//這里輸入的totalMoney單位是分,例如100元,totalMoney = 10000
public List<Integer> getRedPackage(Integer totalMoney,Integer totalPeopleCount) {
    List<Integer> moneyList = new ArrayList<>();
    //暫存剩余金額為紅包的總金額
    Integer restMoney = totalMoney;
    //暫存剩余的總?cè)藬?shù)-初始化時即為指定的總?cè)藬?shù)
    Integer restPeopleCount = totalPeopleCount;    
    //隨機數(shù)對象
    Random random = new Random();
    //開始循環(huán)迭代生成紅包
    for (int i =0;i< totalPeopleNum-1;i++){
       //加1是為了至少搶到1分錢
       int money = random.nextInt (restMoney / restPeopleCount * 2) + 1;
       restMoney -= money;
       restPeopleCount--;
       moneyList.add(money);
    }
    //添加最后的一個紅包金額
    amountList.add(restAmount);
    return amountList;
}

//隨機生成全局唯一的紅包id
redId = getRedId();
//首先生成紅包金額
List<Integer> moneyList = getRedPackage(totalMoney,totalPeopleCount);
//放入redis
redisClient.lpush(redId, moneyList);
//redis中記錄紅包個數(shù)
redisClient.set(redId, moneyList.size());
//異步存儲發(fā)紅包記錄到Mysql數(shù)據(jù)庫
//將紅包id返回
return redId;

redMoney = redisClient.get("rob" + redId + useId)
//如果不為空,則說明已經(jīng)搶過了,直接返回?fù)屵^的紅包金額
if (redMoney != null) {
    return redMoney
}

totalNum = redisClient.get("totalNum" + redId)
//如果為空或者小于等于0則代表沒有了
if (totalNum == null || totalNum <= 0) {
    return null
}

money = redisClient.rpop(redId)
//如果不為空,則說明搶到了
if (money != null) {
    ....
    紅包個數(shù)減1
    存儲搶紅包記錄
    設(shè)置該用戶已經(jīng)搶過紅包
    ....
    //返回?fù)尩降慕痤~
    return money
}
//沒搶到
return null

money = redisClient.rpop(redId)
//如果不為空,則說明搶到了
if (money != null) {
    //紅包個數(shù)減1
    redisClient.decr(redId)
    ....
    存儲搶紅包記錄
    設(shè)置該用戶已經(jīng)搶過紅包
    ....
    //返回?fù)尩降慕痤~
    return money
}
//沒搶到
return null

money = redisClient.rpop(redId)
//如果不為空,則說明搶到了
if (money != null) {
    //紅包個數(shù)減1
    redisClient.decr(redId)
    //異步存儲搶紅包記錄
    這里可以使用mq或者多線程的方式來實現(xiàn)
    ....
    設(shè)置該用戶已經(jīng)搶過紅包
    ....
    //返回?fù)尩降慕痤~
    return money
}
//沒搶到
return null

money = redisClient.rpop(redId)
//如果不為空,則說明搶到了
if (money != null) {
    //紅包個數(shù)減1
    redisClient.decr(redId)
    //異步存儲搶紅包記錄
    這里可以使用mq或者多線程的方式來實現(xiàn)
    //設(shè)置該用戶已經(jīng)搶過紅包
    redisClient.set("rob" + redId + useId, money)
    //返回?fù)尩降慕痤~
    return money
}
//沒搶到
return null

redMoney = redisClient.get("rob" + redId + useId)
//如果不為空,則說明已經(jīng)搶過了,直接返回?fù)屵^的紅包金額
if (redMoney != null) {
    return redMoney
}
totalNum = redisClient.get("totalNum" + redId)
//如果紅包總數(shù)小于0, 則代表已經(jīng)搶完了, 直接返回空
if (totalNum == null || totalNum <= 0) {
    return null
}
money = redisClient.rpop(redId)
//如果不為空,則說明搶到了
if (money != null) {
    //紅包個數(shù)減1
    redisClient.decr(redId)
    //異步存儲搶紅包記錄
    這里可以使用mq或者多線程的方式來實現(xiàn)
    //設(shè)置該用戶已經(jīng)搶過紅包
    redisClient.set("rob" + redId + useId, money)
    //返回?fù)尩降慕痤~
    return money
} 
//沒搶到
return null

redMoney = redisClient.get("rob" + redId + useId)
//如果不為空,則說明已經(jīng)搶過了,直接返回?fù)屵^的紅包金額
if (redMoney != null) {
    return redMoney
}
totalNum = redisClient.get("totalNum" + redId)
//如果紅包總數(shù)小于0, 則代表已經(jīng)搶完了, 直接返回空
if (totalNum == null || totalNum <= 0) {
    return null
}
//加分布式鎖
lockResut = redisClient.setNx(useId,redId,timeOut);
//加鎖失敗,直接返回
if(!lockResult){
    return;
}
try{
    money = redisClient.rpop(redId)
    //如果不為空,則說明搶到了
    if (money != null) {
        //紅包個數(shù)減1
        redisClient.decr(redId)
        //異步存儲搶紅包記錄
        這里可以使用mq或者多線程的方式來實現(xiàn)
        //設(shè)置該用戶已經(jīng)搶過紅包
        redisClient.set("rob" + redId + useId, money)
        //返回?fù)尩降慕痤~
        return money
    }     
} finally {
    //刪除鎖
    redisClient.del(useId)
}
//沒搶到
return null