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项目中经常会用到计划任务,spring Boot 中通过@EnableScheduling启用计划任务,再通过@Scheduled注解配置计划任务如果运行。
@EnableScheduling
Application.java
启用计划任务, 在Spring Boot启动类加上注解@EnableScheduling,表示该项目启用计划任务
package api; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.ComponentScan; import org.springframework.data.jpa.repository.config.EnableJpaRepositories; import org.springframework.data.mongodb.repository.config.EnableMongoRepositories; import org.springframework.scheduling.annotation.EnableScheduling; import org.springframework.web.servlet.config.annotation.CorsRegistry; import org.springframework.web.servlet.config.annotation.WebMvcConfigurer; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; @SpringBootApplication @EnableAutoConfiguration @ComponentScan({ "api.config", "api.web", "api.rest", "api.service","api.schedule" }) @EnableMongoRepositories @EnableJpaRepositories @EnableScheduling public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } }
开启计划任务 @EnableScheduling
确保你的计划任务在 @ComponentScan 包中。
# 任务调度线程池大小 默认 1 建议根据任务加大 spring.task.scheduling.pool.size=1 # 调度线程名称前缀 默认 scheduling- spring.task.scheduling.thread-name-prefix=scheduling- # 线程池关闭时等待所有任务完成 spring.task.scheduling.shutdown.await-termination= # 调度线程关闭前最大等待时间,确保最后一定关闭 spring.task.scheduling.shutdown.await-termination-period=
在计划任务方法上加上@Scheduled注解,表示该方法是一个计划任务,项目启动后会去扫描该注解的方法并加入计划任务列表。
package api.schedule; import java.text.SimpleDateFormat; import java.util.Date; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Component; @Component public class ScheduledTasks { private static final Logger log = LoggerFactory.getLogger(ScheduledTasks.class); private static final SimpleDateFormat dateFormat = new SimpleDateFormat("HH:mm:ss"); public final static long ONE_DAY = 24 * 60 * 60 * 1000; public final static long ONE_HOUR = 60 * 60 * 1000; public ScheduledTasks() { // TODO Auto-generated constructor stub } @Scheduled(fixedRate = 5000) //5秒运行一次调度任务 public void echoCurrentTime() { log.info("The time is now {}", dateFormat.format(new Date())); } @Scheduled(fixedRate = ONE_DAY) public void scheduledTask() { System.out.println("每隔一天执行一次调度任务"); } @Scheduled(fixedDelay = ONE_HOUR) public void scheduleTask2() { System.out.println("运行完后隔一小时就执行任务"); } @Scheduled(initialDelay = 1000, fixedRate = 5000) public void doSomething() { // something that should execute periodically } @Scheduled(cron = "0 0/1 * * * ? ") public void ScheduledTask3() { System.out.println(" 每隔一分钟执行一次任务"); } }