Because Java could be distributed in platform-independent bytecode, it promised to make applications portable across client and server operating systems and hardware. In theory, code written for one machine could run on any other machine. And by positioning Java not merely as a programming language but as a platform, Sun set out to weaken the OS hegemony exercised by Microsoft.

Sun's timing was propitious. Desktop complexity drove a return to centralized administration, while the Internet spurred interest in high-performance Unix servers. Meanwhile, businesses with sophisticated mainframe applications bucked these trends, reluctant to relinquish their proven workhorses for less-reliable client/ server architectures. By suiting all these scenarios, Java's "write once, run anywhere" mantra built the heat and hyperbole surrounding this new language.

But it was inevitable that Java's caffeine high would eventually lead to a cold, icy comedown. The promise of "write once, run anywhere" has too often turned into "write once, test and debug everywhere." The vow to extend Java via the browser without touching the client is seen as sales hype. There are even some poised to toss plastic roses on the grave of client-based Java.

But if Java didn't deliver the ultimate network high in its first three years of existence, that's not to say it isn't a brilliant success overall. Java is many things, and some of these things make the enterprise grade, while others fall behind. For example, Java is positioned as:

· a development language that can cut development cycles for very sophisticated applications by a factor of two, while building in greater reliability than alternatives such as C++. It's also a language that can't yet be ubiquitous because of performance and compatibility issues (see "Does Java Need More Caffeine?" page 72);

· a way to write portable client/server code that is widely perceived as far from perfect but much better than any alternative;

·an important language for third-party enterprise application development, though Java draws extremely low marks from businesses seeking out such applications today (see "How Businesses Grade Sun's Java," on page 64);

·a server platform that is gaining incredible momentum both as a way to knit together back-end applications and to create simpler and more functional user interfaces, but which still lacks a critical reference model;

·a distributed computing platform, along with CORBA (Common Object Request Broker Architecture), that must compete with Microsoft's COM (Component Object Model) framework and growing IS dependence on combination frameworks, including those that tap CORBA/COM with singular and proprietary APIs and platforms (see "Muddied Waters: Distributed APIs," below);

·a new product approach built around the still far-flung and nebulous features to be found in emerging application servers;

·an emerging client platform for niche vertical applications and embedded systems that figures to catch on, given Java's ease of development and reliability (see "JavaOS: Think Thin," page 78);