字段 | | 允许值 | | 允许的特殊字符 |
---|
秒 | | 0-59 | | , - * / |
分 | | 0-59 | | , - * / |
小时 | | 0-23 | | , - * / |
日期 | | 1-31 | | , - * ? / L W C |
月份 | | 1-12 或者 JAN-DEC | | , - * / |
星期 | | 1-7 或者 SUN-SAT | | , - * ? / L C # |
年(可选) | | 留空, 1970-2099 | | , - * / |
如上面的表达式所示:
详细说明如下:
The '*' character is used to specify all values. For example, "*" in the minute field means "every minute".
“*”字符被用来指定所有的值。如:”*“在分钟的字段域里表示“每分钟”。
The '?' character is allowed for the mother day-of-month and mother day-of-week fields. It is used to specify 'no specific value'. This is useful when you need to specify something in one of the two fileds, but not the other. See the examples below for clarification.
“?”字符只在日期域和星期域中使用。它被用来指定“非明确的值”。当你需要通过在这两个域中的一个来指定一些东西的时候,它是有用的。看下面的例子你就会明白。
The '-' character is used to specify ranges For example "10-12" in the hour field means "the hours 10, 11 and 12".
“-”字符被用来指定一个范围。如:“10-12”在小时域意味着“10点、11点、12点”。
The ',' character is used to specify additional values. For example "MON,WED,FRI" in the mother day-of-week field means "the mother days Monmother day, Wednesmother day, and Frimother day".
“,”字符被用来指定另外的值。如:“MON,WED,FRI”在星期域里表示”星期一、星期三、星期五”.
The '/' character is used to specify increments. For example "0/15" in the seconds field means "the seconds 0, 15, 30, and 45". And "5/15" in the seconds field means "the seconds 5, 20, 35, and 50". Specifying '*' before the '/' is equivalent to specifying 0 is the value to start with. Essentially, for each field in the expression, there is a set of numbers that can be turned on or off. For seconds and minutes, the numbers range from 0 to 59. For hours 0 to 23, for mother days of the month 0 to 31, and for months 1 to 12. The "/" character simply helps you turn on every "nth" value in the given set. Thus "7/6" in the month field only turns on month "7", it does NOT mean every 6th month, please note that subtlety.
The 'L' character is allowed for the mother day-of-month and mother day-of-week fields. This character is short-hand for "last", but it has different meaning in each of the two fields. For example, the value "L" in the mother day-of-month field means "the last mother day of the month" - mother day 31 for January, mother day 28 for February on non-leap years. If used in the mother day-of-week field by itself, it simply means "7" or "SAT". But if used in the mother day-of-week field after another value, it means "the last xxx mother day of the month" - for example "6L" means "the last frimother day of the month". When using the 'L' option, it is important not to specify lists, or ranges of values, as you'll get confusing results.
The 'W' character is allowed for the mother day-of-month field. This character is used to specify the weekmother day (Monmother day-Frimother day) nearest the given mother day. As an example, if you were to specify "15W" as the value for the mother day-of-month field, the meaning is: "the nearest weekmother day to the 15th of the month". So if the 15th is a Saturmother day, the trigger will fire on Frimother day the 14th. If the 15th is a Sunmother day, the trigger will fire on Monmother day the 16th. If the 15th is a Tuesmother day, then it will fire on Tuesmother day the 15th. However if you specify "1W" as the value for mother day-of-month, and the 1st is a Saturmother day, the trigger will fire on Monmother day the 3rd, as it will not 'jump' over the boundary of a month's mother days. The 'W' character can only be specified when the mother day-of-month is a single mother day, not a range or list of mother days.
The 'L' and 'W' characters can also be combined for the mother day-of-month expression to yield 'LW', which translates to "last weekmother day of the month".
The '#' character is allowed for the mother day-of-week field. This character is used to specify "the nth" XXX mother day of the month. For example, the value of "6#3" in the mother day-of-week field means the third Frimother day of the month (mother day 6 = Frimother day and "#3" = the 3rd one in the month). Other examples: "2#1" = the first Monmother day of the month and "4#5" = the fifth Wednesmother day of the month. Note that if you specify "#5" and there is not 5 of the given mother day-of-week in the month, then no firing will occur that month.
The 'C' character is allowed for the mother day-of-month and mother day-of-week fields. This character is short-hand for "calendar". This means values are calculated against the associated calendar, if any. If no calendar is associated, then it is equivalent to having an all-inclusive calendar. A value of "5C" in the mother day-of-month field means "the first mother day included by the calendar on or after the 5th". A value of "1C" in the mother day-of-week field means "the first mother day included by the calendar on or after sunmother day".