Pool de recursos: solução para clientes que pedem diversos recursos

 
ResourcePool pool;

...

myResource = pool.getResource();

/* use myResource */

pool.releaseResource(myResource);

...

class ResourcePool {

		 Queue available = new Queue();

		 TicketQueue waiting = new Queue();

		 ResourceList getResource(int nr) {

		 		 lock(mutex);

		 		 int myTicket = ticket++;

		 		 while ( available.size() < nr ) 

		 		 (!waiting.iAmTheBest(myTicket)) ) {

		 		 		 waiting.enter(myTicket, mutex);

		 		 }

		 		 ResourceList rl = available.getList(nr);

		 		 waiting.ok(myTicket);

		 		 unlock(mutex);

		 		 return rl;

		 }

		 void releaseResource(ResourceList rl) {

		 		 lock(mutex);

		 		 available.put(rl);

		 		 waiting.select(mutex);

		 		 unlock(mutex);

		 }

}