(3)同理,检测(Examine)元素的动作,返回头部元素(最开始加入的元素),但不删除元素, 如果队列为空,则 element () 方法抛异常,而 peek () 返回 false。 (4)Queue 接口没有定义阻塞队列的方法,这些方法在 BlockQueue 接口中定义了。 (5)Queue 实现类通常不允许插入 null 元素,尽管一些实现类比如 LinkedList 不...
add/offer:用于向队列中添加元素,add 在队列满时抛出异常,offer 在队列满时返回 false。 element/peek:用于获取队列的头部元素,element 在队列为空时抛出异常,peek 在队列为空时返回 null。 remove/poll:用于删除并返回队列的头部元素,如果队列为空则返回 null。这两个方法在功能上是相同的。 了解这些方法的区别和...
Queue中常用的element/peek,remove/poll,add/offer有什么不同 虽然ArrayList底层是数组,但是优化之后的增删操作依然不慢,这就使得LindedList的很少出现在我们视野当中。但是在涉及到Stack和Queue时候(主要是刷题时),LinkedList的还是很常见的,由于底层是双向链表,又实现了Deque接口,经常被繁多的方法搞得头晕,主要方法如...
element() 和 peek() 用于在队列的头部查询元素。与 remove() 方法类似,在队列为空时, element() 抛出一个异常,而 peek() 返回 null
在队列为空时, element() 抛出一个异常,而 peek() 返回 null offer()和add() 添加元素 add(): boolean add(E e)将指定的元素插入到此队列中,如果可以立即执行此操作而不违反容量限制, true在成功后返回 IllegalStateException如果当前没有可用空间,则抛出IllegalStateException。
ELEMENT= Specifies the address of the element to be removed from the queue. If the address is not specified, the first element is removed. ELEMENT and ELEMENT_ALET are mutually exclusive. ELEMENT_ALET= Specifies the ALET of the element to be removed. ELEMENT and ELEMENT_ALET are mutually exc...
Queue is empty" << endl; // Display error if the queue is empty return -1; } return arr[front]; // Returns the element at the front of the queue } void display() { if (isEmpty()) { cout << "Error: Queue is empty" << endl; // Display error if the queue is empty return...
NoSuchElementException if this queue is empty Remarks Retrieves and removes the head of this queue. This method differs from #poll poll only in that it throws an exception if this queue is empty. This implementation returns the result of poll unless the queue is empty. Java documentation for...
Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque). [Android.Runtime.Register("remove", "()Ljava/lang/Object;", "GetRemoveHandler")] public virtual Java.Lang.Object? Remove(); ...
The KeRemoveDeviceQueue routine removes an entry from the head of a specified device queue.SyntaxC++ Kopírovat PKDEVICE_QUEUE_ENTRY KeRemoveDeviceQueue( [in, out] PKDEVICE_QUEUE DeviceQueue ); Parameters[in, out] DeviceQueuePointer to an initialized device queue object for which the caller ...