SOA with Java

Thomas Erl is a top-selling IT author, founder of Arcitura Education, editor of the Service Technology Magazine, and series editor of the Prentice Hall Service Technology Series from Thomas Erl. With more than 175,000 copies in print worldwide, his books have become international bestsellers and have been formally endorsed by senior members of major IT organizations, such as IBM, Microsoft, Oracle, Intel, Accenture, IEEE, HL7, MITRE, SAP, CISCO, HP, and many others. As CEO of Arcitura Education Inc. and in cooperation with CloudSchool.com and SOASchool.com, Thomas has led the development of curricula for the internationally recognized Cloud Certified Professional (CCP) and SOA Certified Professional (SOACP) accreditation programs, which have established a series of formal, vendor-neutral industry certifications obtained by thousands of IT professionals around the world. Thomas has toured more than 20 countries as a speaker and instructor and regularly participates in international conferences, including Service Technology Symposium and Gartner events. More than 100 articles and interviews by Thomas have been published in numerous publications, including The Wall Street Journal and CIO Magazine. Andre Tost works as a Senior Technical Staff Member and Software Architect in IBM’s Software Group. He is currently helping to develop and evolve the new PureApplication System cloud platform. Previously, Andre spent 10 years as an SOA consultant for IBM, leading large SOA transformation projects with clients worldwide. His specific focus was on SOA governance and middleware integration using enterprise service bus technology. Andre has co-authored several technical books and has published many articles on SOA and related topics. He is also a frequent conference speaker. Originally from Germany, he now works and lives in Rochester, Minnesota. He likes to watch, coach and play soccer whenever his busy schedule allows. Andre has a degree in Electrical Engineering from Berufsakademie Stuttgart, Germany. Satadru Roy is a Consultant Architect who has designed and built large-scale, distributed systems using Java-based technologies for the last two decades. In that time he has worked as a product engineer and services consultant at Java infrastructure software vendors such as BEA Systems, Sun Microsystems, and Oracle Inc. He currently helps customers build mobile and cloud-hosted applications where he alternates between wearing architect and development manager hats, while his main areas of focus are API design and lightweight integration using agile development methodologies. Satadru is also immersing himself in the growing eco-system of the Scala platform and believes they will play increasingly important roles in future cloud and Big Data applications. He holds a Masters degree in Engineering from Indian Institure of Science. Philip Thomas is an IT Architect in IBM’s Software Group. During his time in the technology sector, he has worked across industries and geographies with a range of organizations as a consultant on technology strategy and on the architecture, design, and implementation of a broad variety of solutions. His expertise spans a number of areas including Java/JEE, SOA, transaction processing systems, messaging/integration middleware, business process management, information management systems, and business analytics. He currently specializes in Big Data and analytics, based out of the UK. Prior to joining IBM in 2000, Phil trained as a physicist and holds a Ph.D. in experimental high-temperature superconductivity awarded by the University of Birmingham.

Foreword     xix
CHAPTER 1: Introduction     1
1.1 About This Book     2
Objectives of This Book     2
Who This Book Is For     2
What This Book Does Not Cover     3
1.2 Prerequisite Reading     3
How This Book Is Organized     4
1.3 How Principles and Patterns Are Used in This Book     7
1.4 Symbols and Figures     7
1.5 Additional Information     7
Updates, Errata, and Resources (www.servicetechbooks.com)      8
Referenced Specifications (www.servicetechspecs.com)      8
The Service Technology Magazine (www.servicetechmag.com)      8
Service-Orientation (www.serviceorientation.com)      8
What Is REST? (www.whatisrest.com)      8
What Is Cloud? (www.whatiscloud.com)      8
SOA and Cloud Computing Design Patterns (www.soapatterns.org, www.cloudpatterns.org)      8
SOA Certified (SOACP) Professional (www.soaschool.com)      9
Cloud Certified Professional (CCP) (www.cloudschool.com)      9
Big Data Science Certified Professional (BDSCP) (www.bigdatascienceschool.com)      9
Notification Service     9
CHAPTER 2: Case Study Examples     11
2.1 How Case Study Examples Are Used     12
Style Characteristics     12
Relationship to Abstract Content     12
Code Samples     12
2.2 Case Study Background: NovoBank     13
Technical Infrastructure     13
Automation Solutions     13
Business Obstacles and Goals     14
Future IT Roadmap     15
1. Build Reusable Business Services     15
2. Consolidate Information     16
3. Improve Channel Experience     16
4. Build Services Infrastructure     16
2.3 Case Study Background: SmartCredit Co     16
Technical Infrastructure     17
Automation Solutions     17
Business Goals     17
Future IT Roadmap     18
PART I: FUNDAMENTALS
CHAPTER 3: Fundamental SOA Concepts     21
3.1 Basic Terminology and Concepts     22
Service-Oriented Computing     22
Service-Orientation     24
Service-Oriented Architecture (SOA)      27
SOA Manifesto     28
Services     29
Cloud Computing     29
IT Resources     30
Service Models     30
Agnostic Logic and Non-Agnostic Logic     31
Service Inventory     32
Service Portfolio     32
Service Candidate     33
Service Contract     33
Service-Related Granularity     34
Service Profiles     35
SOA Design Patterns     36
3.2 Further Reading     38
CHAPTER 4: Basic Java Distributed Technologies     39
4.1 Java Distributed Computing Basics     40
Java SE Architecture     41
Java EE Architecture     41
The Beginning of Java EE     41
Application Packaging and Deployment     44
Deployment Descriptors     44
Java EE Architectural Tiers     45
4.2 Java Distributed Technologies and APIs     46
Java SE APIs     46
RMI     46
RMI / IIOP     47
JNDI     48
JDBC     49
Java EE APIs     49
Contexts and Dependency Injection     49
JTA     50
Java EE Connector Architecture     51
EJB     51
Session EJBs     52
Persistence Entities     53
Service-Orientation Principles and the EJB Model     55
JMS     56
Message-Driven Beans     58
Security in Java EE     58
4.3 XML Standards and Java APIs     59
XML     59
XML Schema Definition     61
XSLT     63
JAXP     63
JAXB     64
4.4 Building Services with Java Components     64
Components as Services     65
Application Protocols     65
Service Contracts     68
Location     68
Operations     69
Messages     69
Further Considerations     70
Components as Services and Service-Orientation     71
Standardized Service Contract     71
Service Loose Coupling     71
Service Abstraction     72
Service Discoverability     72
4.5 Java Vendor Platforms     74
GlassFish Enterprise Server     74
IBM WebSphere Application Server     75
IBM WebSphere Application Server Community Edition     78
Oracle WebLogic Server     79
CHAPTER 5: Web-Based Service Technologies     81
5.1 SOAP-Based Web Services     82
Extensibility of Web Services Standards (WS-*)     88
WS-Addressing     89
SOAP with Attachments (SwA)      90
WS-ReliableMessaging     91
WS-Transaction     92
WS-Security     93
WS-Policy     94
Web Services Distributed Management     95
Common Web Services Middleware     95
Enterprise Service Bus (ESB)      95
Orchestration     97
Management and Monitoring     99
Registries and Repositories     99
Service Construction and Assembly     100
5.2 REST Services     101
HTTP Response Codes     102
Resources and Addresses     103
Service Request     104
Service Response     104
Service Request     104
Service Response     104
HTTP Methods     106
Resource Representations     108
The ACCEPT Header     109
CHAPTER 6: Building Web-Based Services with Java     111
6.1 JAX-WS     112
SAAJ     115
Handlers     118
Web Services Engines and Toolkits     119
JAXR     120
6.2 Java Implementations of WS-* Standards     122
Advanced Web Services Standards and Frameworks     122
Service Component Architecture     123
Spring-WS     124
6.3 JAX-RS     124
Implementing JAX-RS     125
Implementing REST Services     129
Scalability     130
Statelessness     131
Uniform Contract     131
Cacheability     131
Addressability     132
Security     132
REST Service Support     134
PART II: SERVICES
CHAPTER 7: Service-Orientation Principles with Java Web-Based Services     139
7.1 Service Reusability     140
Agnostic Functional Contexts     140
Highly Generic Service Logic     141
Generic and Extensible Service Contracts     144
Concurrent Access to Service Logic     145
7.2 Standardized Service Contract     151
Top-Down vs. Bottom-Up     151
Mapping Between Java and WSDL     152
Wrapped Document/Literal Contracts     153
Implicit and Explicit Headers     154
Explicit Headers     154
Implicit Headers     157
No Headers     159
Data Mapping with REST     159
Conversion Between JSON and POJOs     161
Binary Data in Web Services     165
Binary Data in REST Services     170
Use of Industry Standards     175
7.3 Service Loose Coupling     176
Separation of Contract and Implementation     177
Independent Functional Contexts     179
Service Consumer Coupling     180
7.4 Service Abstraction     184
Abstracting Technology Details     185
Hiding Service Details     185
Document Constraints     188
7.5 Service Composability     189
Runtime Environment Efficiency     190
Service Contract Flexibility     192
Standards-Based Runtime     193
7.6 Service Autonomy     194
Well-Defined Functional Boundary     194
Runtime Environment Control     195
High Concurrency     196
7.7 Service Statelessness     197
Orchestration Infrastructure     198
Session State     198
Storing State     199
7.8 Service Discoverability     204
Design-Time Discoverability     204
Runtime Discoverability     205
Service Registries     208
CHAPTER 8: Utility Services with Java     211
8.1 Inside the Java Utility Service     212
Architectural Considerations     212
Utility Service Taxonomy     220
8.2 Utility Service Design and Implementation     221
Utility Service Design     221
Utility Services and Java Editions     226
Utility Services in Java SE     226
Utility Services in Java EE     227
Utility Services and Open-Source Frameworks     229
Spring Framework     229
Transaction Management     229
Data Access Objects     230
Object-Relational Mapping     230
JMS     230
JMX     230
JCA     231
Spring MVC      231
Hibernate     231
Commons Logging and Log4J     231
Utility Services as Web-Based Services     231
Sending XML Data as a String     232
Utilizing      233
Provider-Style Web Service Logic in JAX-WS     234
Building REST Utility Services     236
Testing Considerations     238
Packaging Considerations     239
8.3 Utility Service Types     240
Omni Utility Services     240
Design Considerations     241
Service Implementation     241
Service Consumption     241
Resource Utility Services     248
Persistence/Data Access Resources     248
Messaging Resources     248
Transaction Resources     249
Design Considerations     249
Service Implementation     251
Service Consumption     251
Micro-Utility Services     253
Design Considerations     253
Service Implementation     253
Service Consumption     254
Wrapper Utility Services     257
Design Considerations     258
Service Implementation     259
Service Consumption     259
CHAPTER 9: Entity Services with Java     261
9.1 Inside the Java Entity Service     262
Architectural Considerations     263
Domain Entities vs. Message Entities     265
Data Aggregation     266
Data Access Modes     267
Change Notifications     268
9.2 Java Entity Service Design and Implementation     270
Entity Service Design     270
Designing Domain Entities and Message Entities     271
Designing Stateless Entity Services     272
Designing Business-Relevant Entity Services     273
Designing Generic Entity Services     273
Designing Aggregating Entity Services     275
Entity Service Implementation     278
Java Editions     278
Entity Services as Web-Based Services     282
Entity Web Services Using SOAP     283
REST Entity Services     291
Read-Only and Read-Write Resources     292
Resource Granularity     292
Resource Creation and Location     292
Request Message     292
Response Message     293
Resource Relationships     294
Request Message     294
Response Message     294
Request Message     295
Resource Collections     295
Request Message     295
Response Message     295
Aggregate Entities     297
Request Message     298
Response Message     298
Open-Source Frameworks     302
Testing Considerations     302
Java Packaging Considerations     303
PART III: SERVICE COMPOSITION AND INFRASTRUCTURE
CHAPTER 10: Task Services with Java     307
10.1 Inside a Task Service     308
Performance Considerations     315
10.2 Building Task Services     316
Implementation Considerations     316
Web-Based Task Services     320
Task Services with SOAP and WSDL     320
Task Services with REST     324
Testing Considerations     332
Packaging Considerations     334
CHAPTER 11: Service Composition with Java     335
11.1 Inside Service Compositions     336
Service Composition Roles     336
Compositions and MEPs     337
Synchronous and Asynchronous Invocation     338
Service Level Agreements (SLAs)      339
11.2 Java Service Composition Design and Implementation     340
Composition Logic: Coding vs. Orchestration     340
REST Service Composition Considerations     341
Composition Member Endpoints     344
Error Handling     345
Schema Type Reuse     353
Web-Based Services vs. Java Components     359
Packaging, Testing and Deploying Composed Services     362
11.3 Service and Service Composition Performance Guidelines     368
Measuring Performance     368
Testing Performance     370
Caching     371
Data Grids     371
REST Caching     372
Scaling Out Services with State     374
Handling Failures     375
Parsing and Marshaling     376
CHAPTER 12: ESB as SOA Infrastructure     379
12.1 Basic Traditional Messaging Frameworks     380
RPC vs. Messaging     381
Technology Coupling     82
Spatial Coupling     382
Temporal Coupling     382
Message Producers and Message Consumers     385
12.2 Basic Service Messaging Frameworks     389
Basic Service Message Processing without ESBs     389
Message Routing without an ESB     390
Message Transformation without an ESB     391
Basic Service Message Processing with ESBs     392
Message Routing with an ESB     392
Message Transformation with an ESB     392
12.3 Common ESB Features Relevant to SOA     397
Service Lookup and Invocation     397
Service Processing     399
Service Composition Support      401
REST API Management Support     402
PART IV: APPENDICES
APPENDIX A: Case Study Conclusion     405
A.1 NovoBank     406
A.2 SmartCredit Co.     407
APPENDIX B: Service-Orientation Principles Reference     409
APPENDIX C: SOA Design Patterns Reference     425
APPENDIX D: The Annotated SOA Manifesto     519
About the Authors     533
About the Foreword Contributor     535
About the Contributors     537
Index     539