java - CronSequenceGenerator 的解决方法是每月的最后一天？

Question

好的，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 表达式是

0 10 10 L * ?

现在的问题是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(解决方法)执行此操作。我不想使用 quartz 或者 spring 是否会在新的中支持它发布。

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:

以下是我的调度方法

 /**
    * 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。看着 code ，我看不到任何扩展 CronSequenceGenerator 的手术解决方案。那么为什么你不使用 Quartz 因为它是一个 particular feature ？

根据您的具体需要，您可以实现自己的 Trigger .像这样的东西:

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();
    }
}