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。
核心代码:
@Component public class ScheduleTask { private Logger logger = LoggerFactory.getLogger(ScheduleTask.class); @Scheduled(cron = "0/1 * * * * ? ") public void one() { logger.info("one:" + new Date()); } @Scheduled(cron = "0/1 * * * * ? ") public void two() { logger.info("two:" + new Date()); } @Scheduled(cron = "0/1 * * * * ? ") 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-8") @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(Executors.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 = "0/1 * * * * ? ") @Async public void one() { logger.info("one Async:" + new Date()); } @Scheduled(cron = "0/1 * * * * ? ") @Async public void two() { logger.info("two Async:" + new Date()); } @Scheduled(cron = "0/1 * * * * ? ") @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 1") public String getCron(); } /** * 执行定时任务. */ public void configureTasks(ScheduledTaskRegistrar taskRegistrar) { taskRegistrar.addTriggerTask( //1.添加任务内容(Runnable) () -> System.out.println("执行动态定时任务: " + LocalDateTime.now().toLocalTime()), //2.设置执行周期(Trigger) triggerContext -> { //2.1 从数据库获取执行周期 String cron = cronMapper.getCron(); //2.2 合法性校验. if (StringUtils.isEmpty(cron)) { // Omitted Code .. } //2.3 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:mysql://127.0.0.1:3306/test username: root password: 1234
SQL脚本:
DROP DATABASE IF EXISTS `test`; CREATE DATABASE `test`; USE `test`; DROP TABLE IF EXISTS `cron`; CREATE TABLE `cron` ( `cron_id` varchar(30) NOT NULL PRIMARY KEY, `cron` varchar(30) NOT NULL ); INSERT INTO `cron` VALUES ('1', '0/5 * * * * ?');
运行效果如下:
<!--引入quartz定时框架--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-quartz</artifactId> </dependency>
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: 10000 useProperties: false threadPool: class: org.quartz.simpl.SimpleThreadPool threadCount: 10 threadPriority: 5 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://127.0.0.1:3306/test username: root password: 1234
@SpringBootApplication @EnableScheduling public class BlogQuartzApplication { public static void main(String[] args) { SpringApplication.run(BlogQuartzApplication.class, args); } }
@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("0/1 * * * * ?"); return TriggerBuilder.newTrigger() .forJob(myCronJobDetail()) .withIdentity("CouponTimeOutJobTrigger") .withSchedule(cronScheduleBuilder) .build(); } }
public class CouponTimeOutJob extends QuartzJobBean { @Override protected void executeInternal(JobExecutionContext jobExecutionContext) throws JobExecutionException { System.out.println("定时任务执行"); } }
(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
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
<dependency> <groupId>com.xuxueli</groupId> <artifactId>xxl-job-core</artifactId> <version>2.2.0</version> </dependency>
@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; } }
# web port server.port=8081 # no web #spring.main.web-environment=false ### xxl-job admin address list, such as "http://address" or "http://address01,http://address02" xxl.job.admin.addresses=http://127.0.0.1:8080/xxl-job-admin ### 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=8888 ### xxl-job executor log-path xxl.job.executor.logpath=/data/applogs/xxl-job/jobhandler ### xxl-job executor log-retention-days xxl.job.executor.logretentiondays=30
@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 = 0; i < 5; i++) { XxlJobLogger.log("beat at:" + i); TimeUnit.SECONDS.sleep(2); } return ReturnT.SUCCESS; } }
分别如下所示:
<!-- 分布式定时任务锁 --> <!-- https://mvnrepository.com/artifact/net.javacrumbs.shedlock/shedlock-spring --> <dependency> <groupId>net.javacrumbs.shedlock</groupId> <artifactId>shedlock-spring</artifactId> <version>4.0.4</version> </dependency> <!-- 使用redis做分布式任务 --> <dependency> <groupId>net.javacrumbs.shedlock</groupId> <artifactId>shedlock-provider-redis-spring</artifactId> <version>2.5.0</version> </dependency> <!-- redis组件 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency>
@Configuration @EnableSchedulerLock(defaultLockAtMostFor = "PT30M") public class ShedLockConfig { @Bean public LockProvider lockProvider(RedisTemplate redisTemplate) { return new RedisLockProvider(redisTemplate.getConnectionFactory()); } }
@Component public class TaskSchedule { /** * 每分钟执行一次 * [秒] [分] [小时] [日] [月] [周] [年] */ @Scheduled(cron = "1 * * * * ?") @SchedulerLock(name = "synchronousSchedule") public void SynchronousSchedule() { System.out.println("Start run schedule to synchronous data:" + new Date()); } }
@SpringBootApplication @EnableScheduling public class ShedLockRedisApplication { public static void main(String[] args) { SpringApplication.run(ShedLockRedisApplication.class); } }
server: tomcat: uri-encoding: UTF-8 max-threads: 1000 min-spare-threads: 30 port: 8083 spring: redis: database: 0 host: localhost port: 6379 password: # 密码(默认为空) timeout: 6000ms # 连接超时时长(毫秒) jedis: pool: max-active: 1000 # 连接池最大连接数(使用负值表示没有限制) max-wait: -1ms # 连接池最大阻塞等待时间(使用负值表示没有限制) max-idle: 10 # 连接池中的最大空闲连接 min-idle: 5 # 连接池中的最小空闲连接
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:
本次代码例子已放至我的GitHub:https://github.com/developers-youcong/blog-job
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