Java 2 Enterprise Edition

CTO Forum

January 19, 2001

Agenda

• Flavors of Java

• Overview of J2EE

• Advantages of J2EE

• Key considerations

• Parting thoughts

Flavors of Java

• Java 2 Micro Edition (J2ME)– Java on devices

• Java 2 Standard Edition (J2SE)– Core API, compiler, runtime

environment

• Java 2 Enterprise Edition (J2EE)– Enterprise-class service specifications

Overview of J2EE

• Family of enterprise-class service specifications– APIs

• Reference implementation– Working server and application

• Compatibility test suite– 6,000 tests– Two certified application servers

• BEA WebLogic 5.1 and iPlanet App Server 6.0

• Blueprints– Architectural best practices

J2EE specifications

• Enterprise JavaBeans– Business components and logic

• Customer, order, OrderProcessor

– Session beans• Stateful and stateless

– Entity beans• Container-managed persistence• Bean-managed persistence

• Servlets– Java code with embedded presentation logic

• JavaServer Pages (JSP)– Presentation logic with embedded Java code

J2EE specifications

• Java Transaction API (JTA)– API for controlling transactions

• Java Transaction Service (JTS)– Service that controls transactions

• Java Naming and Directory Interface (JNDI)– API to “lookup” services

• Java Database Connectivity (JDBC)– Access to RDBMS

J2EE Specifications

• JavaMail– E-mail

• RMI over IIOP (CORBA compliance)– CORBA/Java interoperability

• XML support• Java Message Service (JMS)– Synchronous and asynchronous– Point-to-point/queue-based and

public/subscribe

Advantages of J2EE

• ‘Bilities– Reusability, manageability, extensibility,

scalability, stability, flexibility

• Full complement of application services• More robust applications– No need to build plumbing

• Faster time to market• Architectural flexibility

Advantages of J2EE

• Fairly mature technology– Several years old for most specs– Multiple releases of app servers

• Platform independence– No vendor lock-in – sort of…– Investment protection

• Wealth of technologies and products• Competitive environment• Relatively easy to find talent

Key considerations

• J2EE is not a true standard– Owned by the Java Community Process (JCP)

• J2EE evolves quickly– Difficult to keep developers up-to-date– Potential quality issues with products

• Complicated set of services– Lots of moving parts– Requires architecture talent and experience

• Hard to find “one throat to choke”

Parting thoughts

• J2EE is the way to build enterprise-class applications

• Systems development principles still apply

• Find people who have “been there, done that”

Questions?

Info@idea.com