走断点时因为延迟的原因不会发生，直接运行执行器总是会走到 destroy（），而toStop()的registryThread总是为空。
11:10:30.030 logback [main] INFO c.e.demo.ChahuashiServiceApplication - Started ChahuashiServiceApplication in 0.932 seconds (JVM running for 1.763)
11:10:30.034 logback [SpringContextShutdownHook] INFO o.s.s.c.ThreadPoolTaskExecutor - Shutting down ExecutorService 'applicationTaskExecutor'
11:10:30.038 logback [SpringContextShutdownHook] ERROR c.x.job.core.executor.XxlJobExecutor - null
java.lang.NullPointerException: null
at com.xxl.job.core.thread.ExecutorRegistryThread.toStop(ExecutorRegistryThread.java:117)
at com.xxl.job.core.server.EmbedServer.stopRegistry(EmbedServer.java:262)
at com.xxl.job.core.server.EmbedServer.stop(EmbedServer.java:124)
at com.xxl.job.core.executor.XxlJobExecutor.stopEmbedServer(XxlJobExecutor.java:158)
at com.xxl.job.core.executor.XxlJobExecutor.destroy(XxlJobExecutor.java:85)
at com.xxl.job.core.executor.impl.XxlJobSpringExecutor.destroy(XxlJobSpringExecutor.java:55)
at org.springframework.beans.factory.support.DisposableBeanAdapter.destroy(DisposableBeanAdapter.java:258)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroyBean(DefaultSingletonBeanRegistry.java:579)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroySingleton(DefaultSingletonBeanRegistry.java:551)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.destroySingleton(DefaultListableBeanFactory.java:1089)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroySingletons(DefaultSingletonBeanRegistry.java:512)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.destroySingletons(DefaultListableBeanFactory.java:1082)
at org.springframework.context.support.AbstractApplicationContext.destroyBeans(AbstractApplicationContext.java:1061)
at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:1030)
at org.springframework.context.support.AbstractApplicationContext$1.run(AbstractApplicationContext.java:949)
11:10:30.038 logback [xxl-job, executor JobLogFileCleanThread] INFO c.x.j.c.thread.JobLogFileCleanThread - >>>>>>>>>>> xxl-job, executor JobLogFileCleanThread thread destory.
11:10:30.038 logback [xxl-job, executor TriggerCallbackThread] INFO c.x.j.c.thread.TriggerCallbackThread - >>>>>>>>>>> xxl-job, executor callback thread destory.
11:10:30.038 logback [Thread-80] INFO c.x.j.c.thread.TriggerCallbackThread - >>>>>>>>>>> xxl-job, executor retry callback thread destory.
