- All Implemented Interfaces:
public class FIFOSemaphore
- extends QueuedSemaphore
A First-in/First-out implementation of a Semaphore.
Waiting requests will be satisified in
the order that the processing of those requests got to a certain point.
If this sounds vague it is meant to be. FIFO implies a
logical timestamping at some point in the processing of the
request. To simplify things we don't actually timestamp but
simply store things in a FIFO queue. Thus the order in which
requests enter the queue will be the order in which they come
out. This order need not have any relationship to the order in
which requests were made, nor the order in which requests
actually return to the caller. These depend on Java thread
scheduling which is not guaranteed to be predictable (although
JVMs tend not to go out of their way to be unfair).
[ Introduction to this package. ]
Create a Semaphore with the given initial number of permits.
|Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
public FIFOSemaphore(long initialPermits)
- Create a Semaphore with the given initial number of permits.
Using a seed of one makes the semaphore act as a mutual exclusion lock.
Negative seeds are also allowed, in which case no acquires will proceed
until the number of releases has pushed the number of permits past 0.