SAS® AppDev Studio 3.0 Developer's Site

Java Technologies for Clients

Java-based solutions have become increasingly popular due to their portability, flexibility, and performance. You can use SAS AppDev Studio to develop both Java applets and Java applications. Tools such as webAF software and webEIS software enable you to create applets and applications that access your SAS data.

If you need to create highly interactive user interfaces, consider using client-side Java. Both applets and applications provide the same level of user interactivity, but they differ in how they are deployed to users.

When you use Java applets, you avoid having to install an application locally on a user's machine. Instead, when an applet is executed (usually by being called from within an HTML page), the necessary Java class files are automatically downloaded from the Web server. The applet is then loaded into memory, typically via a plug-in to the browser that interprets and executes the classes that were downloaded. Because of this deployment model, applets are subject to security restrictions on the client, the server, or both. Make sure that you understand any limitations that your production Web environment may impose.

Java applications can be built and run independently, similar to other executable programs that you might run. These applications must be installed locally on each client machine. For this reason, Java applications have none of the security restrictions that browsers have.

The downside to Java applications is that they still require administration; when the application is updated, those updates must be made on every machine on which the application resides. In contrast, applets provide a scenario that is closer to "zero administration." Updates to an applet need to be made only once - to the image that is stored on the Web server, which is then automatically downloaded to the client the next time that the applet is executed by that client user.