Over the last couple of days, a beta release of the Java JDK called Java 6 Update N was released. This is the update which includes the Consumer JRE (aka Java Kernel) which attempts to modularize the Java runtime. The kernel allows a user to download only the required portions of the runtime in order to run their application. This should reduce load time as well as reduce the memory footprint of Java applets and Web Start applications. I’m not too sure what the implications are for regular standalone desktop Java apps. The kernel feature is not yet available in this beta and so it is difficult to test or measure any improvements. I did notice that the feature is referred to as Kernel installation mode which implies that it will only affect the installation of the JRE for users that don’t have it installed.
A feature called Quick Starter is also included in this update. Quick Starter will pre-fetch portions of the JRE into memory in order to improve cold start time of the JRE. There is some mention that this feature is only available for Windows which would be a shame. Hopefully this will be corrected at the beta progresses.
There are other interesting features in this update however including Nimbus which is a new look and feel, improved runtime detection and installation as well as graphics hardware acceleration support.
I did see a blog reference (that has since been removed) that Nimbus and by extension the other features in the beta will be available in Java 6 Update 5. I imagine that based on the results of the beta, that update that will include this feature could change. Sun is also not making any official time lines available related to the inclusion of the improvement into the Java runtime.
More info at:
- Chet Haase Blog – Access Granted
- Jasper Potts Blog – Nimbus Early Access
- java.net forum – Quick Starter : First Impressions