使用信号量Semaphore设置容器边界

class BoundedHashSet<T>{private final Set<T> set;private final Semaphore semaphore;public BoundedHashSet(int bound) {set = Collections.synchronizedSet(new HashSet<T>());semaphore = new Semaphore(bound);}public boolean add(T t) throws InterruptedException{semaphore.acquire();boolean wasAdded = set.add(t);if (!wasAdded) {semaphore.release();}return wasAdded;}public boolean remove(T t){boolean wasRemoved = set.remove(t);if (wasRemoved) {semaphore.release();}return wasRemoved;}}