"platform modules"

[Jonathan Gibbons]

Alex,

We need to tie down where platform (java.lang.* etc) classes come  
from, and what potential
there is to override any system defaults.

For example, what is the relationship between -source, -target and  
platform class path?

If I run a JDK 8 javac with -source 7, do I get a JDK7 platform path?

If I run a JDK 8 javac and specify a version 7 platform in my module- 
info, is that legal?
Is there any interaction of check with -source? What if JDK 8  
introduces language features
that require new JDK 8 api.

Now, repeat questions for java, not javac ;-)

-- Jon