1.使用zookeeper做分布式锁

@Component
public class MutexConfig {

	@Value(value = "${zookeeper.host}")
	private String zkHost;

	public Boolean getLock(String lock, Integer acquireTime, Integer sleepTime) throws Exception {
		RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3);
		CuratorFramework client = CuratorFrameworkFactory.newClient(zkHost, retryPolicy);
		client.start();
		InterProcessMutex mutex = new InterProcessMutex(client, lock);
		Boolean result = mutex.acquire(acquireTime, TimeUnit.MILLISECONDS);
		Thread.sleep(sleepTime);
		if (mutex.isAcquiredInThisProcess()) {
			mutex.release();
		}
		client.close();
		return result;
	}
}

在配置文件里配置

zookeeper.path.smsxxx.xxtemplate=/dmp/smsxxx/xxtemplate

在定时任务实现类编写定时任务

@Value(value = "${zookeeper.path.smsxxx.xxtemplate}")
	private String jd;


/**
	 * 定时更新短信模板状态
	 */
	@Scheduled(cron = "0 0/10 * * * ?")
	public void updateJdState() {
		try {
			logger.info("updateJdState start");
			Boolean result = mutexConfig.getLock(jd, 2000, 3000);
			if (Boolean.TRUE.equals(result)) {
				logger.info("updateJdState content start");
				smsTemplateService.updateJdState();
			}
			logger.info("end");
		} catch (Exception e) {
			logger.error("updateJdState error: {}", e.getMessage());
		}
	}

2.使用mongodb做分布式锁

编写dao类

public interface DistributeLockerDAO extends BaseDAO<LockerPO> {

    /**
     * insert one locker
     * @param lockerPo
     * @return true if success, false if the locker is duplicated
     */
    boolean insert(LockerPO lockerPo);

    /**
     * the acquirer remove the locker with the id
     * @param id
     * @param acquirer
     * @return
     */
    boolean remove(String id, String acquirer);

    /**
     * update locker's time held by the acquirer
     * @param id
     * @param acquirer
     * @param time
     * @return
     */
    boolean updateShakenTime(String id, String acquirer, LocalDateTime time);

    /**
     * get the locker by the locker id
     * @param lockerId
     * @return
     */
    Optional<LockerPO> getLocker(String lockerId);

    /**
     * list the lockers
     * @param offset
     * @param limit
     * @return
     */
    List<LockerPO> list(long offset, int limit);


    /**
     * list the lockers with the acquirer
     * @param offset
     * @param limit
     * @param acquirer
     * @return
     */
    List<LockerPO> list(String acquirer, long offset, int limit);

    @Data
    @Accessors(chain = true)
    class LockerCountOfAcquirer {
        @Field("_id")
        String acquirer;
        long count;
    }
    /**
     * list the locker count group by the user
     * @return the map user->count pair list
     */
    List<LockerCountOfAcquirer> countByAcquirer();
}

锁的实体类

@Document(CollectionName.LOCKER)
@Data
@Accessors(chain = true)
public class LockerPO implements IdPO {
    @Id
    private String id;
    private String acquirer;
    private LocalDateTime acquiredAt;
    private LocalDateTime shakenAt;
}

锁的服务类

@Service
public class DistributeLockerServiceImpl implements DistributeLockerService {

    private final DistributeLockerDAO distributeLockerDAO;
    private final Gauge gauge;
    private final List<String> lastSyncAcquires;

    public DistributeLockerServiceImpl(
        @Value(value = "${prometheus.namespace}") String namespace,
        @Value(value = "${prometheus.subsystem}") String subsystem,
        DistributeLockerDAO distributeLockerDAO,
        MeterRegistry registry
    ) {
        this.distributeLockerDAO = distributeLockerDAO;
        lastSyncAcquires = new ArrayList<>();
        gauge = Gauge.build()
            .namespace(namespace)
            .subsystem(subsystem)
            .name("distribute_locker_total")
            .labelNames("user")
            .help("distribute locker statistic by the acquirer")
            .register(((PrometheusMeterRegistry)registry).getPrometheusRegistry());
    }

    @Override
    public boolean tryLock(String lockerId, String user) {

        LocalDateTime dateTime = LocalDateTime.now();
        boolean suc = distributeLockerDAO.insert(
            new LockerPO().setId(lockerId)
                .setAcquirer(user)
                .setAcquiredAt(dateTime)
                .setShakenAt(dateTime));

        if (!suc) {
            suc = distributeLockerDAO.updateShakenTime(lockerId, user, dateTime);
        }

        return suc;
    }

    @Override
    public boolean release(String lockerId, String user) {

        return distributeLockerDAO.remove(lockerId, user);
    }

    @Override
    public boolean shake(String lockerId, String user) {

        return distributeLockerDAO.updateShakenTime(lockerId, user, LocalDateTime.now());
    }

    @Override
    public Optional<LockerPO> getLocker(String lockerId) {

        return distributeLockerDAO.getLocker(lockerId);
    }

    @Override
    public List<LockerPO> list(long offset, int limit) {

        return distributeLockerDAO.list(offset, limit);
    }

    @Override public List<LockerPO> list(String user, long offset, int limit) {
        return distributeLockerDAO.list(user, offset, limit);
    }

    @Scheduled(fixedDelay = 500)
    public void monitorLockerCountOfAcquirer() {

        List<DistributeLockerDAO.LockerCountOfAcquirer> lockerCountOfAcquirers = distributeLockerDAO.countByAcquirer();
        updateMonitorOfLockerCountOfAcquirer(lockerCountOfAcquirers);

        List<String> acquires = lockerCountOfAcquirers.stream()
            .map(DistributeLockerDAO.LockerCountOfAcquirer::getAcquirer)
            .collect(Collectors.toList());

        resetLockerCountOfDeletedAcquire(acquires);
        updateLastSyncAcquires(acquires);
    }

    private void updateMonitorOfLockerCountOfAcquirer(List<DistributeLockerDAO.LockerCountOfAcquirer> lockerCountOfAcquirers) {
        lockerCountOfAcquirers.forEach(c -> gauge.labels(c.getAcquirer()).set(c.getCount()));
    }

    private void resetLockerCountOfDeletedAcquire(List<String> countOfUsers) {
        calcDeletedAcquirers(countOfUsers).forEach(a -> gauge.labels(a).set(0));
    }

    private List<String> calcDeletedAcquirers(List<String> acquirers) {
        return lastSyncAcquires.stream()
            .filter(s -> !acquirers.contains(s))
            .collect(Collectors.toList());
    }

    private void updateLastSyncAcquires(List<String> acquirers) {
        lastSyncAcquires.clear();
        lastSyncAcquires.addAll(acquirers);
    }
}

分布式锁的基类

@Slf4j
public class DistributeLockerBase implements LockerShakerScheduler {

    private final String acquirer;
    private final List<String> lockingIds;
    private final DistributeLockerService distributeLockerService;

    protected DistributeLockerBase(String acquirer,
        DistributeLockerService distributeLockerService) {

        Preconditions.checkArgument(!Strings.isNullOrEmpty(acquirer));
        Preconditions.checkArgument(distributeLockerService != null);

        this.acquirer = acquirer;
        this.lockingIds = Collections.synchronizedList(new ArrayList<>());
        this.distributeLockerService = distributeLockerService;
    }

    public final String getAcquirer() {
        return acquirer;
    }

    protected boolean lock(String lockerId) {

        boolean suc = distributeLockerService.tryLock(lockerId, acquirer);
        if (suc) {
            lockingIds.add(lockerId);
        }
        log.info("lock [{}], [{}]", lockerId, suc);
        return suc;
    }

    protected boolean release(String lockerId) {
        boolean suc = distributeLockerService.release(lockerId, acquirer);
        lockingIds.remove(lockerId);
        log.info("release [{}], [{}]", lockerId, suc);
        return suc;
    }

    /**
     * delay 1 second. after sync finished
     */
    @Scheduled(fixedDelay = 1000)
    @Override
    public void shake() {

        List<String> lockingIdsCopied;
        synchronized (this.lockingIds) {
            lockingIdsCopied = new ArrayList<>(this.lockingIds);
        }

        lockingIdsCopied.forEach(id -> {
            if (!distributeLockerService.shake(id, acquirer)) {
                log.error("[{}] shakes [{}] FAILED", acquirer, id);
            } else {
                log.info("[{}] shakes [{}] SUCCESS", acquirer, id);
            }
        });
    }
}


/**
 * the class used for defining the shake method
 * so that the <code>shake</code> method in the <code>DistributeLockerBase</code> can auto-scheduled
 * when some class inherits <code>DistributeLockerBase</code> and marks as a bean
 *
 * NOTE: it's dependent on the Spring boot version
 */
interface LockerShakerScheduler {
    void shake();
}

实现定时任务类

@Slf4j
@Component
public class BrandUVSyncher extends DistributeLockerBase {

     private static final String SPLITTER = "+";
    private static final String TASK_ID_PREFIX = "lbi-openapi-brandUV:";
    private static final long PERIOD = 10_000;

    private final MidPlatformClient midPlatformClient;
    private final BrandUVDAO brandUVDAO;
    private final AreaDAO areaDAO;
    private final List<AreaPO> top2LevelCities;
    /**
     * geo of banks in some city
     * cityName -> {bankName -> coordinate}
     */
    private final Map<String, Map<String, List<double[]>>> geoOfBanks;

    BrandUVSyncher(MidPlatformClient midPlatformClient, BrandUVDAO brandUVDAO,
        DistributeLockerService distributeLockerService, AreaDAO areaDAO) {
        super("BrandUVSyncher:" + UuidGenerator.newBase64Uuid(), distributeLockerService);
        this.midPlatformClient = midPlatformClient;
        this.brandUVDAO = brandUVDAO;
        this.areaDAO = areaDAO;
        this.geoOfBanks = loadGeoOfBanks();
        this.top2LevelCities = loadTop2LevelCity();
    }


      /**
     * sync the living&working uv of the cities of level 1&2
     */
    @Scheduled(fixedDelay = PERIOD, initialDelay = 3000)
    public void syncCityLivingAndWorkingUV() {

        log.info("run sync city WORKING&LIVING UV");

        // DO NOT MODIFY ME!
        final String lockerID = buildLockerID("syncCityLivingAndWorkingUV");

        LocalDate now = LocalDate.now();
        if (!isTimeToSync(now)) {
            return;
        }

        if (!lock(lockerID)) {
            log.error("locker [{}] failed", lockerID);
            return;
        }

        if (top2LevelCities.isEmpty()) {
            log.info("empty level 1 and level 2 cities");
            return;
        }

        LocalDate preMonth = now.minusMonths(1);
        LocalDate month = LocalDate.of(preMonth.getYear(), preMonth.getMonth(), 1);

        try {
            Stream.of(Brand.values()).forEach(
                b -> syncCityLivingAndWorkingUV(b.getCode(), month, top2LevelCities)
            );
        } finally {
            release(lockerID);
        }
    }


}

 

3.使用shedlock实现分布式定时任务锁

https://www.jianshu.com/p/941416645606

 

 

 

 

 

 

Logo

权威|前沿|技术|干货|国内首个API全生命周期开发者社区

更多推荐