jQuery火箭图标返回顶部代码

public class LinkedQueue
{
    private static final String TAG = "LinkedQueue";
    private int size;
    private QueueNode front = null;
    private QueueNode rear = null;

    class QueueNode
    {
        Object value;
        QueueNode next = null;

        QueueNode(Object obj)
        {
            this.value = obj;
        }

    }

    public boolean isEmpty()
    {
        return size == 0;
    }

    public int getSize()
    {
        return size;
    }

    public void insert(Object obj)//尾巴进入
    {
        QueueNode node = new QueueNode(obj);
        if (front == null && rear == null)//空队列
        {
            node.next = front;
            front = node;
            rear = front;
        } else
        {
            rear.next = node;
            rear = node;
        }
        size++;

    }

    public void delete() throws Exception//头部出来
    {
        if (front == null) throw new Exception("空队列！");
        front = front.next;
        size--;
    }

    public void display() throws Exception//头部出来
    {
        if (front == null) throw new Exception("空队列！");
        QueueNode cur = front;
        while (cur != rear)//还剩一个！
        {
            System.out.print(cur.value + "<-");
            cur = cur.next;
        }
        System.out.println(cur.value);//最后输出！
        System.out.println("");
    }

    public static void main(String[] args) throws Exception
    {
        LinkedQueue lq = new LinkedQueue();
        //lq.display();
        lq.insert("Moab");
        lq.insert("123");
        lq.insert("zhonguo");
        lq.insert("MPY");
        lq.insert("中国！");
        System.out.println(lq.getSize());
        lq.display();
        lq.delete();
        lq.delete();
        lq.delete();
        lq.insert("hha");
        lq.insert("黑长直");
        System.out.println(lq.getSize());
        lq.display();


    }

}