基于Redis实现类似微信抢红包

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<String, String> connection = redisClient.connect();
		RedisCommands<String, String> 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<String, String> connection = redisClient.connect();
		RedisCommands<String, String> 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：