springboot实现多实例crontab抢占定时任务(实例代码)

<dependency>
   <groupId>org.redisson</groupId>
   <artifactId>redisson</artifactId>
   <version>3.12.0</version>
</dependency>

package com.brand.log.scheduler;
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.SchedulingConfigurer;
import org.springframework.scheduling.config.ScheduledTaskRegistrar;
import java.util.concurrent.Executors;
@Configuration
public class Kernel implements SchedulingConfigurer {
 @Override
 public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
  //设定一个长度10的定时任务线程池
  taskRegistrar.setScheduler(Executors.newScheduledThreadPool(4));
 }
}

package com.brand.log.util;
import lombok.extern.slf4j.Slf4j;
import org.redisson.Redisson;
import org.redisson.config.Config;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
@Component
@Slf4j
public class RedissonManager {
 @Value("${spring.redis.host}")
 private String host;
 @Value("${spring.redis.port}")
 private int port;
 private Redisson redisson = null;
 private Config config = new Config();
 @PostConstruct
 private void init() {
  try {
   config.useSingleServer().setAddress("redis://" + host + ":" + port);
   log.info("redisson address {} {}", host, port);
   redisson = (Redisson) Redisson.create(config);
   log.info("Redisson 初始化完成");
  }
  catch (Exception e) {
   log.error("init Redisson error ", e);
  }
 }
 public Redisson getRedisson() {
  return redisson;
 }
}

package com.brand.log.scheduler;
import com.brand.log.util.DateFormatV1;
import com.brand.log.util.RedisUtil;
import com.brand.log.util.RedissonManager;
import lombok.extern.slf4j.Slf4j;
import org.redisson.Redisson;
import org.redisson.api.RLock;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import java.util.concurrent.TimeUnit;
@Component
@Slf4j
public class CronSynData {
 @Autowired
 RedissonManager redissonManager;
 @Autowired
 RedisUtil redisUtil;
 @Autowired
 DateFormatV1 dateFormatV1;
 private String lokFlag = ".handleKernel";
 private Redisson redisson = null;
 /*
 * java定时脚本挂靠实例
 * 多实例会有重复调用问题 + 使用Redisson实现分布式锁
 * 业务逻辑必须加锁 + 且需要保证 tryLock 等待时间小于cron的最小间隔执行时间
 * */
 @Scheduled(cron = "*/10 * * * * *")
 public void handleKernel() {
  redisson = redissonManager.getRedisson();
  if (redisson != null) {
   RLock lock = redisson.getLock(this.getClass().getName() + lokFlag);
   Boolean stat = false;
   try {
    // 尝试加锁，立即返回，最多等待5s自动解锁
    stat = lock.tryLock(0, 5, TimeUnit.SECONDS);
    if (stat) {
     log.info("{} 取锁成功！{}",this.getClass().getName(), Thread.currentThread().getName());
     redisUtil.checkCount("log:limit_", dateFormatV1.getDate("HH", "GMT+8"), 60*10, 1000);
    } else {
     log.info("{}没有获取到锁:{}", this.getClass().getName(), Thread.currentThread().getName());
    }
   } catch (InterruptedException e) {
    log.error("Redisson 获取分布式锁异常", e);
    if (!stat){
     return;
    }
    lock.unlock();
   }
  }
 }
}