Cronexpression expression explanation and cases

1. cron Expression format ：

{ Number of seconds } { minute } { Hours } { date } { month } { week } { year ( May be empty )}

2. cron The expressions are interpreted as ：

{ Number of seconds } ==> Allowed value range : 0~59 , Null values are not allowed , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*"  Represents every 1 Second trigger ;

","  Represents a trigger in a specified number of seconds , such as "0,15,45" representative 0 second 、15 The second and 45 The task is triggered in seconds

"-"  Represents a trigger within a specified range , such as "25-45" For from 25 Seconds start to trigger to 45 Second end trigger , every other 1 Second trigger 1 Time

"/"  Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "0"), The following value represents the offset , such as "0/20" perhaps "*/20" For from 0 Two seconds to start , every other 20 Second trigger 1 Time , namely 0 Second trigger 1 Time ,20 Second trigger 1 Time ,40 Second trigger 1 Time ;"5/20" representative 5 Second trigger 1 Time ,25 Second trigger 1 Time ,45 Second trigger 1 Time ;"10-45/20" On behalf of the [10,45] Inner stepping 20 Second hit time trigger , namely 10 Second trigger 1 Time ,30 Second trigger 1 Time

{ minute } ==> Allowed value range : 0~59 , Null values are not allowed , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*"  Represents every 1 Minutes to trigger ;

","  Represents triggering in a specified minute , such as "10,20,40" representative 10 minute 、20 Minutes and 40 The task is triggered in minutes

"-"  Represents a trigger within a specified range , such as "5-30" For from 5 Minutes start to trigger to 30 The minute is over   Hair , every other 1 Minutes to trigger

"/"  Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "0"), The following value represents the offset , such as "0/25" perhaps "*/25" For from 0 minutes , every other 25 Minutes to trigger 1 Time , namely 0 Minutes to trigger 1 Time , The first 25 Minutes to trigger 1 Time , The first 50 Minutes to trigger 1 Time ;"5/25" representative 5 Minutes to trigger 1 Time ,30 Minutes to trigger 1 Time ,55 Minutes to trigger 1 Time ;"10-45/20" On behalf of the [10,45] Inner stepping 20 Minute hit time trigger , namely 10 Minutes to trigger 1 Time ,30 Minutes to trigger 1 Time

{ Hours } ==> Allowed value range : 0~23 , Null values are not allowed , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*"  Represents every 1 Hours trigger ;

","  Represents triggering at a specified point in time , such as "10,20,23" representative 10 O 'clock 、20 O'clock and 23 Click trigger task

"-"  Represents a trigger within a specified period of time , such as "20-23" For from 20 It starts to trigger to 23 Point end trigger , every other 1 Hours trigger

"/"  Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "0"), The following value represents the offset , such as "0/1" perhaps "*/1" For from 0 It starts to trigger , every other 1 Hours trigger 1 Time ;"1/2" For from 1 It starts to trigger , After every 2 Trigger once per hour ;"19-20/2" The expression will only be in 19 Some trigger

{ date } ==> Allowed value range : 1~31 , Null values are not allowed , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*"  It's a daily trigger ;

"?"  And { week } Mutually exclusive , It means that if it is clearly specified that { week } Trigger , said { date } meaningless , So as not to cause   Conflict and chaos

","  Represents a trigger on a specified date , such as "1,10,20" representative 1 Number 、10 Number and 20 This is the number one 3 God trigger

"-"  Represents a trigger within a specified date range , such as "10-15" For from 10 It's starting to trigger 15 The end of the number one triggers , every other 1 God trigger

"/"  Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "1"), The following value represents the offset , such as "1/5" perhaps "*/5" For from 1 It's starting to fire , every other 5 God trigger 1 Time ;"10/5" For from 10 It's starting to fire , After every 5 Once a day ;"1-10/2" The expression means in [1,10] Within the scope of , every other 2 God trigger , namely 1 Number ,3 Number ,5 Number ,7 Number ,9 No. triggers

"L"  If { date } If it's "L", That means the last day of the month triggers

"W " It means to trigger on the nearest working day of the month , The so-called recent working day , That is the shortest distance from the day to the working day , If that day is a working day , Then the distance is 0; The so-called saying of this month , I just can't get the latest working day across the month , Even before / The last day of the following month / The first day does satisfy the most recent working day ; therefore ,"LW" It means the last working day of the month triggers ,"W" Strong dependence on { month }

"C"  Trigger according to the calendar , Because of less use , No explanation for the moment

{ month } ==> Allowed value range : 1~12 (JAN-DEC), Null values are not allowed , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*"  It means every month ;

","  Represents a trigger in a specified month , such as "1,6,12" representative 1 month 、6 Month and 12 Month triggers mission

"-"  Represents a trigger within a specified range of months , such as "1-6" For from 1 The month begins to trigger to 6 The end of the month triggers , every other 1 Three months to trigger

"/"  Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "1"), The following value represents the offset , such as "1/2" perhaps "*/2" For from 1 The month starts to trigger , every other 2 Three months to trigger 1 Time ;"6/6" For from 6 The month starts to trigger , After every 6 Once a month ;"1-6/12" The expression means every year 1 Month triggers

  

{ week } ==> Allowed value range : 1~7 (SUN-SAT),1 For Sunday ( The first day of the week ), And so on ,7 On behalf of Saturday ( The last day of the week ), Null values are not allowed , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*"  It means every week ;

"?"  And { date } Mutually exclusive , It means that if it is clearly specified that { date } Trigger , said { week } meaningless , So as not to cause conflict and confusion

","  On behalf of the appointed week to trigger , such as "1,3,5" For Sunday 、 Tuesday and Thursday trigger

"-"  Represents triggering within the specified week range , such as "2-4" Representatives trigger from Monday to Wednesday , every other 1 God trigger

"/"  Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "1"), The following value represents the offset , such as "1/3" perhaps "*/3" It's on Sunday , every other 3 God trigger 1 Time ;"1-5/2" The expression means in [1,5] Within the scope of , every other 2 God trigger , It's Sunday 、 Tuesday 、 Thursday triggers

"L"  If { week } If it's "L", That means the last day of the week triggers , It's Saturday ,L= 7 perhaps L = SAT, therefore ,"5L" It means the last Thursday of the month

"#"  Used to specify a specific number of weeks ,"#" The front represents the week ,"#" The following represents the week of the month , such as "2#2" Monday of the second week of this month ,"5#3" It means Thursday of the third week of this month , therefore ,"5L" This form is just "#" It's just a special form of

"C"  Trigger according to the calendar , Because of less use , No explanation for the moment

{ year } ==> Allowed value range : 1970~2099 , Allow null , If the value is illegal , The scheduler will throw SchedulerException abnormal

"*" It means every year ;

"," It means that it is triggered only in the specified year , such as "2011,2012,2013" representative 2011 year 、2012 Years and 2013 Year trigger mission

"-" Represents a trigger within the specified year range , such as "2011-2020" For from 2011 It began to trigger to 2020 The end of the year triggers , every other 1 Year trigger

"/" Represents trigger step (step),"/" The preceding values represent the initial values ("*" equivalent "1970"), The following value represents the offset , such as "2011/2" perhaps "*/2" For from 2011 It's starting to trigger , every other 2 Year trigger 1 Time

  

Be careful ： except { date } and { week } have access to "?" To achieve mutual exclusion , Beyond expressing meaningless information , Other placeholders should have specific time meanings , And the dependence is ： year -> month -> date ( week )-> Hours -> minute -> Number of seconds

  

3. cron The powerful charm of expression lies in its flexible horizontal and vertical combination and simple syntax , use cron Expressions can write almost any time point you want to trigger

Classic case ：

"30 * * * * ?" Trigger the mission every half minute

"1 0 0 *  *  ?" Every day 0 when 0 branch 0 Execute the task in seconds

"30 10 * * * ?" Hourly 10 branch 30 Second trigger task

"30 10 1 * * ?" Every day 1 spot 10 branch 30 Second trigger task

"30 10 1 20 * ?" monthly 20 Number 1 spot 10 branch 30 Second trigger task

"30 10 1 20 10 ? *" Every year, 10 month 20 Number 1 spot 10 branch 30 Second trigger task

"30 10 1 20 10 ? 2011" 2011 year 10 month 20 Number 1 spot 10 branch 30 Second trigger task

"30 10 1 ? 10 * 2011" 2011 year 10 Every day, every month 1 spot 10 branch 30 Second trigger task

"30 10 1 ? 10 SUN 2011" 2011 year 10 Every Sunday every month 1 spot 10 branch 30 Second trigger task

"15,30,45 * * * * ?" Every time 15 second ,30 second ,45 The task is triggered in seconds

"15-45 * * * * ?" 15 To 45 Seconds , Every second a mission is triggered

"15/5 * * * * ?" Every minute of every minute 15 Seconds to trigger , every other 5 Second trigger once

"15-30/5 * * * * ?" Every minute 15 Seconds to 30 It starts to fire in seconds , every other 5 Second trigger once

"0 0/3 * * * ?" At the end of every hour 0 branch 0 Seconds to start , Trigger every three minutes

"0 15 10 ? * MON-FRI" Monday to Friday 10 spot 15 branch 0 Second trigger task

"0 15 10 L * ?" On the last day of every month 10 spot 15 branch 0 Second trigger task

"0 15 10 LW * ?" On the last working day of every month 10 spot 15 branch 0 Second trigger task

"0 15 10 ? * 5L" On the last Thursday of every month 10 spot 15 branch 0 Second trigger task

"0 15 10 ? * 5#3" On Thursdays of the third week of every month 10 spot 15 branch 0 Second trigger task