java scheduler系统 － Quartz学习

java如何实现一个scheduler系统

The public interface for inspecting settings specific to a CronTrigger, . which is used to fire a Job at given moments in time, defined with Unix 'cron-like' schedule definitions.

For those unfamiliar with "cron", this means being able to create a firing schedule such as: "At 8:00am every Monday through Friday" or "At 1:30am every last Friday of the month".

The format of a "Cron-Expression" string is documented on the CronExpression class.

Here are some full examples: 

Expression		Meaning
"0 0 12 * * ?"		Fire at 12pm (noon) every day
"0 15 10 ? * *"		Fire at 10:15am every day
"0 15 10 * * ?"		Fire at 10:15am every day
"0 15 10 * * ? *"		Fire at 10:15am every day
"0 15 10 * * ? 2005"		Fire at 10:15am every day during the year 2005
"0 * 14 * * ?"		Fire every minute starting at 2pm and ending at 2:59pm, every day
"0 0/5 14 * * ?"		Fire every 5 minutes starting at 2pm and ending at 2:55pm, every day
"0 0/5 14,18 * * ?"		Fire every 5 minutes starting at 2pm and ending at 2:55pm, AND fire every 5 minutes starting at 6pm and ending at 6:55pm, every day
"0 0-5 14 * * ?"		Fire every minute starting at 2pm and ending at 2:05pm, every day
"0 10,44 14 ? 3 WED"		Fire at 2:10pm and at 2:44pm every Wednesday in the month of March.
"0 15 10 ? * MON-FRI"		Fire at 10:15am every Monday, Tuesday, Wednesday, Thursday and Friday
"0 15 10 15 * ?"		Fire at 10:15am on the 15th day of every month
"0 15 10 L * ?"		Fire at 10:15am on the last day of every month
"0 15 10 ? * 6L"		Fire at 10:15am on the last Friday of every month
"0 15 10 ? * 6L"		Fire at 10:15am on the last Friday of every month
"0 15 10 ? * 6L 2002-2005"		Fire at 10:15am on every last Friday of every month during the years 2002, 2003, 2004 and 2005
"0 15 10 ? * 6#3"		Fire at 10:15am on the third Friday of every month

Please also refer to http://www.quartz-scheduler.org/documentation/quartz-2.x/tutorials/tutorial-lesson-06