数组实现队列

package com.gaiwey.algorithm;/*** 用数组实现队列：固定长度的数组，数组类型随意，我用的int实现* 难点在于控制入队和出队的索引* @author 嚼不烂菠菜*/
public class MyQueue {private int[] arr;// 存放数据的数组private int size; // 数组长度private int pushindex;// 添加元素的索引位置private int pollindex;// 取出元素的索引位置private int limit;// 数组长度限制public MyQueue(int limit) {arr = new int[limit];size = 0;pushindex = 0;pollindex = 0;this.limit = limit;}public void push(int i) {// 检查队列满没满if (isFull()) {throw new RuntimeException("队列已满，无法添加元素啦……");}arr[pushindex] = i;size++;pushindex = nextIndex(pushindex);}public int poll() {// 检查队列是否为空if (isEmpty()) {throw new RuntimeException("队列已空，无法取出元素啦……");}int i = arr[pollindex];size--;pollindex = nextIndex(pollindex);return i;}/*** 队列是否已空* @return true-空；false-不为空*/public boolean isEmpty(){return size==0?true:false;}/*** 队列是否已满* @return true;false*/public boolean isFull(){return size==limit?true:false;}/*** 获取当前传入索引的下一个位置* @param i 当前索引* @return*/private int nextIndex(int i){return i < arr.length - 1 ? i + 1 : 0;}
}