Java SE 6, Update 21 Available
Oracle released update 21 to Java SE 6 today. This update mainly includes support for more operating systems, and bug fixes. New OS and environment support includes:
-Oracle Enterprise Linux, versions 4.8, 5.4, and 5.5 -Red Hat Enterprise Linux, versions 5.4 and 5.5 -Oracle's Virtual Machine environment (Oracle VM), v188.8.131.52.0 -Google Chrome, v4.0
As for features, the one notable item is the addition of an optional progress indicator that can be displayed and updated when a Java application launches. For more on this, check out the tutorial, Customizing the Loading Experience.
Additionally, this update includes the latest version of VisualVM, which is an excellent tool to help analyze what's happening inside a running Java virtual machine, and the application it's hosting. You can view threads and their activity, observe heap usage and garbage collection activity, profile your application, and more, and all in real-time as your application executes. If you're not using Visual VM (and Visual GC), you should be. You can find more information about it here.
Finally, the release contains a lot of bug fixes, mostly in the areas of the HotSpot compiler and the G1 soft-real-time garbage collector. There are many others, so you may want to check the Bug Fix List to see if any apply to you, or may help with any JVM issues you've been experiencing.
The download for the update can be found here.
Happy coding! -EJB