在运行时重新安排Quartz

Question

在我的项目中,我们是Quartz用户的新手,编写我们的第一个Quartz任务.我们的任务正在运行,但显然我们想要了解如何管理它们.我们在Spring中配置它们就像这样:

<bean name="enoteExpirationTask"    class="org.springframework.scheduling.quartz.JobDetailBean">
    <property name="jobClass" value="gov.usdoj.afms.enote.job.DailyExpirationJob" />
    <property name="jobDataAsMap">
        <map>
            <entry key="messageService" value-ref="enoteMessageService" />
            <entry key="logicalDeleteAge" value="${expiryProcess.logical.age}" />
            <entry key="physicalDeleteAge" value="${expiryProcess.physical.age}" />
        </map>
    </property>
</bean>
<bean id="cronEnoteExpirationTaskTrigger" class="org.springframework.scheduling.quartz.CronTriggerBean">
    <property name="jobDetail" ref="enoteExpirationTask" />
    <property name="cronExpression" value="0 0 7 * * ?" />
</bean>

问题1:我可以让Quartz重新读取这个配置,这样如果我在运行时改变它,它会改变它的时间表吗？这将是最简单的解决方案,但我们没有看到任何内容.我希望我们错过了一些东西.

问题2:如果没有,我理解应该有第三方工具来做到这一点,Teracotta就是其中之一.是否有任何开源或免费软件实用程序可以让您非常简单地更改计划？

问题3:如果没有,编写一个小Java实用程序会涉及到什么？写一个是值得的吗？或者Teracotta是否有足够的增值值,你会建议买它？如果是这样,我可以向管理层出售的功能有何不同？

Answer 1

我的实现(Spring 3.0.6,Quartz 2.2.1):

public interface SchedulerService {

    void register( Class<? extends Job> jobClass, String cronExpression );

    void reschedule( Class<? extends Job> jobClass, String cronExpression );

}

@Service
public class SchedulerServiceImpl implements SchedulerService {

    private Scheduler scheduler;

    @PostConstruct
    void init() {
        try {
            scheduler = StdSchedulerFactory.getDefaultScheduler();
            scheduler.start();
        } catch ( Exception e ) {
            // handle exception
        }
    }

    @PreDestroy
    void destroy() {
        try {
            scheduler.shutdown();
        } catch ( Exception e ) {
            // handle exception
        }
    }

    @Override
    public void register( Class<? extends Job> jobClass, String cronExpression ) {
        try {
            String name = jobClass.getSimpleName();
            CronScheduleBuilder cronScheduleBuilder = CronScheduleBuilder.cronSchedule( cronExpression );

            JobDetail jobDetail = JobBuilder.newJob( jobClass ).withIdentity( name ).build();
            CronTrigger cronTrigger = TriggerBuilder.newTrigger().withIdentity( name ).withSchedule( cronScheduleBuilder ).build();

            scheduler.scheduleJob( jobDetail, cronTrigger );
        } catch ( Exception e ) {
            // handle exception
        }
    }

    @Override
    public void reschedule( Class<? extends Job> jobClass, String cronExpression ) {
        try {
            String name = jobClass.getSimpleName();
            CronScheduleBuilder cronScheduleBuilder = CronScheduleBuilder.cronSchedule( cronExpression );

            CronTrigger newCronTrigger = TriggerBuilder.newTrigger().withIdentity( name ).withSchedule( cronScheduleBuilder ).build();

            scheduler.rescheduleJob( TriggerKey.triggerKey( name ), newCronTrigger );
        } catch ( Exception e ) {
            // handle exception
        }
    }

}

使用示例:

@Service
public class MyServiceImpl implements MyService {

    @Autowired
    SchedulerService schedulerService;

    @PostConstruct
    void init() {
        schedulerService.register( MyJob.class, "0 10 * * * ?" );
    }

    @Override
    public void reschedule( String cronExpression ) {
        schedulerService.reschedule( MyJob.class, cronExpression );
    }

    @DisallowConcurrentExecution
    public static class MyJob implements Job {

        @Override
        public void execute( JobExecutionContext context ) throws JobExecutionException {
            // ...
        }

    }

}