Subsequent EJB server-calls within one Thread?

Question

Hi all,
will all subsequent EJB calls within the server be executed within the same Thread? I didn't find an exact spec of this.
The context is that i have remote and local stateless session beans and i want to share the timestamp at which the initial service call took place. So i thought about setting a ThreadLocal variable by an Interceptor and read this in every bean.
Maybe there is a better way to do this?
Thanks in advance,
Andreas

Answer 1

I'm not sure why you make each car a Thread when you later come along to create ActionThreads to do the work. It seems to me as if there is at least one Thread too many.
Nonetheless, this peace of code is most likely not a good implementation of what you are trying to do:
sleeping = true;
while (sleeping) {
  try {
    car.sleep(0);
  catch (InterruptedException ex)  {}
}The reasons being:
You are working with several concurrent Threads acting upon the same Cars, the master Thread, the Cars themselves and the ActionThreads. So you will need some synchronization to ensure consistency. You are using none! If you were, a call to sleep() would block the monitor of your Car instance.
You are using the while loop to implement busy waiting. A bad choice by itself, it might lock your VM totally if this Thread gets a high priority for some reason. What you actually want to use is a wait()-notify-pair jointly with proper synchronization.
http://java.sun.com/docs/books/tutorial/essential/threads/multithreaded.html