public class RedisDistributedLock {
    private final RedisTemplate<String, String> redisTemplate;
    private final String lockKey;
    private final String lockValue; // 用于標識鎖持有者（支持可重入）
    private final long expireMillis; // 鎖過期時間（避免死鎖）
    // 構(gòu)造函數(shù)：初始化鎖參數(shù)
    public RedisDistributedLock(RedisTemplate<String, String> redisTemplate, 
                               String lockKey, String requestId, long expireMillis) {
        this.redisTemplate = redisTemplate;
        this.lockKey = lockKey;
        this.lockValue = requestId; // 建議使用UUID+線程ID
        this.expireMillis = expireMillis;
    }
    // 嘗試獲取鎖（原子操作）
    public boolean tryLock() {
        // 使用Redis的SET命令實現(xiàn)：NX（不存在則設(shè)置）+ PX（毫秒過期）
        return redisTemplate.opsForValue().setIfAbsent(lockKey, lockValue, expireMillis, TimeUnit.MILLISECONDS);
    }
    // 釋放鎖（需校驗持有者，避免誤釋放）
    public boolean unlock() {
        // 使用Lua腳本保證刪除操作的原子性
        String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
        Long result = (Long) redisTemplate.execute(
            new DefaultRedisScript<>(script, Long.class),
            Collections.singletonList(lockKey),
            lockValue
        );
        return result != null && result > 0;
    }
    // 帶超時等待的獲取鎖（輪詢重試）
    public boolean tryLock(long waitTime, TimeUnit unit) throws InterruptedException {
        long timeout = unit.toMillis(waitTime);
        long start = System.currentTimeMillis();
        while (true) {
            if (tryLock()) {
                return true;
            }
            // 等待重試（避免自旋過于頻繁）
            long remaining = timeout - (System.currentTimeMillis() - start);
            if (remaining <= 0) {
                return false; // 超時未獲取到鎖
            }
            Thread.sleep(Math.min(remaining, 100)); // 最多等待100ms重試
        }
    }
}

@XxlJob("shardingTask")
public ReturnT<String> shardingHandler(String param) {
    // 獲取分片參數(shù)（由調(diào)度中心分配）
    ShardingUtil.ShardingVO shardingVO = ShardingUtil.getShardingVo();
    int shardIndex = shardingVO.getIndex(); // 當前分片索引（0-4）
    int shardTotal = shardingVO.getTotal(); // 總分片數(shù)（5）
    // 按分片處理數(shù)據(jù)（如按ID取模：id % shardTotal == shardIndex）
    List<Data> dataList = dataService.queryBySharding(shardIndex, shardTotal);
    for (Data data : dataList) {
        processData(data);
    }
    return ReturnT.SUCCESS;
}

// 自定義任務(wù)執(zhí)行指標（使用Micrometer）
@Component
public class TaskMetrics {
    private final MeterRegistry meterRegistry;
    public TaskMetrics(MeterRegistry meterRegistry) {
        this.meterRegistry = meterRegistry;
    }
    // 記錄任務(wù)執(zhí)行耗時
    public void recordTaskDuration(String taskName, long durationMs) {
        Timer.builder("task.execution.duration")
             .tag("task", taskName)
             .register(meterRegistry)
             .record(durationMs, TimeUnit.MILLISECONDS);
    }
    // 記錄任務(wù)失敗次數(shù)
    public void incrementFailCount(String taskName) {
        Counter.builder("task.execution.fail")
               .tag("task", taskName)
               .register(meterRegistry)
               .increment();
    }
}

@XxlJob("orderTimeoutTask")
public ReturnT<String> orderTimeoutHandler(String param) {
    long start = System.currentTimeMillis();
    try {
        // 任務(wù)邏輯...
        metrics.recordTaskDuration("orderTimeoutTask", System.currentTimeMillis() - start);
        return ReturnT.SUCCESS;
    } catch (Exception e) {
        metrics.incrementFailCount("orderTimeoutTask");
        return ReturnT.FAIL;
    }
}

// 釘釘告警示例
public class DingTalkAlarm {
    private final String webhook;
    public void sendAlarm(String message) {
        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.APPLICATION_JSON);
        Map<String, Object> body = new HashMap<>();
        body.put("msgtype", "text");
        body.put("text", Map.of("content", "定時任務(wù)告警：" + message));
        new RestTemplate().postForObject(webhook, new HttpEntity<>(body, headers), String.class);
    }
}

@Component
public class RedisScheduledTask {
    @Autowired
    private RedisTemplate<String, String> redisTemplate;
    @Autowired
    private TaskService taskService;
    // 初始化定時任務(wù)（每分鐘執(zhí)行一次）
    @PostConstruct
    public void init() {
        ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();
        executor.scheduleAtFixedRate(this::executeTask, 0, 1, TimeUnit.MINUTES);
    }
    // 執(zhí)行任務(wù)（加分布式鎖）
    private void executeTask() {
        String lockKey = "task:order:timeout";
        String requestId = UUID.randomUUID().toString();
        RedisDistributedLock lock = new RedisDistributedLock(redisTemplate, lockKey, requestId, 60000);
        try {
            if (lock.tryLock()) {
                // 執(zhí)行核心邏輯
                taskService.processTimeoutOrders();
            } else {
                log.info("任務(wù)被其他節(jié)點執(zhí)行，當前節(jié)點跳過");
            }
        } finally {
            lock.unlock(); // 釋放鎖
        }
    }
}