Institute Department ofComputer Science University of SouthBrittany Federal University of RioGrandedoNorte Vannes Natal, RioGrande doNorte France Brazil Jair Leite Department ofComputer Science Federal University of RioGrandedoNorte Natal, RioGrande doNorte Brazil Series editor IanMackie Advisory Board Samson Abramsky, University of Oxford,Oxford,UK Karin Breitman, Pontifical Catholic University of RiodeJaneiro, RiodeJaneiro,Brazil Chris Hankin, ImperialCollege London,London,UK Dexter Kozen, Cornell University,Ithaca, USA Andrew Pitts, University of Cambridge, Cambridge, UK Hanne Riis Nielson, Technical University of Denmark,Kongens Lyngby,Denmark Steven Skiena, StonyBrookUniversity, StonyBrook, USA Iain Stewart, University of Durham, Durham, UK Additional material tothis bookcanbedownloaded from http://extras.springer.com. ISSN 1863-7310 ISSN 2197-1781 (electronic) Undergraduate Topics inComputer Science ISBN978-3-319-44337-9 ISBN978-3-319-44339-3 (eBook) DOI 10.1007/978-3-319-44339-3 LibraryofCongressControlNumber:2016947944 ©SpringerInternationalPublishingSwitzerland2016 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission orinformationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilar methodologynowknownorhereafterdeveloped. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfrom therelevantprotectivelawsandregulationsandthereforefreeforgeneraluse. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authorsortheeditorsgiveawarranty,expressorimplied,withrespecttothematerialcontainedhereinor foranyerrorsoromissionsthatmayhavebeenmade. Printedonacid-freepaper ThisSpringerimprintispublishedbySpringerNature TheregisteredcompanyisSpringerInternationalPublishingAGSwitzerland Tomybeloved parents,mywifeAndressa and my son Bruno —Flavio Oquendo To my parents Ernani and Marilena and to my daughters Larissa and Cristina —Jair Leite To my father, Juarez da Gama Batista (in memoriam) To my mother, Lygia Vasconcelos Batista To my daughters, Larissa and Cristina —Thais Batista Preface The main goal of this book is to cover a wide spectrum of software architecture modeling techniques using viewpoints to describe the structure, the behavior, and the execution of a software architecture. It is a textbook that covers fundamental approaches of software architecture description, reconciling theory and practice with well-established learning outcomes. The book includes additional resources available at www.sysadl.org such as lecture slides that will be helpful to broader learning and an open-source software tool to support practical exercises. Indeed, in the last two decades, software architecture has become a major dis- ciplineintheintersectionofComputerScienceandSoftwareEngineeringinitsown (like civil architecture compared to civil engineering). Besides, software architec- tureplaysakeyroleforenablingthenextgenerationofsoftware-intensivesystems. Therecognizedimportanceofsoftwarearchitectureledanumberofuniversities to include regular course on software architecture at both graduate and under- graduate levels. However, there is still a lack of textbooks focusing on software architecturemodelingbasedonexplicitlearningoutcomes.Thisbookaimstocover this gap, presenting a systematic approach supported by a software tool to model softwarearchitecturesfromdifferentviewpointsandexecutetheresultingmodelfor validationpurposes,thereforecoveringtheessenceofsoftwarearchitecturedesign. Thisbookisdesignedforteachingsoftwarearchitecturemodelingtechniquesto both graduate and undergraduate students, in order to prepare them to architecting complex software-intensive systems. It is also appealing for practitioners and members of a software development team such as architects, designers, program- mers,projectmanagers,sinceitisstructuredaroundpracticalmodelingapproaches spanning different roles in software development. vii viii Preface This book defines an architecture description language, named SysADL, as a specialization of the OMG SysML standard to software architecture description. SysADL brings together the expressive power of software architecture description languages(ADLs)forarchitecturedescription,withastandardlanguageusedbythe industry (SysML). SysADL is used in all the chapters of this book. Vannes, France Flavio Oquendo Natal, Brazil Jair Leite Natal, Brazil Thaís Batista Outline Thisbookisstructuredintofourparts.PartIcoversthefundamentalsincludingthe main concepts for modeling software architecture and presents SysADL, derived from the OMG SysML standard. The concepts follow the ISO 42010 reference model. The chapters present the concept of viewpoints and views, and how to describe,usingSysADL,thestructure,thebehaviorandtheexecutionofasoftware architecture. Part II focuses on how to design a software architecture for achieving quality attributes.Eachchaptercoversaspecificqualityattributeandpresentswell-defined approaches to achieve it. PartIII presentshowtoapply software architecture styletodesignarchitectures that meet the quality attributes. Each chapter covers a specific architectural style. Part IV presents how to textually represent software architecture models in complement to the visual notation. Acknowledgments Wewouldliketoacknowledgeallthosewhocontributedforourworkinthisbook. Special thanks to Eduardo Alexandre Ferreira Silva for his valuable support in providing many suggestions, reviewing parts of this book, and implementing the SysADL toolset. We also thank Bruno Carlos da Cunha Costa for his contribution in the initial development of the SysADL toolset, and Everton Ranielly de Sousa Cavalcante for reviewing parts of this book. We would like to thank CNPq—the Brazilian Council for Scientific and Technological Development—for the financial support for our research collabora- tion that contributed to allow us writing this book. We would like to thank the staff of Springer for their support, especially Beverley Ford and James Robinson. Finally,we thank ourfamiliesandfriendsfor theirencouragementandsupport. ix Contents Part I Fundamentals 1 Introduction to Software Architecture... .... .... .... ..... .... 3 1.1 The Concept of Software Architecture ... .... .... ..... .... 3 1.2 Language for Modeling Software Architecture. .... ..... .... 5 1.2.1 Why Conceiving SysADL. .... .... .... ..... .... 6 1.2.2 Introducing SysML for SysADL.... .... ..... .... 7 1.2.3 SysADL as a Specialization of SysML for Architecture Modeling. .... .... .... ..... .... 8 1.3 Designing Software Architecture with SysADL .... ..... .... 9 1.3.1 Describing Software Architectures... .... ..... .... 10 1.3.2 Designing Quality-Based Software Architectures. .... 10 1.3.3 Designing Style-Based Software Architectures .. .... 10 1.3.4 Textually Representing Software Architectures .. .... 10 1.4 Running Case Study to Illustrate Software Architecture... .... 11 1.5 Summary .... .... ..... .... .... .... .... .... ..... .... 11 Further Reading .... .... ..... .... .... .... .... .... ..... .... 12 References. .... .... .... ..... .... .... .... .... .... ..... .... 12 2 Viewpoints for Describing Software Architectures . .... ..... .... 13 2.1 The Definition of Software Architecture.. .... .... ..... .... 13 2.2 Software Architecture Description .. .... .... .... ..... .... 14 2.3 Concepts for Describing Software Architecture .... ..... .... 17 2.4 Architectural Viewpoints and Views. .... .... .... ..... .... 21 2.4.1 Architectural Viewpoints.. .... .... .... ..... .... 21 2.4.2 Architectural Views.. .... .... .... .... ..... .... 23 2.5 Summary .... .... ..... .... .... .... .... .... ..... .... 24 Further Reading .... .... ..... .... .... .... .... .... ..... .... 25 Reference . .... .... .... ..... .... .... .... .... .... ..... .... 25 xi