如何让 Quartz 每第 n 个月启动一次工作而不会在一月份中断？

Question

我希望 Quartz 在每五个月的每个第三周的第五天执行作业。我这样做： 0 0 10 ？ */5 5#3

问题是 cron 调度程序在这种情况下绑定到年份。所以实际上它在每年的1、6、11月执行计划。但我希望它从当月开始透明地执行。比如明年4、9、2，明年7e.t.c。怎么做到的？

我知道有 CalendarIntervalSchedule 可以执行此操作，但它不允许我执行此操作 "fifth day of every third week"。

Answer 1

不要认为你可以用一条规则做到这一点。

您必须创建多个明确指定月份和年份组合的规则：

0 0 10 ? 1,6,11 5#3 2015,2020,2025,2030
0 0 10 ? 4,9 5#3 2016,2021,2026,2031
0 0 10 ? 2,7,12 5#3 2017,2022,2027,2032
0 0 10 ? 5,10 5#3 2018,2023,2028,2033
0 0 10 ? 3,8 5#3 2019,2024,2029,2034

Answer 2

Quartz 调度程序允许您为每个作业指定多个 CronTrigger。因此，您可以创建几个较小的表达式来协同工作，而不是创建一个单一的多用途表达式。

我想到了这些：

0 0 10 ? 1,6,11 5#3 2015/5
0 0 10 ? 4,9 5#3 2016/5
0 0 10 ? 2,7,12 5#3 2017/5
0 0 10 ? 5,10 5#3 2018/5
0 0 10 ? 3,8 5#3 2019/5

唯一的缺点是您必须在一开始就指定开始年份，但我想您可以轻松地实现自动化。

祝你好运！ ;)

Answer 3

对于我的任务，我找到了更好的解决方案。我创建了一个日历，其中仅包含从指定日期开始的指定时间间隔的月份。所有其他月份将被拒绝。

这对我来说更容易，因为我不需要 create/manage 很多工作的触发器。

[Serializable]
public class MonthIntervalCalendar : BaseCalendar
{
    DateTime _startAt;
    int _interval;

    /// <summary>
    /// Initializes a new instance of the <see cref="MonthIntervalCalendar"/> class.
    /// </summary>
    public MonthIntervalCalendar(DateTime startAt, int interval)
    {
        _startAt = startAt;
        _interval = interval;
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="MonthIntervalCalendar"/> class.
    /// </summary>
    /// <param name="baseCalendar">The base calendar.</param>
    public MonthIntervalCalendar(DateTime startAt, int interval, ICalendar baseCalendar)
    {
        _startAt = startAt;
        _interval = interval;
        CalendarBase = baseCalendar;
    }

    public override bool IsTimeIncluded(DateTimeOffset timeStampUtc)
    {
        if (!base.IsTimeIncluded(timeStampUtc))
            return false;
        if (timeStampUtc < _startAt)
            return false;

        var months = (timeStampUtc.Month - _startAt.Month) + 12 * (timeStampUtc.Year - _startAt.Year);
        var included = months % _interval == 0;
        return included;
    }

    /// <summary>
    /// Determine the next time (in milliseconds) that is 'included' by the
    /// Calendar after the given time.
    /// <para>
    /// Note that this Calendar is only has full-day precision.
    /// </para>
    /// </summary>
    public override DateTimeOffset GetNextIncludedTimeUtc(DateTimeOffset timeUtc)
    {
        timeUtc = base.GetNextIncludedTimeUtc(timeUtc);
        while (!IsTimeIncluded(timeUtc))
        {
            var nextTime = timeUtc.AddMonths(1);
            timeUtc = base.GetNextIncludedTimeUtc( new DateTime(nextTime.Year, nextTime.Month, 1) );
        }
        return timeUtc;
    }

    /// <summary>
    /// Creates a new object that is a copy of the current instance.
    /// </summary>
    /// <returns>A new object that is a copy of this instance.</returns>
    public override object Clone()
    {
        MonthIntervalCalendar clone = (MonthIntervalCalendar)base.Clone();
        clone._interval = _interval;
        clone._startAt = _startAt;
        return clone;
    }

    public override int GetHashCode()
    {
        int baseHash = 0;
        if (GetBaseCalendar() != null)
            baseHash = GetBaseCalendar().GetHashCode();
        return _startAt.GetHashCode() + _interval + 5 * baseHash;
    }

    public bool Equals(MonthIntervalCalendar obj)
    {
        if (obj == null)
            return false;
        bool baseEqual = GetBaseCalendar() == null || GetBaseCalendar().Equals(obj.GetBaseCalendar());

        return baseEqual && obj._startAt.Equals(_startAt) && obj._interval.Equals(_interval);
    }

    public override bool Equals(object obj)
    {
        if ((obj == null) || !(obj is MonthIntervalCalendar))
            return false;
        return Equals((MonthIntervalCalendar)obj);
    }
}

如何让 Quartz 每第 n 个月启动一次工作而不会在一月份中断？

How to make Quartz launch job every nth month with no interrupt at january?

c#

quartz-scheduler

quartz.net