Question

好的，所以我想安排一个任务在每个月的最后一天上午10:10运行。我的cron表达是

0 10 10 L * ?

现在问题是CronSequenceGenerator正在为'L'值抛出NumberFormatException。这意味着Spring的CronSequenceGenerator不支持这种表达式。如何以任何其他方式执行此操作（解决方法）。我不这样做想要使用quartz或者spring会在新版本中支持它。

这是完整的堆栈跟踪：

Exception in thread "main" java.lang.NumberFormatException: For input string: "L"
    at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
    at java.lang.Integer.parseInt(Integer.java:492)
    at java.lang.Integer.valueOf(Integer.java:582)
    at org.springframework.scheduling.support.CronSequenceGenerator.getRange(CronSequenceGenerator.java:324)
    at org.springframework.scheduling.support.CronSequenceGenerator.setNumberHits(CronSequenceGenerator.java:297)
    at org.springframework.scheduling.support.CronSequenceGenerator.setDays(CronSequenceGenerator.java:275)
    at org.springframework.scheduling.support.CronSequenceGenerator.setDaysOfMonth(CronSequenceGenerator.java:266)
    at org.springframework.scheduling.support.CronSequenceGenerator.parse(CronSequenceGenerator.java:239)
    at org.springframework.scheduling.support.CronSequenceGenerator.<init>(CronSequenceGenerator.java:81)
    at org.springframework.scheduling.support.CronTrigger.<init>(CronTrigger.java:54)
    at org.springframework.scheduling.support.CronTrigger.<init>(CronTrigger.java:44)
    at com.hcdc.coedp.datantar.scheduler.SchedulerUtil.start(SchedulerUtil.java:75)
    at com.hcdc.coedp.datantar.scheduler.SchedulerUtil.changeTrigger(SchedulerUtil.java:106)
    at com.hcdc.coedp.datantar.scheduler.SchedulingService.scheduleTransfer(SchedulingService.java:70)
    at com.hcdc.coedp.datantar.scheduler.Scheduler.schedule(Scheduler.java:107)
    at main.Main.main(Main.java:47)

更新

以下是我的安排方法

 /**
    * Schedule a task {@link Task} with a specified cron expression.
    * @param task {@link Task}
    * @param cronExpression cron expression to be applied must be a vaild one.
    * @param taskName
    * @return 
    */
     public String start(Task task, String cronExpression, String taskName) {
        CronTrigger trigger = new CronTrigger(cronExpression);//line 2

        CronSequenceGenerator generator = new CronSequenceGenerator(cronExpression, TimeZone.getTimeZone("GMT+5:30"));
        List<Date> dateList = new ArrayList<>(5);
        Date currentDate = new Date();
        for (int i = 0; i < 5; i++) {
            currentDate = generator.next(currentDate);
            dateList.add((currentDate));
            System.out.println("Next Exceution times are" + currentDate);
        }
        ScheduledFuture sf = tps.schedule(task, trigger);

        //TODO Save this scheduled future with a specific task name.
        ContextHolder.schduledFutureMap.put(taskName, sf);
        return cronExpression;
    }

在第2行，当我传递指定的cron表达式时，它会抛出NumberFormatException。

Answer 1

此功能不在standard cron expression syntax中。所以Spring可能永远不会实现它。查看code，我看不到任何扩展CronSequenceGenerator的外科解决方案。那你为什么不使用Quartz，因为它是particular feature？

根据您的具体需要，您可以实施自己的Trigger。类似的东西：

import java.util.Date;

import org.joda.time.LocalDate;
import org.joda.time.LocalTime;
import org.springframework.scheduling.Trigger;
import org.springframework.scheduling.TriggerContext;

public class LastDayOfMonthTrigger implements Trigger {

    private final LocalTime time;

    public LastDayOfMonthTrigger(LocalTime time) {
        this.time = time;
    }

    @Override
    public Date nextExecutionTime(TriggerContext ctx) {
        Date last = ctx.lastScheduledExecutionTime();
        LocalDate date = last == null ? new LocalDate() : new LocalDate(last).plusDays(1);
        LocalDate lastDay = date.dayOfMonth().withMaximumValue();
        return lastDay.toDateTime(time).toDate();
    }
}

Answer 2

作为一种解决方法，我会安排所有日期的执行

0 10 10 * * ?

并检查计划方法中的实际日期

public void scheduledTask() {
    Calendar c = Calendar.getInstance();
    if (c.get(Calendar.DATE) == c.getActualMaximum(Calendar.DATE)) {
        ...
    }
}

Answer 3

还有另一种解决方法：

生成一个月的数据。该程序应在下个月的第一天运行，以确保捕获整个月的所有数据。

import org.apache.commons.lang3.time.DateUtils;

@Scheduled(cron = "0 0 0 1 * ?") // runs on the first day of each month

public void doStuffOnFirstDayOfMonth() {

    Date now = DateUtils.addDays(new Date(), -1); // "now" is now on the last day of the month

}

CronSequenceGenerator的解决方法最后一个月？

3 个答案: