this(capacity, fair);
if (capacity < c.size())
throw new IllegalArgumentException();
for (Iterator< extends E> it = c.iterator(); it.hasNext();)
add(it.next());
}
/**
* 插入元素到队尾（super调用offer方法）
* public boolean add(E e) {
* if (offer(e))
* return true;
* else
* throw new IllegalStateException("Queue full");
* }
* 将指定的元素插入到此队列的尾部（如果立即可行且不会超过该队列的容量），
* 在成功时返回 true，如果此队列已满，则抛出 IllegalStateException。
*/
public boolean add(E e) {
return super.add(e);
}
/**
* 将指定的元素插入到此队列的尾部（如果立即可行且不会超过该队列的容量），
* 在成功时返回 true，如果此队列已满，则返回 false。
*/
public boolean offer(E e) {
if (e == null) throw new NullPointerException();
final ReentrantLock lock = this.lock;
lock.lock();
try {
if (count == items.length)
return false;
else {
insert(e);
return true;
}
} finally {
lock.unlock();
}
}
/**
* 将指定的元素插入此队列的尾部，如果该队列已满，则等待可用的空间。
*/
public void put(E e) throws InterruptedException {
if (e == null) throw new NullPointerException();
final E[] items = this.items;
final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
try {
while (count == items.length)
notFull.await();
} catch (InterruptedException ie) {
notFull.signal(); // propagate to non-interrupted thread
throw ie;
}
} finally {
lock.unlock();
}
}
/**
* 将指定的元素插入此队列的尾部，如果该队列已满，则在到达指定的等待时间之前等待可用的空间。
*/
public boolean offer(E e, long timeout, TimeUnit unit)
throws InterruptedException {
if (e == null) throw new NullPointerException();
long nanos = unit.toNanos(timeout);
final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
for (;;) {
if (count != items.length) {
insert(e);
return true;
}
if (nanos <= 0)//如果时间到了就返回
return false;
try {
nanos = notFull.awaitNanos(nanos);
} catch (InterruptedException ie) {
notFull.signal(); // propagate to non-interrupted thread
throw ie;
}
}
} finally {
lock.unlock();
}
}
//获取并移除此队列的头，如果此队列为空，则返回 null。
public E poll() {
final ReentrantLock lock = this.lock;
lock.lock();
try {
if (count == 0)
return null;
E x = extract();
return x;
} finally {
lock.unlock();
}
}
//获取并移除此队列的头部，在元素变得可用之前一直等待（如果有必要）。
public E take() throws InterruptedException {
final ReentrantLock lock = this.lock;
lock.lockInterruptibly();
try {
try {
while (count == 0)
notEmpty.await();