2016年1月5日 星期二

cron 表達式詳解 日期表達式

quartz cron 表達式詳解
字段                允許值                              允許的特殊字符 
秒                    0-59                                , - * / 
分                    0-59                                , - * / 
小時                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(可選)      留空, 1970-2099              , - * /

The '*' character is used to specify all values. For example, "*" in the minute field means "every minute". 
「*」字符被用來指定所有的值。如: *「在分鐘的字段域裡表示「每分鐘」。

The '?' character is allowed for the day-of-month and 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。它被用來指定「非明確的值」。當你需要通過在這兩個域中的一個來指定一些東西的時候,它是有用的。看下面的例子你就會明白。
月份中的日期和星期中的日期這兩個元素時互斥的一起應該通過設置一個問號(?)來表明不想設置那個字段。

The '-' character is used to specify ranges For example "10-12" in the hour field means "the hours 10, 11 and 12". 
「-」字符被用來指定一個範圍。如:「10-12」在小時域意味著「10點、11點、12點」。

The ',' character is used to specify additional values. For example "MON,WED,FRI" in the day-of-week field means "the days Monday, Wednesday, and Friday". 
「,」字符被用來指定另外的值。如:「MON,WED,FRI」在星期域裡表示」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 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. 
「/」字符用於指定增量。如:「0/15」在秒域意思是沒分鐘的0,15,30和45秒。「5/15」在分鐘域表示沒小時的5,20,35 和50。符號「*」在「/」前面(如:*/10)等價於0在「/」前面(如:0/10)。記住一條本質:表達式的每個數值域都是一個有最大值和最小值的集合,如:秒域和分鐘域的集合是0-59,日期域是1-31,月份域是1-12。字符「/」可以幫助你在每個字符域中取相應的數值。如:「7/6」在月份域的時候只有當7月的時候才會觸發,並不是表示每個6月。

The 'L' character is allowed for the day-of-month and 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 day-of-month field means "the last day of the month" - day 31 for January, day 28 for February on non-leap years. If used in the day-of-week field by itself, it simply means "7" or "SAT". But if used in the day-of-week field after another value, it means "the last xxx day of the month" - for example "6L" means "the last friday 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. 
L是『last'的省略寫法可以表示day-of-month和day-of-week域,但在兩個字段中的意思不同,例如day- of-month域中表示一個月的最後一天。如果在day-of-week域表示『7』或者『SAT',如果在day-of-week域中前面加上數字,它表示一個月的最後幾天,例如『6L'就表示一個月的最後一個星期五。

The 'W' character is allowed for the day-of-month field. This character is used to specify the weekday (Monday-Friday) nearest the given day. As an example, if you were to specify "15W" as the value for the day-of-month field, the meaning is: "the nearest weekday to the 15th of the month". So if the 15th is a Saturday, the trigger will fire on Friday the 14th. If the 15th is a Sunday, the trigger will fire on Monday the 16th. If the 15th is a Tuesday, then it will fire on Tuesday the 15th. However if you specify "1W" as the value for day-of-month, and the 1st is a Saturday, the trigger will fire on Monday the 3rd, as it will not 'jump' over the boundary of a month's days. The 'W' character can only be specified when the day-of-month is a single day, not a range or list of days
The 'L' and 'W' characters can also be combined for the day-of-month expression to yield 'LW', which translates to "last weekday of the month". 
字符「W」只允許日期域出現。這個字符用於指定日期的最近工作日。例如:如果你在日期域中寫 「15W」,表示:這個月15號最近的工作日。所以,如果15號是週六,則任務會在14號觸發。如果15好是週日,則任務會在週一也就是16號觸發。如果是在日期域填寫「1W」即使1號是週六,那麼任務也只會在下週一,也就是3號觸發,「W」字符指定的最近工作日是不能夠跨月份的。字符「W」只能配合一個單獨的數值使用,不能夠是一個數字段,如:1-15W是錯誤的。
「L」和「W」可以在日期域中聯合使用,LW表示這個月最後一週的工作日。

The '#' character is allowed for the day-of-week field. This character is used to specify "the nth" XXX day of the month. For example, the value of "6#3" in the day-of-week field means the third Friday of the month (day 6 = Friday and "#3" = the 3rd one in the month). Other examples: "2#1" = the first Monday of the month and "4#5" = the fifth Wednesday of the month. Note that if you specify "#5" and there is not 5 of the given day-of-week in the month, then no firing will occur that month. 
字符「#」只允許在星期域中出現。這個字符用於指定本月的某某天。例如:「6#3」表示本月第三週的星期五(6表示星期五,3表示第三週)。「2#1」表示本月第一週的星期一。「4#5」表示第五週的星期三。

The 'C' character is allowed for the day-of-month and 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 day-of-month field means "the first day included by the calendar on or after the 5th". A value of "1C" in the day-of-week field means "the first day included by the calendar on or after sunday". 
字符「C」允許在日期域和星期域出現。這個字符依靠一個指定的「日曆」。也就是說這個表達式的值依賴於相關的「日曆」的計算結果,如果沒有 「日曆」關聯,則等價於所有包含的「日曆」。如:日期域是「5C」表示關聯「日曆」中第一天,或者這個月開始的第一天的後5天。星期域是「1C」表示關聯 「日曆」中第一天,或者星期的第一天的後1天,也就是週日的後一天(週一)。

表達式舉例:
"0 0 12 * * ?" 每天中午12點觸發
"0 15 10 ? * *" 每天上午10:15觸發
"0 15 10 * * ?" 每天上午10:15觸發
"0 15 10 * * ? *" 每天上午10:15觸發
"0 15 10 * * ? 2005" 2005年的每天上午10:15觸發
"0 * 14 * * ?" 在每天下午2點到下午2:59期間的每1分鐘觸發
"0 0/5 14 * * ?" 在每天下午2點到下午2:55期間的每5分鐘觸發
"0 0/5 14,18 * * ?" 在每天下午2點到2:55期間和下午6點到6:55期間的每5分鐘觸發
"0 0-5 14 * * ?" 在每天下午2點到下午2:05期間的每1分鐘觸發
"0 10,44 14 ? 3 WED" 每年三月的星期三的下午2:10和2:44觸發
"0 15 10 ? * MON-FRI" 週一至週五的上午10:15觸發
"0 15 10 15 * ?" 每月15日上午10:15觸發
"0 15 10 L * ?" 每月最後一日的上午10:15觸發
"0 15 10 ? * 6L" 每月的最後一個星期五上午10:15觸發
"0 15 10 ? * 6L 2002-2005" 2002年至2005年的每月的最後一個星期五上午10:15觸發
"0 15 10 ? * 6#3" 每月的第三個星期五上午10:15觸發

quartz的高級特性
1 數據庫存儲 
2 集群支持 
3 數據庫持久化任務,trigger 
4 trigger 的停止,運行 
5 任務的任意添加 
6 比corntrigger 更詳盡的任務安排 
7 線程的內部數據交換

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