• Quartz学习笔记


    The Quartz JAR Files

    The Quartz package includes a number of jar files, located in root directory of the distribution. The main Quartz library is named quartz-all-xxx.jar (where xxx is a version number). In order to use any of Quartz's features, this jar must be located on your application's classpath.

    The Properties File

    Quartz uses a properties file called (kudos on the originality) quartz.properties. This isn't necessary at first, but to use anything but the most basic configuration it must be located on your classpath.

    using Quartz

    Here's a quick snippet of code, that instantiates and starts a scheduler, and schedules a job for execution:

    1.create a Job class

    2.Instantiate a scheduler

    3.Instantiate a job and a trigger

    4. Translate any state argument with JobDataMap

    The JobDataMap can be used to hold any amount of (serializable) data objects which you wish to have made available to the job instance when it executes. JobDataMap is an implementation of the Java Map interface, and has some added convenience methods for storing and retrieving data of primitive types.

    5.Tell scheldule to tie some job with some trigger

    6.start up a scheldule

    7.shutdown a scheldule

    注:只有quartz 1.8以下的版本才支持对spring的集成

    在项目中使用quartz完成定时任务

    1.加入依赖

    <properties></properties>中添加quartz的版本:

    <dependencies></dependencies>中添加quarz的依赖:

    2.定义版本发布的定时任务类

    3.注入调度器

    4.VersionService中使用quartz schedule实现定时发布任务

        1.定义SchedulerFactory

        

      

        2.定义一个全局的JobList

        

      

        3.在生成版本的方法中添加任务

        

      

        4.添加一个job

      

      5.删除一个job

      

        6.关闭调度器

          

        7.删除版本时,同时删除对应的job

          

    Cron Expressions

    Cron-Expressions are used to configure instances of CronTrigger. Cron-Expressions are strings that are actually made up of seven sub-expressions, that describe individual details of the schedule. These sub-expression are separated with white-space, and represent:

    1. Seconds
    2. Minutes
    3. Hours
    4. Day-of-Month
    5. Month
    6. Day-of-Week
    7. Year (optional field)

    An example of a complete cron-expression is the string "0 0 12 ? * WED" - which means "every Wednesday at 12:00:00 pm".

    Individual sub-expressions can contain ranges and/or lists. For example, the day of week field in the previous (which reads "WED") example could be replaced with "MON-FRI", "MON,WED,FRI", or even "MON-WED,SAT".

    Wild-cards (the '' character) can be used to say "every" possible value of this field. Therefore the '' character in the "Month" field of the previous example simply means "every month". A '*' in the Day-Of-Week field would therefore obviously mean "every day of the week".

    All of the fields have a set of valid values that can be specified. These values should be fairly obvious - such as the numbers 0 to 59 for seconds and minutes, and the values 0 to 23 for hours. Day-of-Month can be any value 1-31, but you need to be careful about how many days are in a given month! Months can be specified as values between 0 and 11, or by using the strings JAN, FEB, MAR, APR, MAY, JUN, JUL, AUG, SEP, OCT, NOV and DEC. Days-of-Week can be specified as values between 1 and 7 (1 = Sunday) or by using the strings SUN, MON, TUE, WED, THU, FRI and SAT.

    The '/' character can be used to specify increments to values. For example, if you put '0/15' in the Minutes field, it means 'every 15th minute of the hour, starting at minute zero'. If you used '3/20' in the Minutes field, it would mean 'every 20th minute of the hour, starting at minute three' - or in other words it is the same as specifying '3,23,43' in the Minutes field. Note the subtlety that "/35" does *not mean "every 35 minutes" - it mean "every 35th minute of the hour, starting at minute zero" - or in other words the same as specifying '0,35'.

    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 fields, but not the other. See the examples below (and CronTrigger JavaDoc) for clarification.

    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" or "FRIL" both mean "the last friday of the month". You can also specify an offset from the last day of the month, such as "L-3" which would mean the third-to-last day of the calendar month. When using the 'L' option, it is important not to specify lists, or ranges of values, as you'll get confusing/unexpected results.

    The 'W' 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".

    The '#' is used to specify "the nth" XXX weekday of the month. For example, the value of "6#3" or "FRI#3" in the day-of-week field means "the third Friday of the month".

    Here are a few more examples of expressions and their meanings - you can find even more in the JavaDoc for org.quartz.CronExpression

    Example Cron Expressions

    CronTrigger Example 1 - an expression to create a trigger that simply fires every 5 minutes

    "0 0/5 * * * ?"

    CronTrigger Example 2 - an expression to create a trigger that fires every 5 minutes, at 10 seconds after the minute (i.e. 10:00:10 am, 10:05:10 am, etc.).

    "10 0/5 * * * ?"

    CronTrigger Example 3 - an expression to create a trigger that fires at 10:30, 11:30, 12:30, and 13:30, on every Wednesday and Friday.

    "0 30 10-13 ? * WED,FRI"

    CronTrigger Example 4 - an expression to create a trigger that fires every half hour between the hours of 8 am and 10 am on the 5th and 20th of every month. Note that the trigger will NOT fire at 10:00 am, just at 8:00, 8:30, 9:00 and 9:30

    "0 0/30 8-9 5,20 * ?"

    Note that some scheduling requirements are too complicated to express with a single trigger - such as "every 5 minutes between 9:00 am and 10:00 am, and every 20 minutes between 1:00 pm and 10:00 pm". The solution in this scenario is to simply create two triggers, and register both of them to run the same job.

    Quartz and Spring Integration

    http://techo-ecco.com/blog/quartz-and-spring-integration/

    quartz-2.0.2学习小记

    http://blog.csdn.net/cuihaiyang/article/details/6742869

    Task Execution and Scheduling

    http://static.springsource.org/spring/docs/3.0.5.RELEASE/reference/scheduling.html

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  • 原文地址:https://www.cnblogs.com/luowei010101/p/2561030.html
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