building java part of openjdk

Question

I need to change some of JFC classes and thus wanted to do it with openjdk. I do not need to rebuild VM itself, just one of JFC classes.

Is it possible to build just JFC classes without building whole vm? If so I could replace them in an existing openjdk distribution.

Answer 1

OpenJDK is available either ready to go (as in ready to use) or is available as source.

For what you want to do you'll have to go down the latter route - it really isnt that hard to do. Depending on your machine it'll take from 10mins to an hour, and its mostly by the numbers.

Take a look at The OpenJDK Build Instructions on how to do this.

Note that this is for JDK8, but it applies to JDK7 too (and probably JDK6, although I havent tried that)

Once you've built everything you'll then be able to modify the bits you're actually interested in - I've done this and it works pretty well.