java - 在下次调用之前中断 spring scheduler 任务

Question

我有一个 Spring-Boot 应用程序，它将成为我们想要触发的其他几个进程的编排服务。我目前使用 Spring Scheduling 从数据库中动态拉取 crons 来设置它。我加入了一个 rest 方法来触发从数据库中提取新的 cron 信息的过程。这个逻辑都正常工作。唯一的“问题”是它在下一次计划运行到达真正的问题之前不使用新的 cron 信息。 有没有办法中断当前的Trigger，并使用更新的cron信息重新调度一个。这里是应用程序供引用:

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";
    }
}

Answer 1

因此，使用 SchedulingConfigurer->configureTasks，您无法访问我正在使用的 Spring 版本 (4.2.7.RELEASE) 中的 ScheduledFuture(s)。从我读过的几篇文章中，它被提到为 future 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;
    }
}

这基本上复制了 ScheduledTaskRegistrar 提供的允许您管理 ScheduledFuture(s) 的功能。希望这可以在将来帮助其他人。