In terms of animation Applets fall short… way short. Writing a program to animate something is as painful as drawing a picture with LOGO. Applets lack the ability to draw and animate as effectively as alternatives like flash and silverlight. Flash gives the user simple easy ways to import media or draw vector (or raster) images and animate them using keyframes. Need advanced animation or programatic animation? Flash actionscript has you covered. It can animate as well as provide an event driven program.

Java Applets however have none of this. Each frame must be drawn programatically and requires a blanking in between. While this isn’t a huge inconvenience it shows Java applets are not intended to be powerful animation tools.

Additionally Java applets are supposed to provide a robust GUI experience. In actuality Java applets provide for a clunky slow loading experience frequently resulting in a large ominous gray box in the center of a browser.

When Java originated (early 90’s) applets were a very powerful tool allowing for robust GUI development. Java applets were leaps and bounds ahead of any early version HTML controls. This utility however diminished as HTML became less of a presentation markup and more of an interaction markup. My realization that java applets are obsolete was concreted by AJAX, asynchronous Javascript and XML. This technology fixed the primary problem still plaguing HTML: The HTTP protocol.

Historically Web pages have always functioned with a query and a response. forms simply alter parameters in the query. What this caused was any time any server interaction occured, the web page needed a total page reload. This greatly diminishes a HTMLs ability for GUIs as any updates required completely reloading the page. AJAX changed this.

AJAX allows for partial page refreshes. That is a portion of the page can be reloaded through javascript and xml calls resulting in faster more robust GUIs being developed using a STANDARD HTTP connection appropriate for in browser use.

Calling them completely obsolete is unfair though. Java applets do have a purpose, just not in browser. Java applets can be a powerful visualization tool of data as well an excellent GUI for showing off a proof of concept. In fact things like Java Web Start have done an excellent job of rejuvenating applets by breaking them out of the browser and executing them in their own window where they belong.