Recently, I was listening to the The Java Posse, part of which is a segment called Java Application of The Week (or somesuch). One of the recent apps was a product called JavaRebel. According to their website, the product "enables you to see changes to your code immediately, without the need to redeploy an application or perform a container restart". It goes far beyond HotSwap or hot redeploy in that it allows immediate loading of just about any kind of change (including various framework configurations) with the exception of inheritence hierarchy or interface changes. I decided to get the trial version and give it a go myself on a project I am currently working on which uses Oracle's OC4J container, which, at least in our current situation, does not allow you to hotswap anything with the exception of front-end pages. After getting everything configured, the thing works like a charm. They suggest having your IDE build to wherever you have exploded your WAR under your app server. Unfortunately, Eclipse does not allow you to specify a build location outside the project, so I fooled it by essentially creating a hard link to where the exploded WAR lives under the app server. I'm running on Windows and there's no out-of-the-box way to create a hard link as there is in Unix/Linux, so I used Mark Russinovich's Junction utility which does so, for all intents and purposes.