import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.ValueOperations;
import org.springframework.stereotype.Component;
import java.util.concurrent.TimeUnit;
@Component
public class DistributedLockService {
    private final RedisTemplate<String, String> redisTemplate;
    public DistributedLockService(RedisTemplate<String, String> redisTemplate) {
        this.redisTemplate = redisTemplate;
    }
    /**
     * 嘗試獲取鎖。
     * @param lockKey 鎖的key
     * @param requestId 請求標識，用于解鎖時驗證
     * @param expireTime 超時時間，單位秒
     * @return 是否獲取鎖成功
     */
    public boolean tryLock(String lockKey, String requestId, long expireTime) {
        ValueOperations<String, String> operations = redisTemplate.opsForValue();
        Boolean isLockSuccess = operations.setIfAbsent(lockKey, requestId, expireTime, TimeUnit.SECONDS);
        return Boolean.TRUE.equals(isLockSuccess);
    }
    /**
     * 釋放鎖。
     * @param lockKey 鎖的key
     * @param requestId 請求標識，需與加鎖時一致
     * @return 是否釋放鎖成功
     */
    public boolean releaseLock(String lockKey, String requestId) {
        String currentValue = redisTemplate.opsForValue().get(lockKey);
        if (requestId.equals(currentValue)) {
            redisTemplate.delete(lockKey);
            return true;
        }
        return false;
    }
    // 示例使用
    public void doSomethingUnderLock(String lockKey) {
        String requestId = UUID.randomUUID().toString(); // 生成唯一請求ID
        if (tryLock(lockKey, requestId, 5)) { // 嘗試獲取鎖，超時5秒
            try {
                // 執(zhí)行受保護的代碼邏輯
                System.out.println("執(zhí)行業(yè)務(wù)邏輯...");
            } finally {
                // 無論是否執(zhí)行成功都嘗試釋放鎖
                releaseLock(lockKey, requestId);
            }
        } else {
            System.out.println("獲取鎖失敗，操作被跳過。");
        }
    }
}