Yakov Fain reaches Lesson 11 in his popular 'Java basics' series. This time he deals with how and why Java programmers working on large projects that have lots of classes usually organize them in different packages; and explores the new element introduced in Java 5.0 called static imports.

Evolving J2EE specifications continue to provide developers and architects with added performance muscle and flexibility for building and optimizing enterprise applications. J2EE advances are both a boon and a challenge as they can provide additional capabilities while also requiring refined development skills. J2EE applications incorporate complex distributed logic and, hence, demand careful, intelligent, and innovative design and implementation techniques.

Most Web applications are typically based on the presentation of information, meaning that functional operations pertaining to retrieving, assembling, and presenting information in the form of content and data largely outnumber functional operations that actually modify the information.

Business services provider Winholesale chose Bowstreet Portlet Factory, and IBM WebSphere Portal, to provide portlet development providing role-based access to the company's financial information.

Will they, won't they? Yesterday, Sun's own Java technology evangelist was being reported as having said they would; now Java co-creator James Gosling - and almost everyone else in Santa Clara who came in contact with the media - says Sun won't be open-sourcing Java. Not yet anyway - though it's under fierce and continuing debate within the company.

Hard on the heels of the announcement by Sun's president and COO Jonathan Schwartz earlier this week that Solaris will be open-sourced comes confirmation from Sun's Java technology evangelist: 'We haven't worked out how to open-source Java - but at some point it will happen,' says popular speaker and expert in Java technology and distributed systems, Raghavan 'Rags' Srinivas.

What are the most important best practices for J2EE, when you include Web services development as a part of J2EE? Three IBM staffers recently had a shot at coming up with a Top Twelve.

One of the exciting new features of the WebSphere Application Server (WAS) 5.0 release is support for J2EE 1.3. With this release of the J2EE specification comes EJB 2.0, which contains a number of features that effectively make both session and entity beans far more flexible and scalable components of an application's architecture.

One of the major innovations in the EJB 2.0 specification, the Message-Driven Bean (MDB), is not supported by WebSphere Application Server 4.0. There are several ways to circumvent this shortcoming - you can wait for WAS 5.0, use another application server, or concoct some sort of pseudo MDB. Since the first two are rarely feasible, I'll describe the last.

An event is an asynchronous notification from an external source, such as a thread or another application. Commands from a user, a timer signaling completion of a specified time period, and the arrival of a message in a queue are examples of events. Two components that are generally involved in event-based processing are the event producer and the event consumer.

It's one of the greatest challenges in enterprise application development: object/relational mapping. Business information lives in relational databases, and applications are made up of objects. There is no shortage of products that attempt a systematic mapping between tables and objects, all with limited success.

EJB application servers speed up software development by eliminating the need to build costly infrastructure. In particular, developers don't need to worry about implementing code that handles concurrency. This does not mean, however, that developers can totally ignore concurrency issues: Configuring an application server for optimal performance requires a thorough understanding of concurrency issues.