利用java通过循环单链表设计队列的代码怎么写

以下是利用Java通过循环单链表设计队列的代码：

public class Queue {

    private Node front; //队头
    private Node rear;  //队尾
    private int size;   //队列大小

    //定义节点类Node
    private class Node {
        private Object data;
        private Node next;

        public Node(Object data) {
            this.data = data;
        }
    }

    /**
     * 判断队列是否为空
     */
    public boolean isEmpty() {
        return size == 0;
    }

    /**
     * 获取队列大小
     */
    public int getSize() {
        return size;
    }

    /**
     * 入队
     */
    public void enqueue(Object obj) {
        Node node = new Node(obj);
        if(isEmpty()){
            front = node;
            rear = node;
            rear.next = front;  //队尾指向队头
        }else{
            rear.next = node;
            rear = node;
            rear.next = front;  //队尾指向队头
        }
        size++;
    }

    /**
     * 出队
     */
    public Object dequeue() {
        if(isEmpty()){
            throw new RuntimeException("队列为空！");
        }
        Object obj = front.data;
        if(size == 1){
            front = null;
            rear = null;
        }else{
            front = front.next;
            rear.next = front; //队尾指向队头
        }
        size--;
        return obj;
    }
}