Method pollNode

ZezeJava/ZezeJava/src/main/java/Zeze/Collections/Queue.java:209–226

删除并返回整个头节点 @return 头节点，null if empty

()

	 * @return 头节点，null if empty
	 */
	public BQueueNode pollNode() {
		var root = getRoot();
		if (root == null)
			return null;

		var headKey = root.getHeadNodeKey();
		if (headKey.getNodeId() == 0)
			return null;

		var head = getNode(headKey);
		if (head == null)
			return null;

		root.setHeadNodeKey(head.getNextNodeKey());
		root.setCount(root.getCount() - head.getValues().size());
		module._tQueueNodes.remove(headKey);
		return head;
	}

	public void clear() {
		while (pollNode() != null) {