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Sun's plans for EJB's future are similar in one sense to Microsoft's plans for DCOM and COM+: They are evolutionary, not revolutionary. Every vendor wants its technology to be viewed as stable, and Sun is no exception. EJB 1.1 is expected at the JavaOne conference in June, but will probably be a tightened spec with some extensions, not a major rewrite. Sun wants to add XML (Extensible Markup Language) to the way EJB is built to help any server understand EJB. It also plans to enhance connectivity to legacy systems, such as IBM's CICS and IMS, without losing portability. Finally, Sun is developing a long-overdue reference implementation of EJB. The beta version of the reference implementation is slated for next quarter, with the final version due in the fourth quarter of this year.

The relationship between EJB and Sun's upcoming Java2 Enterprise Edition has been uncertain, especially whether Java2 would pull resources away from EJB. "Just as the Java Virtual Machine is core to Java2, EJB is core to Java2 Enterprise Edition," says Bill Roth, product line manager at Sun for the Java2 Enterprise Edition platform.

The Java2 Enterprise Edition will include and require many of the other core Java technologies: JNDI (Java Naming and Directory Interface), JDBC (Java Database Connectivity), servelets and Java Server Pages. In addition, CORBA/IIOP is a required part of Java2 (which includes a reference implementation CORBA 2.3-compliant ORB, Java IDL) and forms much of the transport infrastructure for Java2 Enterprise.

"The CORBA technologies represent the plumbing for us, and the real hope for interproduct interoperability," Roth says. Sun's stated goal is to make the underlying CORBA "plumbing" invisible to the Java2 programmer. In fact, while Sun says it is still paying attention to DCOM interoperability via a bridging strategy, Java2 Enterprise is not wire-transport neutral; Sun will use CORBA/IIOP as the communications infrastructure. Interoperability and interobject communication will be through RMI over IIOP, making CORBA essential, but invisible. Sun is planning to take a more public role in the OMG, a further indication of a gradual merging of elements of CORBA and EJB over the coming year.

Because EJB is fundamentally built on the Java language, some of the issues particular to Java have a direct impact on EJB. Primary among these is performance, long Java's Achilles' heel. Sun has released a beta version of the HotSpot compiler, and promises a final version with greatly improved performance. In the meantime, IBM's new version of Visual Age for Java produces native binaries, but that's a short-term solution that contradicts Java's "write once, run anywhere" model. Some heavy-duty, 100 percent Java-written production applications are starting to appear, so clearly the performance problems can be addressed with enough care, and Java has proved itself to have perfectly acceptable performance on the server side for most uses. Also, Sun plans to introduce a new revision to servelets soon, with improved architecture and performance features. Finally, Java's future direction will come into question if Microsoft loses its ongoing court battle with Sun and cuts off its support for Java. That action, while not necessarily fatal, would put a speed bump on the road to Java's, and thus EJB's, widespread acceptance in the enterprise space. On the other hand, it would also provide a rich market for enhancements, such as Sun's Java Plug-In, which allows enterprise developers to configure either Microsoft Internet Explorer or Netscape browsers to use a specific version of Sun's Java Runtime Environment (JRE) instead of the one included with the browser.

Sun is trying to position EJB as "the industry's best hope to deliver true interoperability," Roth says. But the OMG has shown what a difficult challenge such a goal can be. Sun also suggests that EJB can be a simplifying layer on top of CORBA and DCOM. For EJB to succeed, however, it needs to accelerate the availability of third-party development tools, and avoid the pitfalls of specification ambiguity that plagued CORBA, while at the same time not be so dictatorial as to discourage vendors. Sun says it doesn't see EJB as a direct competitor to Microsoft and this is true: EJB by itself is just a piece of paper; it's the supporting products the vendors develop using EJB that will provide competition for Microsoft and DCOM/COM+ based products.

Send your comments on this article to Richard Hoffman atrhoffman@nwc.com.