public Object poll(long msecs) throws InterruptedException {
if (Thread.interrupted()) throw new InterruptedException();
if (!takeGuard_.attempt(msecs)) return null;
else {
try {
Object x = extract();
putGuard_.release();
return x;
} catch (ClassCastException ex) {
takeGuard_.release();
throw ex;
}
}
}
public boolean offer(Object x, long msecs) throws InterruptedException {
if (x == null) throw new IllegalArgumentException();
if (Thread.interrupted()) throw new InterruptedException();
if (!putGuard_.attempt(msecs)) return false;
else {
try {
insert(x);
takeGuard_.release();
return true;
} catch (ClassCastException ex) {
putGuard_.release();
throw ex;
}
}
}