Re: Proposal for changes to Classpath's JNI libraries

[Artur Biesiadowski]

Stephen Crawley wrote:

> Those of you have been following the Kissme mailing list will know
> that we've had a long-standing problem with Kissme garbage collection
> and IO.  In a nutshell, the Kissme garbage collector can only run
> when all threads are within a "GC point".  Normal Java code regularly
> enters (and exits) GC points, and native code will get there eventually.


As far as I understand one of basic concepts behind JNI, idea behind 
local/global references mess one exactly meant to provide a help for gc. 
Call to native method can be marked as safe (all call areas have to be 
fully resolved to allow gc for upper frames). Inside JNI, nothing bad 
can happen - all references to java objects are managed through JNI 
itself, which is fully under your control.

Why careful design of JNI layer cannot solve the problem here ?

You cannot expect all people out there to write their JNI libraries 
wrapping any potentially blocking calls into your calls (I'm talking 
about third party libraries).

Artur