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@Component
public class RedisLock {

private static final Long RELEASE_SUCCESS = 1L;
private static final String LOCK_SUCCESS = “OK”;
private static final String SET_IF_NOT_EXIST = “NX”;
// 当前设置 过期时间单位, EX = seconds; PX = milliseconds
private static final String SET_WITH_EXPIRE_TIME = “EX”;
//lua
private static final String RELEASE_LOCK_SCRIPT = “if redis.call(‘get’, KEYS[1]) == ARGV[1] then return redis.call(‘del’, KEYS[1]) else return 0 end”;

@Autowired
private StringRedisTemplate redisTemplate;

/**

• 该加锁方法仅针对单实例 Redis 可实现分布式加锁
• 对于 Redis 集群则无法使用
• 支持重复，线程安全
  *
• @param lockKey 加锁键
• @param clientId 加锁客户端唯一标识(采用UUID)
• @param seconds 锁过期时间
• @return
  */
  public boolean tryLock(String lockKey, String clientId, long seconds) {
  return redisTemplate.execute((RedisCallback) redisConnection -> {
  // Jedis jedis = (Jedis) redisConnection.getNativeConnection();
  Object nativeConnection = redisConnection.getNativeConnection();
  RedisSerializer stringRedisSerializer = (RedisSerializer) redisTemplate.getKeySerializer();
  byte[] keyByte = stringRedisSerializer.serialize(lockKey);
  byte[] valueByte = stringRedisSerializer.serialize(clientId);

// lettuce连接包下 redis 单机模式
      if (nativeConnection instanceof RedisAsyncCommands) {
          RedisAsyncCommands connection = (RedisAsyncCommands) nativeConnection;
          RedisCommands commands = connection.getStatefulConnection().sync();
          String result = commands.set(keyByte, valueByte, SetArgs.Builder.nx().ex(seconds));
          if (LOCK_SUCCESS.equals(result)) {
              return true;
          }
      }
      // lettuce连接包下 redis 集群模式
      if (nativeConnection instanceof RedisAdvancedClusterAsyncCommands) {
          RedisAdvancedClusterAsyncCommands connection = (RedisAdvancedClusterAsyncCommands) nativeConnection;
          RedisAdvancedClusterCommands commands = connection.getStatefulConnection().sync();
          String result = commands.set(keyByte, valueByte, SetArgs.Builder.nx().ex(seconds));
          if (LOCK_SUCCESS.equals(result)) {
              return true;
          }
      }

      if (nativeConnection instanceof JedisCommands) {
          JedisCommands jedis = (JedisCommands) nativeConnection;
          String result = jedis.set(lockKey, clientId, SET_IF_NOT_EXIST, SET_WITH_EXPIRE_TIME, seconds);
          if (LOCK_SUCCESS.equals(result)) {
              return true;
          }
      }
      return false;
  });

• 
  } /**
• 与 tryLock 相对应，用作释放锁
  *
• @param lockKey
• @param clientId
• @return
  */
  public boolean releaseLock(String lockKey, String clientId) {
  DefaultRedisScript redisScript = new DefaultRedisScript<>();
  redisScript.setScriptText(RELEASE_LOCK_SCRIPT);
  redisScript.setResultType(Integer.class);
  // Integer execute = redisTemplate.execute(redisScript, Collections.singletonList(lockKey), clientId); Object execute = redisTemplate.execute((RedisConnection connection) -> connection.eval(
  RELEASE_LOCK_SCRIPT.getBytes(),
  ReturnType.INTEGER,
  1,
  lockKey.getBytes(),
  clientId.getBytes()));
  if (RELEASE_SUCCESS.equals(execute)) {
  return true;
  }
  return false;
  }
  }