jsp + java抽奖demo

package com.ostarsier.servlet; import java.io.IOException; import java.util.Random; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; /** * 抽奖 */ public class AwardServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { Object[][] prizeArr = new Object[][]{ //id, min, max,prize【奖项】,v【中奖率】 //min,max 可以为0 //外面的转盘转动 //里面的指针转动 {1,1,14,"一等奖",1}, {2,346,364,"一等奖",1}, {3,16,44,"不要灰心",10}, {4,46,74,"神马也没有",10}, {5,76,104,"祝您好运",10}, {6,106,134,"二等奖",2}, {7,136,164,"再接再厉",10}, {8,166,194,"神马也没有",10}, {9,196,224,"运气先攒着",10}, {10,226,254,"三等奖",5}, {11,256,284,"要加油哦",10}, {12,286,314,"神马也没有",10}, {13,316,344,"谢谢参与",10} }; Object result[] = award(prizeArr);//抽奖后返回角度和奖品等级 response.setContentType("text/html;charset=UTF-8"); response.getWriter().write("{\"angle\":\""+result[0]+"\",\"msg\":\""+result[2]+"\"}"); System.out.println("转动角度:"+result[0]+"\t奖项ID:"+result[1]+"\t提示信息:"+result[2]); } //抽奖并返回角度和奖项 public Object[] award(Object[][] prizeArr){ //概率数组 Integer obj[] = new Integer[prizeArr.length]; for(int i=0;i<prizeArr.length;i++){ obj[i] = (Integer) prizeArr[i][4]; } Integer prizeId = getRand(obj); //根据概率获取奖项id //旋转角度 int angle = new Random().nextInt((Integer)prizeArr[prizeId][2]-(Integer)prizeArr[prizeId][1])+(Integer)prizeArr[prizeId][1]; String msg = (String) prizeArr[prizeId][3];//提示信息 return new Object[]{angle,prizeId,msg}; } //根据概率获取奖项 public Integer getRand(Integer obj[]){ Integer result = null; try { int sum = 0;//概率数组的总概率精度 for(int i=0;i<obj.length;i++){ sum+=obj[i]; } for(int i=0;i<obj.length;i++){//概率数组循环 int randomNum = new Random().nextInt(sum);//随机生成1到sum的整数 if(randomNum<obj[i]){//中奖 result = i; break; }else{ sum -=obj[i]; } } } catch (Exception e) { e.printStackTrace(); } return result; } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }