Performance Tuning for Content Manager

Chapter 2. Content Manager base products 55

respond to an ever-changing marketplace without the costs of migrating to a

different technology base.

In the following sections, we provide a

general overview of J2EE, WebSphere

Application Server architecture, and architectural components. The material

provided are an extraction from the existing WebSphere publications. For more

detailed information, refer to:

 IBM WebSphere Application Server, Version 5.1 Information Center

http://publib.boulder.ibm.com/infocenter/wasinfo/v5r1/index.jsp

 IBM WebSphere Application Server, Version 5.1: Getting started, SC31-6323

http://www.ibm.com/support/docview.wss?uid=pub1sc31632301

 WebSphere Application Server Information Center:

http://www.ibm.com/software/webservers/appserv/was/library

2.2.1 J2EE overview

Java 2 Platform, Enterprise Edition (J2EE) is the standard for developing,

deploying, and running enterprise applications. WebSphere Application Server

supports all of the J2EE APIs.

The J2EE standard applies to all aspects of designing, developing, and deploying

multi-tier, server-based applications. The J2EE standard architecture consists of:

 Standard application model for developing multi-tier applications

 Standard platform for hosting applications

 Compatibility test suite for verifying that J2EE platform products comply with

the J2EE platform standard

 Reference implementation providing an operational definition of the J2EE

platform

The J2EE platform specification describes the runtime environment for a J2EE

application. This environment includes application components, containers, and

Resource Manager drivers. The elements of this environment communicate with

a set of standard services that are also specified.

J2EE platform roles

The J2EE platform also defines a number of distinct roles performed during the

application development and deployment life cycle:

 Product provider designs and makes available for purchase the J2EE

platform, APIs, and other features defined in the J2EE specification.

56 Performance Tuning for Content Manager

 Tool provider provides tools used for the development and packaging of

application components.

 Application component provider creates Web components, enterprise beans,

applets, or application clients for use in J2EE applications.

 Application assembler takes a set of components developed by component

providers and assembles them in the form of an enterprise archive (EAR) file.

 Deployer is responsible for deploying an enterprise application into a specific

operational environment.

 System administrator is responsible for the operational environment in which

the application runs.

Product providers and tool providers have a product focus. Application

component providers and application assemblers focus on the application.

Deployers and system administrators focus on the runtime.

These roles help identify the tasks to be performed and the parties involved.

Understanding this separation of roles is important for explaining the approach

that should be taken when developing and deploying J2EE applications.

J2EE benefits

The J2EE standard empowers customers. Customers can compare J2EE

offerings from vendors and know that they are comparing parallel products.

Comprehensive, independent compatibility test suites ensure vendor compliance

with J2EE standards.

Some benefits of deploying to a J2EE-compliant architecture are:

 A simplified architecture based on standard components, services, and

clients, that takes advantage of write-once, run-anywhere Java technology.

 Services providing integration with existing systems, including Java Database

Connectivity (JDBC); Java Message Service (JMS); Java Interface Definition

Language (Java IDL); JavaMail™; and Java Transaction API (JTA and JTS)

for reliable business transactions.

 Scalability to meet demand, by distributing containers across multiple

systems and using database

connection pooling, for example.

 A better choice of application development tools, and components from

vendors providing off-the-shelf solutions.

 A flexible security model that provides single sign-on support, integration with

legacy security systems, and a unified approach to securing application

components.