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What is Consumer JRE, Java Kernel

The JRE 1.6 update 10 around the corner. Sun's Initiative to slim down a huge 14 MB JRE download is very much understandable to keep itself in competition. But for an average joe, How would this matter? There is some confusion in understanding what is this release about. Why is this in minor release update? What is expected? Why now?

Java Kernel, has been in talks for a while now. Why now - because with AIR, SilverLight taking on RIA market, Java cannot lag behind sticking to its thick client apis (AWT,SWT). But here is the thing, This release hass no change in API. Its just a new JRE implementation.

Okay What is it? The JRE consists of a bootstrap library and a bunch of system, language and util libraries. There may be inter dependencies in these libraries. Making the smallest possible JRE that can start on itself is the Java Kernel. After You get java kernel, Consider that a java program is asking for some dependencies, The Java Kernel *downloads* it and loads in the program for you. So its *gradually* getting the complete JRE over time. This way, A system that doesn't have JRE at all, can start loading an application/applet with a bare minimum start up time.

Does it effect you? Yes and No. Technically, you wont even bother about this change. as it is an implementation difference. but performance and deployment wise, it would give you more bang for the buck in User experience. Like say an applet can be made a web start program just like that. and to run a small web start program you need not have the customer load a huge VM.

What is Expected? If you are familiar with OSGi philosophy, you can compare this modularisation with that philosophy. Right now, Sun's move is only the first step. Moving forward, this modularisation will only benefit The experience. Having said that, One can attribute this move only to the lazy-ness of Sun, waiting on others to innovate and Sun playing only the catch up. However, its good for java community.

If you are keen on reading more technical details. Read here.

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