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Problem description and solution process summary

Problem description
First of all, there is a timer in this project, and then it seems that the timing task error causes the project not to start up, but it is not.

2020-11-19 15:22:06.141 [restartedMain] INFO  com.alibaba.druid.pool.DruidDataSource 1609 - {dataSource-1} closed
2020-11-19 15:22:06.952  INFO 1352 --- [lerFactoryBean]] o.s.s.quartz.SchedulerFactoryBean        : Starting Quartz Scheduler now, after delay of 1 seconds
2020-11-19 15:22:06.952 [Quartz Scheduler [schedulerFactoryBean]] INFO  org.springframework.scheduling.quartz.SchedulerFactoryBean 665 - Starting Quartz Scheduler now, after delay of 1 seconds
Exception in thread "Quartz Scheduler [schedulerFactoryBean]" org.springframework.scheduling.SchedulingException: Could not start Quartz Scheduler after delay; nested exception is org.quartz.SchedulerException: The Scheduler cannot be restarted after shutdown() has been called.
	at org.springframework.scheduling.quartz.SchedulerFactoryBean$1.run(SchedulerFactoryBean.java:671)
Caused by: org.quartz.SchedulerException: The Scheduler cannot be restarted after shutdown() has been called.
	at org.quartz.core.QuartzScheduler.start(QuartzScheduler.java:557)
	at org.quartz.impl.StdScheduler.start(StdScheduler.java:142)
	at org.springframework.scheduling.quartz.SchedulerFactoryBean$1.run(SchedulerFactoryBean.java:668)

To solve the process
At the beginning, I always thought that the project could not be started due to the timing task, but I ignored the error log above. I searched a lot about the timer error, but I couldn’t solve it. And then it turned out that there was another error. The Mybatis mapping file resultMap is filled incorrectly. It will be all right after the changes are done.

conclusion
In the face of error, must be calm and calm, good observation of the log. Only after observing the log can you quickly lock the cause of the error.