InformationWeek

f you haven't heard about Java Web Start, you're not alone. The product, unveiled in June, was lost in the din of news coming from the JavaOne conference. However, Java Web Start may prove to be one of Sun Microsystems' most important moves.

Java Web Start is a server-based Java application deployment technology that lets Java applications be sent to client computers via a Web site. (It's available for download from Sun.)

When the site visitor clicks on a link, the Java application is downloaded to the client computer and installed. If any Java Software Development Kit elements are missing, such as the proper Runtime or Virtual Machine, those components are also downloaded and installed.

Once the application is installed, it can be run locally again without downloading it, as was the case with browser-based Java applets. When the app runs, it checks the server for updates to the application code or the Java environment. Any changes or updates are downloaded and installed before the application begins.

What does this mean for businesses? It eliminates the headaches that have driven IT departments crazy as they tried to manage hundreds or thousands of clients. The application and runtime environment are always kept up to date, and manual installs at every client are no longer required.

Java Web Start will even let multiple applications use different runtimes. For example, one app can use Java Runtime version 1.2 while a second one can use version 1.3. Both applications can run simultaneously, each in its own memory space. Java Web Start uses the entire Java security model, such as the security sandbox or digital signatures for varying degrees of security.

"From ground zero, the whole Java platform has been designed with the Web and the network in mind, so the idea of network-based applications has been part of the mission," says Blake Connell, group product marketing manager for Java at Sun. Java Web Start "helps fulfill the larger Java mission of Web-based deployment. It's perfect for deploying to Windows, Linux, and Solaris desktops. It fulfills the mission of cross-platform deployment."

Per-Se Technologies Inc., a developer of medical-software systems in Atlanta, held off on a Java application until Sun delivered Java Web Start. "This is the age-old problem. We didn't want to ask our clients to wander to hundreds of PCs to install our client," says Randal Clegg, director of platform development at Per-Se. Java Web Start "was virtually identical to something we had dreamed up and said [to Sun] this is what we want."

Sun hopes to add Java Web Start into Java 2 Enterprise Edition for client-application delivery, but that's a few versions away, according to Sun.