Application Architecture for WebSphere: A Practical Approach to Building WebSphere Applications

Architect IBM® WebSphere® Applications for Maximum Performance, Security, Flexibility, Usability, and Value Successful, high-value WebSphere applications begin with effective architecture. Now, one of IBM’s leading WebSphere and WebSphere Portal architects offers a hands-on, best-practice guide to every facet of defining, planning, and implementing WebSphere application architectures. Joey Bernal shows working architects and teams how to define layered architectural standards that can be used across the entire organization, improving application quality without compromising flexibility. Bernal begins by illuminating the role of architecture and the responsibilities of the architect in WebSphere applications and SOA environments. Next, he introduces specific architectural techniques for addressing persistence, application performance, security, functionality, user interaction, and much more. Bernal presents a series of sample architectures drawn from his work with several leading organizations, demonstrating how architectures can evolve to support new layers and changing business requirements. Throughout, his techniques are specific enough to address realistic enterprise challenges, while still sufficiently high-level to be useful in diverse and heterogeneous environments. Coverage includes • Choosing persistence frameworks that serve business requirements without excessive complexity • Avoiding persistence-related problems with performance, security, or application functionality • Designing and deploying effective middle layers and dependent libraries within WebSphere Application Server • Using WebSphere mechanisms and architectural techniques to avoid common security attacks such as SQL injection • Improving performance with WebSphere Application Server caching, including Distributed Maps and Servlet/JSP fragment caching • Using presentation frameworks to provide fast, robust, and attractive user interaction • Incorporating portals that provide a standardized framework for merging multiple applications Joey Bernal is an Executive IT Specialist with IBM Software Services for Lotus. Senior Certified with IBM as an IT Specialist, he has an extensive background in designing and developing Web and Portal Applications. He often leads IBM teams that have assisted dozens of clients in leveraging WebSphere Portal to address architecture, design, and implementation challenges. A frequent speaker on WebSphere and portal topics, Bernal is coauthor of Programming Portlets, and hosts the developerWorks blog: WebSphere Portal in Action. Prior to joining IBM, he was Director of IT for an incentive and performance improvement company, and served as lead technical advisor and architect for high-profile Internet and intranet applications at several Fortune 500 companies. You can also visit the author’s Web site at www.bernal.net. The IBM Press developerWorks® Series is a unique undertaking in which print books and the Web are mutually supportive. The publications in this series are complemented by resources on the developerWorks Web site on ibm.com®. Icons throughout the book alert the reader to these valuable resources.

Table of Contents:
Foreword xix Acknowledgments xxi About the Author xxiii   Preface xxv   Chapter 1 Application Architecture 1     What Is Application Architecture? 1         Architects and Architecture 2         Application Architecture and Engineering 7     WebSphere and IBM 8         IBM WebSphere Application Server 9         A Word about Specifications 13         How Close to the Specification Should I Stay with My Architecture? 13         WebSphere Extensions to Consider 14         One Size Does Not Fit All 15     Building Blocks of Application Architecture 16         Detail in Layering 18         A Complete Example 18         Layers Versus Tiers 22         Deployment Patterns for a Layered Architecture 24         Layers Versus Modules 27     A View Perspective on Architecture 30     Conclusion 31     References 31   Chapter 2 Setting a Standard 33     Organizational Standards and Conventions 33     Putting the “Engineering” in Software Engineering 34         Standards Documentation 36         Naming Standards and Conventions 36         Packages 37         Classes and Interfaces 37         Functions and Methods 38         Variables and Constants 38         Java Server Pages 38         Internal Documentation 39         Class Header Information 40         Class Methods 41         Getters and Setters 41         Inline Comments 41         Logging and Tracing 42         System.out 43         Using the Logger 43         Logging Levels 45         Method-Level Timers 47     Working with Logging and Tracing 49         Too Much Logging? 50         Why Not Use Aspects? 51         Exception and Error Handling 51     Project and Packaging File Structure 53         Using External Libraries 54     Unit Testing Requirements 55         What Is a Unit? 58         The Trouble with Web Testing 58         Agile Approaches 59     Code Completion and Review Process Requirements 59         Code Reviews 60         You Don’t Have to Know Java for a Code Review 62     Communicating the Vision the Wiki Way 62     Conclusion 63     Reference 64   Chapter 3 Persistence Matters 65     Types of Persistence Frameworks 65         Object/Relational Mapping 66         SQL-Based Frameworks 66         Why Not Roll Your Own Framework? 66     WebSphere Data Source Resource Reference 67     iBATIS Framework 68         Implementing the Customer Class and Customer SQL Mapping 72         Configurating iBATIS 74         Adding the Spring DAO Framework 76         Running a Test 80         Transactional Thinking 82     EJB 3 and the Java Persistence API 83         Understanding the Approach 84         Entities with POJOs and Annotations 84         Entity Managers 88         Testing the Application 93         Remote Clients 94     Conclusion 97   Chapter 4 Designing the Middle Tiers 99     Business Logic 99     Another HelloWorld Example 101         Making the Business Layer Accessible 103         Getting Ready for Unit Testing 105     WebSphere Shared Libraries 107         Making the Library Visible 110         Mapping Shared Libraries to Class Loaders 114         Testing the Business Layer 116         Controlling Shared Libraries 117         Implementation Options 120         Business Process Layers 122     Conclusion 123     References 123   Chapter 5 Presentation Frameworks 125     Choosing a Presentation Framework 125     JavaServer Faces 127         Lifecycle Phase Listener 130         About the Sample Application 131         Masking and Conversion Errors 144         JSF as a Standard 146     IBM’s JWL 146     Conclusion 147     References 148   Chapter 6 Investing in a Portal 149     Incorporating a Portal into Your Architecture 150         Virtual Portal Technology 151         Business-to-Employee (B2E) Portals 152         Business Process or Forms-Based Portal 152     Portals Versus the Web App 153         Role-based Navigation and Content Delivery 153         Security and Single Sign-on 153         Content Personalization 154         Portlet Aggregation and Composite Applications 154     Applications as Portlets 154     The Java Portlet API 156         Java Portlet API 2.0 158         Portlet Preferences 160     A Simple Portlet Example 161         Switching Modes Programmatically 168     Conclusion 172     References 173   Chapter 7 SOA and Web Services 175     Pinning Down SOA 175     How to Implement SOA 177         Service Modeling 177         Services as Business Functions 177         Managing Service Data Elements 178         A Commitment from the Business 178     Things to Consider about Web Services 179         Performance 179         Standardization 180         Manageability 180         Web Services Feature Pack for WAS 181     Credit Limit Service 182         Testing the Service 184         Building a New Client Application 187         Simple REST-Based Services 189     Conclusion 194     References 195   Chapter 8 Caching and Performance 197     Designing for Performance 197         Architecture Concerns 198         Performance Terminology 199         Caching Considerations 199         Caching Design Options 200         Sizing a Cache 201         When Not to Cache 202         User Session Caching 202     Caching in WebSphere Application Server 203         IBM HTTP Server and the Caching Plug-in 205     Using the Distributed Map 206         Creating a New Distributed Map 206         Testing the Distributed Map 209     HTML Fragment Caching 214         Monitoring the Fragment Cache 216         ESI Plug-in Caching 217     Conclusion 218     References 218   Chapter 9 Keeping Things Secure 219     Why Security Is Important 219         The Role of the Security Architect 221         SQL Injection Example 222         Protecting against SQL Injection Attacks 224     WebSphere Security Basics 225         Authenticating Application Users 225         Adding a Filter to the Login Process 236     Architecting for Security 237         WebSphere Single Sign-on 238         WebSphere Authorization 239     Conclusion 241       Chapter 10 Managing Your Applications 243     Managing Applications 243         Enforcing Architecture Adherence 244         Standing by Your Decisions 245         Documenting Libraries 245         Managing Organizational Process 246         Avoiding Common Process Malpractices 249         Enforcing Adherence and Reuse with Technology Solutions 251         Using a Registry and Repository 251     Project Methodology 253         Common Methodology Problems 254         Change Control Board 255     Conclusion 256     References 257   Appendix A Setting up the Data Sample 259     Getting Started 259         Database and Schema 260     Setting Up Your Data Environment 261         Creating the DB2 Database 262         Load the Classic Models Data 264         Creating a WebSphere Data Source 266     Conclusion 275   Appendix B Running the Examples 277     Chapter Code Samples 277         Chapter 2 278         Chapter 3 278         Chapter 4 278         Chapter 5 278         Chapter 6 279         Chapter 7 279         Chapter 8 279         Chapter 9 280     Conclusion 280   Index 283