什么是队列

队列是一种基于先进先出(FIFO)的数据结构，是一种只能在一端进行插入,在另一端进行删除操作的特殊线性表，它按照先进先出的原则存储数据，先进入的数据，在读取数据时先读被读出来；

 

代码实现（通过双向链表来实现）

 

public class MyQueue<T> implements Iterable<T>{//记录头结点private Node head;// 记录最后一个结点private Node last;//记录链表的长度private int N;public MyQueue(){this.head = new Node(null,null);this.last = null;this.N = 0;}/***  定义节点类*/public   class Node{T item ;   //存储数据Node next;  //下一个节点public Node(T item, Node next) {this.item = item;this.next = next;}}public void clear(){this.head = null;this.N = 0;}public boolean isEmpty(){return this.N == 0;}public int size(){return this.N;}public T get(){if(isEmpty()){System.out.println("没有数据了");return null;}Node n = this.head.next;this.head.next = n.next;N --;if(isEmpty()){this.head.next=null;this.last = null;}return n.item;}public void push(T t){if(this.head.next == null){last = new Node(t, null);head.next = last;}else {Node oldlast = last;last = new Node(t,null);oldlast.next = last;}N ++;}@Overridepublic Iterator<T> iterator() {return new MyIterator();}private  class MyIterator implements Iterator<T>{Node n = head;@Overridepublic boolean hasNext() {return n.next!=null;}@Overridepublic T next() {n = n.next;return n.item;}}
}