SpringBoot Redis 分布式锁

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我是靠谱客的博主结实枕头，最近开发中收集的这篇文章主要介绍SpringBoot Redis 分布式锁，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1.SpringMVC用jedis实现方式

   /**
     * 获取分布式锁
     * @param lockKey 锁
     * @param value 请求标识
     * @param expireTime 超期时间
     *  NX 仅当键值不存在时设置
     *  PX 超时时间单位：毫秒
     * @return 是否获取成功
     */
    public boolean getLock(String lockKey, String value, int expireTime) {
        String result = this.getJedis().set(lockKey, value, "NX", "PX", expireTime);
        if ("OK".equals(result)) {
            return true;
        }
        return false;
    }
    
   /**
     * 释放分布式锁-使用lua表达保证原子性
     */
    public boolean unlock(String key, String value) {
        String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
        Object result = this.getJedis().eval(script, Collections.singletonList(key), Collections.singletonList(value));
        if ("OK".equals(result)) {
            return true;
        }
        return false;
    }

2.springboot用RedisTemplate实现方式

/**
     * 获取分布式锁
     *
     * @param lockKey 锁名称
     * @param value   值
     * @param expire  过期时间
     * @param timeout 等待超时时间
     * @return 是否获取成功
     */
    public boolean getLock(String lockKey, String value, long expire, long timeout) {
        //获取当前毫米数
        long startTime = System.currentTimeMillis();
        String script = "if redis.call('setNx',KEYS[1],ARGV[1]) == 1 then " +
                "if redis.call('get',KEYS[1]) == ARGV[1] then " +
                "return redis.call('expire',KEYS[1],ARGV[2]) else return 0 end else return 0 end";

        RedisScript<Long> redisScript = new DefaultRedisScript<>(script, Long.class);

        Long execute = redisTemplate.execute(redisScript, Collections.singletonList(lockKey), Collections.singletonList(value), expire);
        if (1l == execute.longValue()) {
            return true;
        } else {
            long endTime = System.currentTimeMillis();
            if ((endTime - startTime) > timeout) {
                return false;
            }
        }
        return false;
    }

    /**
     * 释放分布式锁-使用lua表达保证原子性
     */
    public boolean unlock(String key, String value) {
        String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
        RedisScript<Long> redisScript = new DefaultRedisScript<>(script, Long.class);
        Long result = redisTemplate.execute(redisScript, Collections.singletonList(key), Collections.singletonList(value));
        if (1l == result.longValue()) {
            return true;
        }
        return false;
    }

3. 用法

public void myService(String orderNumber) {
        Long pickupCode = null;
        String val = UUID.randomUUID().toString().replace("-","");
        try {
            //获取锁
            boolean lock = redisTemplateService.getLock(orderNumber, val, 10, 10);
            if (lock) {
                pickupCode = pickupHandler(orderNumber);//业务逻辑
            } else {
                Thread.sleep(100);
                gainPickupCode(orderNumber);//没获取到递归继续获取
            }

        } catch (InterruptedException e) {
            e.printStackTrace();
        } finally {
            //释放锁
            redisTemplateService.unlock(orderNumber, val);
        }
    }