生产者-消费者(有界缓冲区)

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class BoundedBuffer<E> {
final ReentrantLock lock = new ReentrantLock();
final Condition notFull = lock.newCondition();
final Condition notEmpty = lock.newCondition();

final Object[] items = new Object[100];
int putptr, takeptr, count;

public void put(E x) throws InterruptedException {
lock.lock();
try {
while (count == items.length)
notFull.await();
items[putptr] = x;
if (++putptr == items.length) putptr = 0;
++count;
notEmpty.signal();
} finally {
lock.unlock();
}
}

public E take() throws InterruptedException {
lock.lock();
try {
while (count == 0)
notEmpty.await();
E x = (E) items[takeptr];
if (++takeptr == items.length) takeptr = 0;
--count;
notFull.signal();
return x;
} finally {
lock.unlock();
}
}
}