if(!SessionPool.pool.containsKey(sess_id))
res_builder.setSuccess(false).setException("invalid session id " + sess_id);
else {
try {
Session sess = SessionPool.getOrCreateConcreteSession(sess_id, greq.getRole());
sess.attach(greq.getRole());
res_builder.setSuccess(true).setContext(new Integer(sess.getCommPort()).toString());
}
catch(MistException e) {
res_builder.setSuccess(false).setException(e.getMessage());
}