一个简单的基于Redis实现抢红包功能，分为两个步骤：

1、拆分红包

/**

* 拆红包 1、红包金额要被全部拆分完 2、红包金额不能差的太离谱

*

* @param total

* @param count

* @return

*/

public static int[] SplitRedPacket(int total, int count) {

int use = 0;

int[] array = new int[count];

Random random = new Random();

for (int i = 0; i < count; i++) {

if (i == count - 1)

array[i] = total - use;

else {

int avg = (total - use) * 2 / (count - i);// 2 红包随机金额浮动系数

array[i] = 1 + random.nextInt(avg - 1);

}

use = use + array[i];

}

return array;

}

2、保存红包

/**

* 存红包 采用redis的list结构

*

* @param packetId

* @param packets

*/

public static void SaveRedPacket(String packetId, int[] packets) {

RedisClient redisClient = RedisClient.create("redis://127.0.0.1:6379/0");

StatefulRedisConnection connection = redisClient.connect();

RedisCommands syncCommands = connection.sync();

for (int packet : packets) {

syncCommands.lpush("Packet:" + packetId, packet + "");

}

connection.close();

redisClient.shutdown();

}

3、抢红包

/**

* 抢红包

*

* @param packetId

*/

public static void GrabRedPacket(String packetId) {

RedisClient redisClient = RedisClient.create("redis://127.0.0.1:6379/0");

StatefulRedisConnection connection = redisClient.connect();

RedisCommands syncCommands = connection.sync();

String res = syncCommands.lpop("Packet:" + packetId);

System.out.println("抢到红包：" + res);

connection.close();

redisClient.shutdown();

}

最后完整测试demo如下：

public static void main(String[] args) {

final String packetId = UUID.randomUUID().toString();

// 红包金额(以分为单位，无精度损失问题)

int total = 2000;

// 红包数量

int count = 7;

// 拆红包

int[] packets = SplitRedPacket(total, count);

// 存红包

SaveRedPacket(packetId, packets);

// 抢红包

ExecutorService cachedThreadPool = Executors.newCachedThreadPool();

for (int i = 0; i < 20; i++) {

cachedThreadPool.execute(new Runnable() {

public void run() {

GrabRedPacket(packetId);

}

});

}

}

测试结果：