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@Service
@Slf4j
public class DistributedLockService {
@Autowired
private RedisTemplate<String, Object> redisTemplate;
private static final String LOCK_SCRIPT =
"if redis.call('get', KEYS[1]) == ARGV[1] then " +
"return redis.call('del', KEYS[1]) " +
"else " +
"return 0 " +
"end";
private static final String UNLOCK_SCRIPT =
"if redis.call('get', KEYS[1]) == ARGV[1] then " +
"return redis.call('del', KEYS[1]) " +
"else " +
"return 0 " +
"end";
public boolean tryLock(String lockKey, String lockValue, long expireTime, TimeUnit timeUnit) {
try {
Boolean success = redisTemplate.opsForValue().setIfAbsent(lockKey, lockValue,
expireTime, timeUnit);
return success != null && success;
} catch (Exception e) {
log.error("获取锁失败: lockKey={}", lockKey, e);
return false;
}
}
public boolean lock(String lockKey, String lockValue, long expireTime, TimeUnit timeUnit) {
return lock(lockKey, lockValue, expireTime, timeUnit, 30, TimeUnit.SECONDS);
}
public boolean lock(String lockKey, String lockValue, long expireTime, TimeUnit timeUnit,
long waitTime, TimeUnit waitTimeUnit) {
long startTime = System.currentTimeMillis();
long waitTimeMillis = waitTimeUnit.toMillis(waitTime);
while (System.currentTimeMillis() - startTime < waitTimeMillis) {
if (tryLock(lockKey, lockValue, expireTime, timeUnit)) {
return true;
}
try {
Thread.sleep(100);
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
return false;
}
}
return false;
}
public boolean releaseLock(String lockKey, String lockValue) {
try {
DefaultRedisScript<Long> script = new DefaultRedisScript<>();
script.setScriptText(UNLOCK_SCRIPT);
script.setResultType(Long.class);
Long result = redisTemplate.execute(script, Collections.singletonList(lockKey), lockValue);
return result != null && result == 1;
} catch (Exception e) {
log.error("释放锁失败: lockKey={}", lockKey, e);
return false;
}
}
public boolean renewLock(String lockKey, String lockValue, long expireTime, TimeUnit timeUnit) {
try {
String currentValue = (String) redisTemplate.opsForValue().get(lockKey);
if (lockValue.equals(currentValue)) {
redisTemplate.expire(lockKey, expireTime, timeUnit);
return true;
}
return false;
} catch (Exception e) {
log.error("续期锁失败: lockKey={}", lockKey, e);
return false;
}
}
}
@Component
@Slf4j
public class ReentrantDistributedLock {
@Autowired
private RedisTemplate<String, Object> redisTemplate;
private final ThreadLocal<Map<String, Integer>> lockCount = new ThreadLocal<>();
public boolean lock(String lockKey, String lockValue, long expireTime, TimeUnit timeUnit) {
Map<String, Integer> countMap = lockCount.get();
if (countMap == null) {
countMap = new HashMap<>();
lockCount.set(countMap);
}
Integer count = countMap.get(lockKey);
if (count != null && count > 0) {
countMap.put(lockKey, count + 1);
return true;
}
Boolean success = redisTemplate.opsForValue().setIfAbsent(lockKey, lockValue,
expireTime, timeUnit);
if (success != null && success) {
countMap.put(lockKey, 1);
return true;
}
return false;
}
public boolean unlock(String lockKey, String lockValue) {
Map<String, Integer> countMap = lockCount.get();
if (countMap == null) {
return false;
}
Integer count = countMap.get(lockKey);
if (count == null || count <= 0) {
return false;
}
if (count > 1) {
countMap.put(lockKey, count - 1);
return true;
}
String currentValue = (String) redisTemplate.opsForValue().get(lockKey);
if (lockValue.equals(currentValue)) {
redisTemplate.delete(lockKey);
countMap.remove(lockKey);
return true;
}
return false;
}
}
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