在Spring Boot项目中，通过@EnableScheduling可启用Spring自带的定时任务支持，在通过@Scheduled注解定义定时任务，但是通过注解只能编写固定时间的定时任务，无法动态调整定时间隔，可通过实现SchedulingConfigurer接口实现动态定时任务注册。
参考代码：
package org.cent.demo.scanner.schedule;import lombok.AllArgsConstructor;import lombok.Data;import lombok.extern.slf4j.Slf4j;import org.springframework.context.annotation.Configuration;import org.springframework.scheduling.Trigger;import org.springframework.scheduling.annotation.EnableScheduling;import org.springframework.scheduling.annotation.SchedulingConfigurer;import org.springframework.scheduling.config.ScheduledTaskRegistrar;import org.springframework.scheduling.support.CronTrigger;import java.util.Arrays;import java.util.List;@Configuration@EnableScheduling@Slf4jpublic class DynamicSchedule implements SchedulingConfigurer {
private List tasks = Arrays.asList( new Task(1, "任务1", "*/30 * * * * *"), new Task(2, "任务2", "*/30 * * * * *"), new Task(3, "任务3", "*/30 * * * * *"), new Task(4, "任务4", "*/30 * * * * *"), new Task(5, "任务5", "*/30 * * * * *"), new Task(6, "任务6", "*/30 * * * * *"), new Task(7, "任务7", "*/30 * * * * *"), new Task(8, "任务8", "*/30 * * * * *"), new Task(9, "任务9", "*/30 * * * * *"), new Task(10, "任务10", "*/30 * * * * *")
); @Override
public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) {
tasks.forEach(task -> { //任务执行线程
Runnable runnable = () -> log.info("execute task {}", task.getId()); //任务触发器
Trigger trigger = triggerContext -> { //获取定时触发器，这里可以每次从数据库获取最新记录，更新触发器，实现定时间隔的动态调整
CronTrigger cronTrigger = new CronTrigger(task.getCron()); return cronTrigger.nextExecutionTime(triggerContext);
}; //注册任务
scheduledTaskRegistrar.addTriggerTask(runnable, trigger);
});
} @Data
@AllArgsConstructor
static class Task {
private int id;
private String name;
private String cron;
}
}
作者：centychen
链接：https://www.jianshu.com/p/546631cc2b8f
