Foreword by Professor Neil Maiden

ix

Preface

xi

     1.1      Why projects fail

2

     1.2      Aligning IT with business – speaking a common language

4

                1.2.1        Models

6

     1.3      What is service oriented architecture?

9

                1.3.1        The real user

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     1.4      Business drivers for SOA

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     1.5      Technology drivers

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     1.6      Benefits, pitfalls and prospects

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                1.6.1        Pitfalls

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                1.6.2        Post-SOA benefits

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     1.7      Migration strategies

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     1.8      Summary

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     1.9      Bibliographical notes

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2  Architecture – Objects, Components, Services

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     2.1      What is architecture?

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                2.1.1        Architecture as high level structure

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                2.1.2        Architecture as design rationale or vision

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                2.1.3        Architecture and reuse

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     2.2      Architecture through the ages

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     2.3      Objects and components

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                2.3.1        Components for flexibility

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                2.3.2        Large-scale connectors

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                2.3.3        How services relate to components

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     2.4      Architecture and SOA

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     2.5      Stateless services

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     2.6      Principles for developing, maintaining and exploiting a SOA

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     2.7      Summary

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     2.8      Bibliographical notes

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3  Approaches to Requirements Engineering

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     3.1      Conventional approaches

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                3.2.1        Approaches based on human factors

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     3.2      Classic requirements versus use cases

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                3.2.1        UML basics

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                3.2.2        Use case models

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                3.2.3        Formulating requirements

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     3.3      Problem Frames

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     3.4      Requirements and business rules

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     3.5      Establishing and prioritizing the business objectives

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     3.6      Soft techniques for requirements elicitation

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                3.6.1        Using interviewing techniques

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                3.6.2        Repertory grids

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                3.6.3        Hierarchical task analysis

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                3.6.4        Object discovery techniques

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     3.7      Summary

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     3.8      Bibliographical notes

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4  Business Process Modelling

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     4.1      The origins of need for business process modelling

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     4.2      Business process modelling in a nutshell

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     4.3      UML activity diagrams

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     4.4      BPMN

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                4.4.1 Fundamental business process modelling patterns

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                4.4.2 A practical example

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     4.5      WS-BPEL

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     4.6      Orchestration and choreography

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     4.7      Process algebra and Petri nets

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     4.8      The human side of business process management

144

     4.9      Summary

145

     4.10    Bibliographical notes

146

5  Catalysis Conversation Analysis

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     5.1      What is a business process?

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     5.2      Conversations

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     5.3      Conversation stereotypes and scripts

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                5.3.1        Handling exceptions

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     5.4      Conversations as components

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     5.5      Contracts and goals

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     5.6      Conversations, collaborations and services

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     5.7      Checking model consistency

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     5.8      Summary

171

     5.9      Bibliographical notes

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6  Models of large enterprises

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     6.1      Business process modelling and SOA in the large

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     6.2      Business rules in the mission grid

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     6.3      The mission grid as a roadmap for SOA

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     6.4      Other approaches

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     6.5      Summary

186

     6.6      Bibliographical notes

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7 Specification modelling

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     7.1      From requirements to specification

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     7.2      Some problems with the conventional approach to use cases

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                7.2.1        Overemphasis on functional decomposition

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                7.2.2        Lack of clear definition

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                7.2.3        Controller objects

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                7.2.4        Use cases and scenarios

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                7.2.5        Essential or generic use cases

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                7.2.6        Atomicity

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                7.2.7        Level of abstraction

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                7.2.8        Exception handling

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     7.3      Describing boundary conversations or use cases

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     7.4      Establishing the type model

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                7.4.1        State models

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     7.5      Finding services from state models

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                7.5.1        Cartooning using agents or coördinators

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     7.6      Finding business rules

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     7.7      Ontology, type models and business rules

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                7.7.1        Rules and rule chaining

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     7.8      Documenting the specification

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     7.9      Associations, rules and encapsulation

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                7.9.1        Integrity rules rulesets and encapsulation

226

     7.10    Summary

229

     7.11    Bibliographical notes

231

8  Standards

233

     8.1      BPM standards

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     8.2      Web Services standards

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     8.3      Other miscellaneous standards

236

     8.4      Bibliographical notes

240

Appendices

A  Requirements engineering and specification patterns

241

B  The fundamental concepts of service oriented architecture

297

References and bibliography

307

Index

313