定时任务应用非常广泛， Java 提供的现有解决方案有很多。

本次主要讲schedule、quartz、xxl-job、shedlock等相关的代码实践。

一、SpringBoot使用Schedule

核心代码:

 @Component
public class ScheduleTask {

    private Logger logger = LoggerFactory.getLogger(ScheduleTask.class);

    @Scheduled(cron = "/1 * * * * ? ")
    public void one() {

        logger.info("one:" + new Date());
    }

    @Scheduled(cron = "/1 * * * * ? ")
    public void two() {

        logger.info("two:" + new Date());
    }


    @Scheduled(cron = "/1 * * * * ? ")
    public void three() {

        logger.info("three:" + new Date());
    }
}

运行效果如下:

除此之外还可以这样实现，核心代码:

 @PropertySource(value = {
        "classpath:task.properties",
}, encoding = "utf-")
@Component("scheduleTask")
public class ScheduleTask implements SchedulingConfigurer {


    @Value("${TEST_JOB_TASK_CRON}")
    private String cron;

    @Override
    public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {

        scheduledTaskRegistrar.addTriggerTask(new Runnable() {

            @Override
            public void run() {
                System.out.println("执行任务:" + DateUtil.date());


            }

        }, new Trigger() {
            @Override
            public Date nextExecutionTime(TriggerContext triggerContext) {
                return new CronTrigger(cron).nextExecutionTime(triggerContext);
            }
        });
    }

    public void setCron(String cron) {
        this.cron = cron;
    }
}

有朋友或许很疑惑，为什么要写这么一大堆，这个与前面的代码又有何区别呢？

区别是多线程并行。其实多线程并行也可以不用这么写，只需写一段核心配置类代码即可。

定时任务多线程配置类:

 @Configuration
public class ScheduleConfig implements SchedulingConfigurer {

    public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {
        scheduledTaskRegistrar.setScheduler( executor s.newScheduledThreadPool(5));
    }
}

再次启动，查看效果，如下:

由此看出走不同的线程执行，不同的线程执行的好处是，如果某一个线程挂掉后，并不会阻塞导致其它定时任务无法执行。

另外如果要想并发执行，前面的配置可以不要，直接用SpringBoot提供的现成注解即可，核心代码如下:

 @Component
@EnableAsync
public class ScheduleAsyncTask {

    private Logger logger = LoggerFactory.getLogger(ScheduleAsyncTask.class);

    @Scheduled(cron = "/1 * * * * ? ")
    @Async
    public void one() {

        logger.info("one Async:" + new Date());
    }

    @Scheduled(cron = "/1 * * * * ? ")
    @Async
    public void two() {

        logger.info("two Async:" + new Date());
    }


    @Scheduled(cron = "/1 * * * * ? ")
    @Async
    public void three() {

        logger.info("three Async:" + new Date());
    }
}

除此外，还有基于schedule动态定时任务(所谓动态只不过是指cron表达式放在对应的数据表里)，简单示例代码:

 @Configuration
public class DynamicScheduleTask implements SchedulingConfigurer {

    @Autowired
    @SuppressWarnings("all")
    CronMapper cronMapper;

    @Mapper
    public interface CronMapper {
        @Select("select cron from cron limit")
        public String getCron();
    }

    /**
     * 执行定时任务.
     */    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {

        taskRegistrar.addTriggerTask(
                //.添加任务内容(Runnable)
                () -> System.out.println("执行动态定时任务: " + LocalDateTime.now().toLocalTime()),
                //.设置执行周期(Trigger)
                triggerContext -> {
                    //.1 从数据库获取执行周期
                    String cron = cronMapper.getCron();
                    //.2 合法性校验.
                    if (StringUtils.isEmpty(cron)) {
                        // Omitted Code ..
                    }
                    //.3 返回执行周期(Date)
                    return new CronTrigger(cron).nextExecutionTime(triggerContext);
                }
        );
    }



}

核心配置文件(application.yml):

 spring:
  datasource:
    url: jdbc:my SQL ://127.0.0.1:3306/test
     username : root
    password:

SQL脚本:

 DROP DATABASE IF EXISTS `test`;
CREATE DATABASE `test`;
USE `test`;
DROP TABLE IF EXISTS `cron`;
CREATE TABLE `cron`  (
  `cron_id` varchar() NOT NULL PRIMARY KEY,
  `cron` varchar() NOT NULL  
);
INSERT INTO `cron` VALUES ('', '0/5 * * * * ?');

运行效果如下:

二、SpringBoot使用Quartz

1. Maven 依赖

 <!--引入quartz定时框架-->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-quartz</artifactId>
</dependency>

2.配置文件

 spring:
  quartz:
    #相关属性配置
    properties:
      org:
        quartz:
          scheduler:
            instanceName: clusteredScheduler
            instanceId: AUTO
          jobStore:
            class: org.quartz.impl.jdbcjobstore.JobStoreTX
            driverDelegateClass: org.quartz.impl.jdbcjobstore.StdJDBCDelegate
            tablePrefix: QRTZ_
            isClustered: true
            clusterCheckinInterval:
            useProperties: false
          threadPool:
            class: org.quartz.simpl.SimpleThreadPool
            threadCount:
            threadPriority:
            threadsInheritContextClassLoaderOfInitializingThread: true
    #数据库方式
    job-store-type: jdbc
    #初始化表结构
    jdbc:
      initialize-schema: always
  datasource:
    url: jdbc:mysql://.0.0.1:3306/test
    username: root
    password:

3.启动类

 @SpringBootApplication
@EnableScheduling
public class BlogQuartzApplication {

    public static void main(String[] args) {
        SpringApplication.run(BlogQuartzApplication.class, args);
    }


}

4.配置类

 @Configuration
public class QuartzConfiguration {
    // 使用jobDetail包装job
    @Bean
    public JobDetail myCronJobDetail() {
        return JobBuilder.newJob(CouponTimeOutJob.class).withIdentity("couponTimeOutJob").storeDurably().build();
    }

    // 把jobDetail注册到Cron表达式的trigger上去
    @Bean
    public Trigger CronJobTrigger() {
        CronScheduleBuilder cronScheduleBuilder = CronScheduleBuilder.cronSchedule("/1 * * * * ?");

        return TriggerBuilder.newTrigger()
                .forJob(myCronJobDetail())
                .withIdentity("CouponTimeOutJobTrigger")
                .withSchedule(cronScheduleBuilder)
                .build();
    }
}

5.定时任务类

 public class CouponTimeOutJob extends QuartzJobBean {
    @Override
    protected void executeInternal(JobExecutionContext jobExecutionContext) throws JobExecutionException {
        System.out.println("定时任务执行");
    }
}

6.启动成功不报错

(1)对应的数据库会生成定时任务相关的数据表

(2)控制台不断输出定时任务执行日志

三、SpringBoot使用xxl-job

之前写过一样的例子，如今简化了下。

关于xxl-job使用详情，可以参考我的这篇文章:

SpringBoot整合Xxl-Job

1.Maven依赖

 <dependency>
    <groupId>com.xuxueli</groupId>
    <artifactId>xxl-job-core</artifactId>
    <version>.2.0</version>
</dependency>

2.配置类

 @Configuration
public class XxlJobConfig {
    private Logger logger = LoggerFactory.getLogger(XxlJobConfig.class);

    @Value("${xxl.job.admin.addresses}")
    private String adminAddresses;

    @Value("${xxl.job.executor.appname}")
    private String appName;

    @Value("${xxl.job.executor.ip}")
    private String ip;

    @Value("${xxl.job.executor.port}")
    private int port;

    @Value("${xxl.job.accessToken}")
    private String accessToken;

    @Value("${xxl.job.executor.logpath}")
    private String logPath;

    @Value("${xxl.job.executor.logretentiondays}")
    private int logRetentionDays;


    @Bean(initMethod = "start", destroyMethod = "destroy")
    public XxlJobSpringExecutor xxlJobExecutor() {
        logger.info(">>>>>>>>>>> xxl-job config init.");
        XxlJobSpringExecutor xxlJobSpringExecutor = new XxlJobSpringExecutor();
        xxlJobSpringExecutor.setAdminAddresses(adminAddresses);
        xxlJobSpringExecutor.setAppname(appName);
        xxlJobSpringExecutor.setIp(ip);
        xxlJobSpringExecutor.setPort(port);
        xxlJobSpringExecutor.setAccessToken(accessToken);
        xxlJobSpringExecutor.setLogPath(logPath);
        xxlJobSpringExecutor.setLogRetentionDays(logRetentionDays);

        return xxlJobSpringExecutor;
    }

}

3.配置文件内容

 # web port
server.port=
# no web
#spring.main.web-environment=false
### xxl-job admin address list, such as "#; or "#34;
xxl.job.admin.addresses=
### xxl-job, access token
xxl.job.accessToken=
### xxl-job executor appname
xxl.job.executor.appname=blog-job-xxl-job
### xxl-job executor registry-address: default use address to registry , otherwise use ip:port if address is null
xxl.job.executor.address=
### xxl-job executor server-info
xxl.job.executor.ip=
xxl.job.executor.port=
### xxl-job executor log-path
xxl.job.executor.logpath=/data/applogs/xxl-job/jobhandler
### xxl-job executor log-retention-days
xxl.job.executor.logretentiondays=

4.定时任务类

 @Component
public class XxlJobTaskExample {


    @XxlJob("blogJobHandler")
    public ReturnT<String> blogJobHandler(String param) throws Exception {
        System.out.println("执行");
        XxlJobLogger.log("XXL-JOB, Hello World.");

        for (int i =; i < 5; i++) {
            XxlJobLogger.log("beat at:" + i);
            TimeUnit.SECONDS.sleep();
        }
        return ReturnT.SUCCESS;
    }

}

5.执行效果

分别如下所示:

四、SpringBoot使用ShedLock

1.导入Maven依赖

 <!-- 分布式定时任务锁 -->
   <!--  -->
   <dependency>
       <groupId>net.javacrumbs.shedlock</groupId>
       <artifactId>shedlock-spring</artifactId>
       <version>.0.4</version>
   </dependency>
   <!-- 使用redis做分布式任务 -->
   <dependency>
       <groupId>net.javacrumbs.shedlock</groupId>
       <artifactId>shedlock-provider-redis-spring</artifactId>
       <version>.5.0</version>
   </dependency>
   <!-- redis组件 -->
   <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-data-redis</artifactId>
   </dependency>

2.编写配置类

 @Configuration
@EnableSchedulerLock(defaultLockAtMostFor = "PTM")
public class ShedLockConfig {

    @Bean
    public LockProvider lockProvider(RedisTemplate redisTemplate) {
        return new RedisLockProvider(redisTemplate.getConnectionFactory());

    }

}

3.编写具体的定时任务

 @Component
public class TaskSchedule {

    /**
     * 每分钟执行一次
     * [秒] [分] [小时] [日] [月] [周] [年]
     */    @Scheduled(cron = " * * * * ?")
    @SchedulerLock(name = "synchronousSchedule")
    public void SynchronousSchedule() {

        System.out.println("Start run schedule to synchronous data:" + new Date());

    }
}

4.编写启动类

 @SpringBootApplication
@EnableScheduling
public class ShedLockRedisApplication {
    public static void main(String[] args) {
        SpringApplication.run(ShedLockRedisApplication.class);
    }
}

5.配置文件

 server:
  tomcat:
    uri-encoding: UTF-
    max-threads:
    min-spare-threads:
  port:

spring:
  redis:
    database:
    host: localhost
    port:
    password:      # 密码（默认为空）
    timeout:ms  # 连接超时时长（毫秒）
    jedis:
      pool:
        max-active:  #  连接池 最大连接数（使用负值表示没有限制）
        max-wait: -ms      # 连接池最大阻塞等待时间（使用负值表示没有限制）
        max-idle:      # 连接池中的最大空闲连接
        min-idle:       # 连接池中的最小空闲连接

6.测试

我之所以用shedlock是因为确保在集群环境下各微服务的定时任务只执行一个，而不是全部都运行相同的定时任务。

本次测试效果如下: