Java单链表实现队列

• 示意图（队列横向，栈竖向好看；链表实现队列不用给初始化尺寸，不担心溢出）
  
• 代码

public class LinkedQueue{

    Node front;
    Node rear;

    public LinkedQueue() {
        this.front = null;
        this.rear = null;
    }

    public boolean inQueue(int value) {
        Node node = new Node(value);
        if (front == null) {
            front = node;
            rear = front;
        } else {
            rear.next = node;
            rear = node;
        }
        return true;
    }

    public int outQueue() {
        if (front == null) {
            System.out.println("当前队列为空");
            return -1;
        }
        int data = front.data;
        front = front.next;
        return  data;
    }

    public static void main(String[] args) {
        LinkedQueue queue = new LinkedQueue();
        queue.inQueue(1);
        queue.inQueue(2);
        queue.inQueue(3);
        queue.outQueue();
        while (queue.front != null) {
            System.out.println(queue.front.data);
            queue.front = queue.front.next;
        }
    }
}

class Node {
    Node next;
    int data;

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

• 结果