springboot2.x redis lettuce实现分布式锁-白红宇

我查了很多redis分布式锁都是通过jedisclient来实现的，因为springboot2.x默认连接客户端是lettuce，所以引用一个大佬用jedis写的锁修改下。

直接贴代码

1.接口类

public interface DistributedLock {		public static final long TIMEOUT_MILLIS = 30000;		public static final int RETRY_TIMES = 10;		public static final long SLEEP_MILLIS = 500;		public boolean lock(String key);		public boolean lock(String key, int retryTimes);		public boolean lock(String key, int retryTimes, long sleepMillis);		public boolean lock(String key, long expire);		public boolean lock(String key, long expire, int retryTimes);		public boolean lock(String key, long expire, int retryTimes, long sleepMillis);		public boolean releaseLock(String key);}复制代码

2.依然是接口

public abstract class AbstractDistributedLock implements DistributedLock {	@Override	public boolean lock(String key) {		return lock(key , TIMEOUT_MILLIS, RETRY_TIMES, SLEEP_MILLIS);	}	@Override	public boolean lock(String key, int retryTimes) {		return lock(key, TIMEOUT_MILLIS, retryTimes, SLEEP_MILLIS);	}	@Override	public boolean lock(String key, int retryTimes, long sleepMillis) {		return lock(key, TIMEOUT_MILLIS, retryTimes, sleepMillis);	}	@Override	public boolean lock(String key, long expire) {		return lock(key, expire, RETRY_TIMES, SLEEP_MILLIS);	}	@Override	public boolean lock(String key, long expire, int retryTimes) {		return lock(key, expire, retryTimes, SLEEP_MILLIS);	}}复制代码

3.实现类

@Componentpublic class RedisDistributedLock extends AbstractDistributedLock {		@Autowired	@Resource(name="redisTemplateMaster")	private RedisTemplate
    
      redisTemplate;		private final Logger logger = LoggerFactory.getLogger(RedisDistributedLock.class);		//private RedisTemplate
     
       redisTemplate;		private ThreadLocal
      
        lockFlag = new ThreadLocal
       
        ();		public static final String UNLOCK_LUA;    static {        StringBuilder sb = new StringBuilder();        sb.append("if redis.call(\"get\",KEYS[1]) == ARGV[1] ");        sb.append("then ");        sb.append("    return redis.call(\"del\",KEYS[1]) ");        sb.append("else ");        sb.append("    return 0 ");        sb.append("end ");        UNLOCK_LUA = sb.toString();    }        public RedisDistributedLock() {		super();	}//	public RedisDistributedLock(RedisTemplate
        
          redisTemplate) {//		super();//		this.redisTemplate = redisTemplate;//	}	@Override	public boolean lock(String key, long expire, int retryTimes, long sleepMillis) {		boolean result = setRedis(key, expire);		// 如果获取锁失败，按照传入的重试次数进行重试		while((!result) && retryTimes-- > 0){			try {				logger.debug("lock failed, retrying..." + retryTimes);				Thread.sleep(sleepMillis);			} catch (InterruptedException e) {				return false;			}			result = setRedis(key , expire);		}		return result;	}		private boolean setRedis(final String key, final long expire ) {		try{			            RedisCallback
         
           callback = (connection) -> { String uuid = UUID.randomUUID().toString(); lockFlag.set(uuid); return connection.set(key.getBytes(Charset.forName("UTF-8")), uuid.getBytes(Charset.forName("UTF-8")), Expiration.milliseconds(expire), RedisStringCommands.SetOption.SET_IF_ABSENT); }; return (Boolean)redisTemplate.execute(callback); } catch (Exception e) { logger.error("redis lock error.", e); } return false; } @Override public boolean releaseLock(String key) { // 释放锁的时候，有可能因为持锁之后方法执行时间大于锁的有效期，此时有可能已经被另外一个线程持有锁，所以不能直接删除 try { RedisCallback
          
            callback = (connection) -> { String value = lockFlag.get(); return connection.eval(UNLOCK_LUA.getBytes(), ReturnType.BOOLEAN ,1, key.getBytes(Charset.forName("UTF-8")), value.getBytes(Charset.forName("UTF-8"))); }; return (Boolean)redisTemplate.execute(callback); } catch (Exception e) { logger.error("release lock occured an exception", e); } finally { // 清除掉ThreadLocal中的数据，避免内存溢出 lockFlag.remove(); } return false; } }复制代码