A well behaved application will not call any write methods on
AsyncContext.getResponse().getWriter() after AsyncContext.complete() has been
called. That said, Glassfish should handle the situation with a IOException,
WARNING: Interrupting idle Thread: Grizzly-kernel-thread-21072(1)
WARNING: Channel was unexpectedly closed
resulting in the server refusing any more connections.
Perhaps the OutputStream is not being closed properly?