下次调用之前中断Spring Scheduler任务

Z时代
2024-01-10
分类：问答

我有一个Spring-Boot应用程序，它将成为我们要触发的其他几个流程的编排服务。我目前使用Spring

Scheduling设置它，以动态地从数据库中提取cron。我使用了rest方法来触发从数据库中提取新的cron信息的过程。此逻辑全部正常工作。唯一的“问题”是，它直到下一个计划运行才使用真正的问题才使用新的cron信息。

这是供参考的应用程序：

package com.bts.poc;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.Trigger;
import org.springframework.scheduling.TriggerContext;
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 org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import java.util.Date;
@SpringBootApplication
@EnableScheduling
@RestController
@RequestMapping("/APSCommon/Scheduling")
public class Application implements SchedulingConfigurer {
    @Autowired
    private DynamicCron dynamicCron;
    @Autowired
    PropertyManager propertyManager;
    public static void main(String[] args) throws Exception {
        SpringApplication.run(Application.class);
    }
    private String cronConfig() {
        String cronTabExpression = propertyManager.getProperty("COMPANY", "JOB_NAME","CRON_EXPRESSION");
        return cronTabExpression;
    }
    @Override
    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
        taskRegistrar.addTriggerTask(new Runnable() {
            @Override
            public void run() {
                dynamicCron.runJob();
            }
        }, new Trigger() {
            @Override
            public Date nextExecutionTime(TriggerContext triggerContext) {
                String cron = cronConfig();
                CronTrigger trigger = new CronTrigger(cron);
                Date nextExec = trigger.nextExecutionTime(triggerContext);
                DynamicCron.cronExpression = cron;
                return nextExec;
            }
        });
    }
    @RequestMapping(value = "/reloadScheduling", method = RequestMethod.GET)
    public String reloadScheduling() {
        PropertyManager.setResetProperties(true);
        return "schedules will be altered next run";
    }
}

回答：

因此，使用SchedulingConfigurer->

configureTasks时，您无法访问我正在使用的Spring版本（4.2.7.RELEASE）中的ScheduledFuture。从我读过的几篇文章中，已经提到它是将来可能的功能。我通过执行以下操作解决了这个问题：

package com.bts.poc;
import com.bts.poc.service.DynamicCron;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.MessageSourceAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.web.SpringBootServletInitializer;
import org.springframework.context.annotation.Bean;
import org.springframework.scheduling.TaskScheduler;
import org.springframework.scheduling.annotation.EnableScheduling;
import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
import org.springframework.scheduling.support.CronTrigger;
import org.springframework.web.bind.annotation.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.ArrayList;
import java.util.List;
import java.util.TimeZone;
import java.util.concurrent.ScheduledFuture;
@SpringBootApplication(exclude = MessageSourceAutoConfiguration.class)
@EnableScheduling
@RestController
public class Application extends SpringBootServletInitializer {
    @Autowired
    private DynamicCron dynamicCron;
    @Autowired
    private PropertyManager propertyManager;
    private static List<ScheduledFuture> scheduledFutures = new ArrayList<>();
    private static final Logger LOGGER = LoggerFactory.getLogger(Application.class);
    private static TaskScheduler scheduler;
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }
    private String cronConfig() {
        return propertyManager.getProperty("COMPANY", "JOB_NAME", "CRON_EXPRESSION");
    }
    @RequestMapping(value = {"scheduling/start"}, method = RequestMethod.GET)
    public @ResponseBody String startScheduling() {
        scheduleAll();
        LOGGER.info("Scheduling of jobs has been started.");
        return "Scheduling of jobs has been started.";
    }
    @RequestMapping(value = {"scheduling/cancel"}, method = RequestMethod.GET)
    public @ResponseBody String cancelScheduling() {
        cancelAll();
        LOGGER.info("Cancelling all scheduled jobs.");
        return "Cancelling all scheduled jobs.";
    }
    private void scheduleAll() {
        LOGGER.info("Scheduling all applications to run.");
        cancelAll();
        //eventually go through the database and load all jobs to be scheduled here.
        schedule(cronConfig());
    }
    /**
     * Cancel all the scheduled reports
     */
    private void cancelAll() {
        for (ScheduledFuture scheduledFuture : scheduledFutures) {
            scheduledFuture.cancel(true);
        }
        scheduledFutures.clear();
    }
    /**
     * Schedule the scheduled report with the given cron schedule information
     */
    private void schedule(String cronSchedule) {
        TimeZone tz = TimeZone.getDefault();
        LOGGER.info("Setting up application {} to execute with cron string: '{}'.", cronSchedule);
        CronTrigger trigger = new CronTrigger(cronSchedule, tz);
        scheduler = scheduler();
        if (scheduler == null) {
            LOGGER.error("Unable to schedule job as scheduler was not found");
            return;
        }
        ScheduledFuture<?> future = scheduler.schedule(new DynamicCron(), trigger);
        scheduledFutures.add(future);
    }
    @Bean
    public TaskScheduler scheduler() {
        if (scheduler == null) {
            ThreadPoolTaskScheduler scheduler = new ThreadPoolTaskScheduler();
            scheduler.setPoolSize(10);
            scheduler.afterPropertiesSet();
        }
        return scheduler;
    }
}