基於Redis實現類似微信搶紅包

一個簡單的基於Redis實現搶紅包功能，分為兩個步驟：

1、拆分紅包

	/**
	 * 拆紅包 1、紅包金額要被全部拆分完 2、紅包金額不能差的太離譜
	 * 
	 * @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 紅包隨機金額浮動系數
				array[i] = 1 + random.nextInt(avg - 1);
			}
			use = use + array[i];
		}
		return array;
	}

2、保存紅包

	/**
	 * 存紅包 采用redis的list結構
	 * 
	 * @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、搶紅包

	/**
	 * 搶紅包
	 * 
	 * @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("搶到紅包：" + res);
		connection.close();
		redisClient.shutdown();
	}

 

最后完整測試demo如下：

public static void main(String[] args) {
		final String packetId = UUID.randomUUID().toString();
		// 紅包金額(以分為單位，無精度損失問題)
		int total = 2000;
		// 紅包數量
		int count = 7;
		// 拆紅包
		int[] packets = SplitRedPacket(total, count);
		// 存紅包
		SaveRedPacket(packetId, packets);

		// 搶紅包
		ExecutorService cachedThreadPool = Executors.newCachedThreadPool();
		for (int i = 0; i < 20; i++) {
			cachedThreadPool.execute(new Runnable() {
				public void run() {
					GrabRedPacket(packetId);
				}
			});
		}
	}

　測試結果：