This book is intended for anyone who plans, designs and implements software systems, for anyone who is involved with quality assurance, and hence for anyone who is interested in the practicability of modern concepts, methods and tools in the software development process. The book aims at software engineers and at students with specialized interests in the area of software engineering. The reader is expected to be familiar with the fundamental concepts of software engineering. In writing the book, the authors tap years of experience in industrial projects and research work in the development of methods and tools that support the software development process. Perhaps now more than ever, the buzzword "software crisis" serves to alert us that software systems are often error-prone, that significant diffi­ culties arise in mastering complexity in the production of software systems, and that the acceptance and adequacy of software products is significantly lower than is the case with other technical products. The following goals have been suggested for the improvement of the software development process: . exact fulfillment of user requirements . increased reliability and robustness . greater modularity of both the development process and the product . simple and adequate operation, i. e. , better ergonomics . easy maintainability and extensibility . cost-effective portability . increased reusability of software components . reduced costs for production, operation and maintenance VI Preface Research and development work in the area of software engineering has in­ creased dramatically in recent years.

Inhalt

I Prototyping-Oriented Software Development: Paradigms, Concepts, and Tools.- 1 Paradigms for Software Development.- 1.1 The Sequential Life-Cycle Paradigm.- 1.1.1 The Phases of the Sequential Software Life Cycle.- 1.1.2 The Thought Model behind the Sequential Life-Cycle Paradigm.- 1.1.3 Advantages and Disadvantages of the Sequential Life-Cycle Paradigm.- 1.2 The Prototyping Paradigm.- 1.2.1 Approaches to Prototyping.- 1.2.2 The Prototyping-Oriented Software Life Cycle.- 1.2.3 Advantages and Disadvantages of the Prototyping Paradigm.- 1.3 The Exploratory Programming Paradigm.- 1.3.1 Software Development Using the Exploratory Programming Paradigm.- 1.3.2 Advantages and Disadvantages of the Exploratory Programming Paradigm.- 1.4 The Operational Paradigm.- 1.4.1 Software Development Using the Operational Paradigm.- 1.4.2 Advantages and Disadvantages of the Operational Paradigm.- 2 Concepts and Tools for Prototyping.- 2.1 User Interface Prototyping.- 2.1.1 Concepts for User Interface Prototyping.- 2.1.2 Selection Criteria for User Interface Prototyping Tools.- 2.1.3 DICE-a Tool Example.- 2.2 Concepts for Software Architecture Prototyping.- 2.2.1 Prototyping of Module-Oriented Software Architectures.- 2.2.1.1 How to Prototype Module-Oriented Software Architectures.- 2.2.1.2 Selection Criteria for Architecture Prototyping Tools.- 2.2.1.3 SCT-a Tool Example.- 2.2.2 Prototyping of Concurrent Systems with Petri Nets.- 2.2.2.1 PrT-Nets.- 2.2.2.2 How to Prototype Distributed Systems with PrTNets.- 2.2.2.3 Selection Criteria for Tools Supporting Prototyping with PrT-Nets.- 2.2.2.4 SPECS-a Tool Example.- 2.3 Prototyping of Information Systems.- 2.3.1 Prototyping with 4th Generation Systems.- 2.3.1.1 How to Prototype with 4th Generation Systems.- 2.3.1.2 Selection Criteria for 4th-Generation Systems.- 2.3.1.3 4th Dimension-a Tool Example.- 2.3.2 Prototyping with Hypertext Systems.- 2.3.2.1 How to Prototype with Hypertext Systems.- 2.3.2.2 Selection Criteria for Hypertext Systems.- 2.3.2.3 HyperCard-a Tool Example.- 3 Concepts and Tools for Exploratory Programming.- 3.1 Programming Languages.- 3.2 Programming Environments.- 3.2.1 Concepts Underlying Programming Environments.- 3.2.2 Smalltalk-80-a Tool Example.- 3.3 Reuse of Design Information and Code.- 3.3.1 Concepts for Reuse of Design Information and Code.- 3.3.2 ET++-a Tool Example.- 4 Additional Aspects of Prototyping.- II TOPOS A Toolset for Prototyping-Oriented Software Development.- 5 Overview of TOPOS.- 5.1 Basic Requirements on TOPOS.- 5.2 Basic Concepts Underlying TOPOS.- 5.3 Overall Structure of TOPOS.- 6 The TOPOS Component Management Tool (CMT).- 6.1 Concepts Underlying CMT.- 6.2 Application of CMT.- 7 The TOPOS User Interface Prototyping Environment DICE.- 7.1 Concepts Underlying DICE.- 7.2 Application of DICE.- 8 The TOPOS Exploratory Programming Environment.- 8.1 Concepts Underlying SCT.- 8.2 The Architecture of the Exploratory Programming Environment.- 8.3 Implementor.- 8.3.1 Concepts Underlying the Implementor.- 8.3.2 Application of the Implementor.- 8.4 Browser.- 8.4.1 Concepts Underlying the Browser.- 8.4.2 Application of the Browser.- 8.5 Workspace Manager.- 8.5.1 Concepts Underlying the Workspace Manager.- 8.5.2 Application of the Workspace Manager.- 8.6 Simulator.- 8.6.1 Concepts Underlying the Simulator.- 8.6.2 Application of the Simulator.- 9 The TOPOS Tool Integration Mechanism.- 9.1 Concepts for Tool Integration.- 9.2 Integration of Tools into TOPOS.- 9.3 Examples of Tool Integration.- 10 How to Use TOPOS for Prototyping-Oriented Software Development.- 10.1 General Aspects.- 10.2 Application Scenario.- 11 Experience with and Implications of TOPOS.