private void releaseForks(Seat crntSeat) {
Fork left = crntSeat.getLeft();
left.getSemaphore().release();
if (crntSeat.equals(seatList.getLast()) && this.client.hasNeighborClient()) {
System.out.println("Philosoph " + this.getPhilosophsId() + " gibt Nachbargabel zurueck!");
this.client.callNeighborToReleaseFork();
} else {
crntSeat.getRight().getSemaphore().release();
}
}
private boolean[] getForks(final Seat seat) {
Fork left = seat.getLeft();
boolean hasRight = false;
boolean hasBoth = false;
boolean exception = false; // fuer Abbruchbedingung, falls anfordern der
// Gabel scheitert
boolean[] hasBoth_exception = new boolean[2];
while (!hasBoth && !exception) {
int tries = 0;
try {
left.getSemaphore().acquire();
} catch (InterruptedException e1) {
System.out.println("This shouldnt happen.");
e1.printStackTrace();
}
while (!hasRight && tries <= Constant.TRIES_TO_GET_FORK) {
if (seat.equals(seatList.getLast())) {
// Unterscheidung ob rechte Gabel lokal oder remote liegt
if (this.client.hasNeighborClient()) {
hasRight = this.client.callNeighborToBlockFork();
} else {
try {
hasRight =
seat.getRight()
.getSemaphore()
.tryAcquire(Constant.TIME_UNTIL_NEW_FORKTRY, TimeUnit.MILLISECONDS);
} catch (InterruptedException | NullPointerException e) {
System.out.println("Fehler beim Anfordern der rechten Gabel!");
e.printStackTrace();
exception = true;
}
}
} else {
try {
hasRight =
seat.getRight()
.getSemaphore()
.tryAcquire(Constant.TIME_UNTIL_NEW_FORKTRY, TimeUnit.MILLISECONDS);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
tries++;
}
hasBoth = hasRight;
if (!hasBoth) {
left.getSemaphore().release();
try {
Thread.sleep(Constant.TIME_UNTIL_NEW_FORKTRY);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
hasBoth_exception[0] = hasBoth;
hasBoth_exception[1] = exception;
return hasBoth_exception;
}