Definitive, Comprehensive SCEA Exam Prep-Straight from Sun's Exam Developers!

This book delivers complete, focused review for Sun's new Sun Certified Enterprise Architect (SCEA) for Java EE certification exam-straight from two of the exam's creators! SCEA lead developer/assessor Mark Cade and SCEA lead developer/assessor Humphrey Sheil offer powerful insights, real-world architectural case studies, and challenging sample questions that systematically prepare you for the actual exam. For every question, the authors show why the right answers are right-and why the other answers are wrong. Cade and Sheil cover every SCEA exam topic, skill, and technique, including:

• Understanding system architecture and its goals
• Decomposing larger systems into components organized by tiers or layers
• Addressing requirements for scalability, maintainability, reliability, availability, extensibility, performance, and security
• Building effective web (presentation) tiers, and analyzing tradeoffs associated with using web frameworks
• Leveraging EJB 3's enhancements for business tier development
• Covering new enhancements in the JEE 5 platform
• Choosing and architecting the best integration and messaging components for your system
• Using the Java security model to enforce confidentiality, integrity, authorization, authentication, and non-repudiation
• Using the most powerful and useful Java EE architecture patterns
• Documenting Java EE architectures through visual models and narratives

The authors also present detailed guidance for handling every element of the SCEA exam-including your development and defense of a complete real-world architectural solution.

Mark Cade is a lead developer and assessor of the SCEA exam covered in this book. He worked at the Sun Microsystems Java Center as a Senior Java Architect, where he has extensive experience creating architectures for Java EE solutions for Fortune 500 companies. He has more than 20 years of experience as a software engineer.

Humphrey Sheil is a lead developer and assessor for the SCEA exam covered in this book. With a background specializing in enterprise architecture and integration in the United States and Europe, he holds a M.Sc. and B.Sc. in Computer Science from University College Dublin. He is currently the CTO at Comtec Group.

Acknowledgments . . . xv

About the Authors . . . xvii

Chapter 1 What Is Architecture? . . . 1

Introduction . . . 1

Prerequisite Review . . . 1

Discussion . . . 2

Understanding Architecture . . . 2

Role of the Architect . . . 5

More Detail on the Exam Itself . . . 6

Part I: Multiple Choice . . . 7

Part II: Solving the Business Problem . . . 8

Part III: Defending Your Solution . . . 9

Preparing for the Exam . . . 10

Preparing for Part I . . . 10

Preparing for Part II . . . 11

Preparing for Part III . . . 11

Essential Points . . . 11

Review Your Progress . . . 11

Chapter 2 Architecture Decomposition . . . 13

Introduction . . . 13

Prerequisite Review . . . 14

Discussion . . . 14

Decomposition Strategies . . . 14

Layering . . . 15

Distribution . . . 15

Exposure . . . 16

Functionality . . . 16

Generality . . . 16

Coupling and Cohesion . . . 16

Volatility . . . 16

Configuration . . . 16

Planning and Tracking . . . 17

Work Assignment . . . 17

Tiers . . . 17

Client . . . 17

Web . . . 18

Business . . . 18

Integration . . . 18

Resource . . . 18

Layers . . .18

Application . . . 19

Virtual Platform (Component APIs) . . . 19

Application Infrastructure (Containers) . . . 19

Enterprise Services (OS and Virtualization) . . . 19

Compute and Storage . . . 19

Networking Infrastructure . . . 20

Service-Level Requirements . . . 20

Performance . . . 20

Scalability . . . 20

Reliability . . . 21

Availability . . . 21

Extensibility . . . 22

Maintainability . . . 22

Manageability . . . 22

Security . . . 22

Impact of Dimensions on Service-Level Requirements . . . 23

Capacity . . . 23

Redundancy . . . 23

Modularity . . . 23

Tolerance . . . 24

Workload . . . 24

Heterogeneity . . . 24

Common Practices for Improving Service-Level Requirements . . . 24

Introducing Redundancy to the System Architecture . . . 24

Improving Performance . . . 27

Improving Availability . . . 28

Improving Extensibility . . . 29

Improving Scalability . . . 30

Tiers in Architecture . . . 30

Two-Tier Systems . . . 31

Advantages . . . 31

Disadvantages . . . 31

Three- and Multi-Tier Systems . . . 31

Advantages . . . 32

Disadvantages . . . 32

Essential Points . . . 32

Review Your Progress . . . 33

Chapter 3 Web Tier Technologies . . . 35

Introduction . . . 35

Prerequisite Review . . . 36

Model View Controller (MVC) . . . 36

Web Container . . . 36

Servlets . . . 37

Filters . . . 38

Listeners . . . 39

JavaServer Pages (JSP) . . . 39

Java Standard Tag Library (JSTL) . . . 40

Unified Expression Language (EL) . . . 40

Managing Sessions . . . 40

JavaServer Faces (JSF) . . . 41

Templating Frameworks . . . 41

Web Frameworks . . . 42

Discussion . . . 42

JSPs and Servlets-Standard Uses . . . 42

JSF-Standard Uses . . . 43

Web-Centric Implementations . . . 43

EJB-Centric Implementations . . . 44

Rationale for Choosing Between EJB-Centric and Web-Centric Implementations . . . 45

The Future of Client-Server Communication . . . 46

Essential Points . . . 46

Review Your Progress . . . 47

Chapter 4 Business Tier Technologies . . . 51

Introduction . . . 51

Prerequisite Review . . . 52

Enterprise Java Bean . . . 53

Session Bean . . . 54

Stateless Session Bean . . . 54

Stateful Session Bean . . . 55

Entity Beans . . . 56

CMP Entity Bean . . . 56

BMP Entity Bean . . . 57

Entity Class . . . 57

Persistence Strategies . . . 58

Message-Driven Bean . . . 58

Discussion . . . 59

EJB Advantages and Disadvantages . . . 59

Scalability . . . 59

Security . . . 60

Contrasting Persistence Strategies . . . 60

Ease of Development . . . 60

Performance . . . 60

Extensibility . . . 61

EJB and Web Services . . . 61

EJBs as Web Service End Points . . . 61

EJBs Consuming Web Services . . . 61

Advantages and Disadvantages . . . 62

EJB 3 . . . 62

Ease of Development . . . 63

Container in EJB 3 . . . 63

JPA in EJB 3 . . . 63

Essential Points . . . 64

Review Your Progress . . . 65

Chapter 5 Integration and Messaging . . . 69

Introduction . . . 69

Prerequisite Review . . . 70

Web Services . . . 71

SOAP . . . 71

WSDL . . . 72

JAX-RPC . . . 72

JAX-WS . . . 72

JAXB . . . 72

JAXR . . . 73

JMS . . . 73

JCA . . . 74

Discussion . . . 75

Java to Java Integration . . . 75

Java Messaging Service (JMS) . . . 76

Java to Non-Java I…