Building nio libraries

[David Holmes]

Can someone tell me what I need to define to be able to build just the 
nio libraries?

I want to do:
make -C make/java/nio  <make-args>

to get libnio.so built.

My initial attempt is failing trying to find btjars/spp.jar which is 
expected to be in the output directory. Is there some special import 
setting, or must I build something else first?

Thanks,
David