最常听到的问题你该怎么答（简单记录遇到的一个问题）
最常听到的问题你该怎么答（简单记录遇到的一个问题）知道了核心问题那就开始解决吧。Couldn't retrieve job: Table 'xyz.QRTZ_JOB_DETAILS' doesn't exist ，看出是xyz库中没有QRTZ_JOB_DETAILS 这个表，于是我打开navicat，连上数据库打开xyz ，发现这个QRTZ_JOB_DETAILS是存在的，只不过是小写，不是日子提示的大写。Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'quartzScheduler' defined in class path resource [o
今天发现一个错误，简单记录一下，运行一个项目，之前运行没有问题，但是今天在启动的时候确一直启动不了。
首先说明一下这是一个Spring boot 集成quartz做任务调度的项目，版本信息就不贴了，因为和本文没有什么关系。
错误信息如下：
2019-09-05 09:56:23.993 WARN [web-scheduler-localhost ] 5324 --- [ender@21a0676f}] s.c.a.AnnotationConfigApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'eurekaRibbonClientConfiguration': Unsatisfied dependency expressed through field 'clientConfig'; nested exception is org.springframework.beans.factory.BeanCreationNotAllowedException: Error creating bean with name 'eurekaClientConfigBean': Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!) 2019-09-05 09:56:23.997 INFO [web-scheduler-localhost ] 5324 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2019-09-05 09:56:24.003 WARN [web-scheduler-localhost ] 5324 --- [ost-startStop-1] o.a.c.loader.WebappClassLoaderBase : The web application [ROOT] appears to have started a thread named [RxIoScheduler-1 (Evictor)] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread: sun.misc.Unsafe.park(Native Method) java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215) java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078) java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093) java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809) java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) java.lang.Thread.run(Thread.java:745)
根据平时的看错误经验：
Error creating bean with name 'eurekaRibbonClientConfiguration': Unsatisfied dependency expressed through field 'clientConfig'; nested exception is org.springframework.beans.factory.BeanCreationNotAllowedException: Error creating bean with name 'eurekaClientConfigBean': Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)
核心的错误不就是这个吗，但事实貌似不是这样，排查代码和配置，没有发现代码和配置有任何的问题。
于是就耐心看整个启动日志的输出，发现在了下面这一句异常（控制台上 这一句异常信息和其他日志一样，没有任何突出之处）。
Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'quartzScheduler' defined in class path resource [org/springframework/boot/autoconfigure/quartz/QuartzAutoConfiguration.class]: Invocation of init method failed; nested exception is org.quartz.JobPersistenceException: Couldn't retrieve job: Table 'xyz.QRTZ_JOB_DETAILS' doesn't exist [See nested exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'xyz.QRTZ_JOB_DETAILS' doesn't exist]
从这句异常Error creating bean with name 'quartzScheduler' defined in class path resource之后发现容器开始关Quartz线程开始停止，容器也开始关闭。那分析就是这句异常导致服务不能重启的。上面的那个异常不是罪魁祸首，而是受害者。
知道了核心问题那就开始解决吧。Couldn't retrieve job: Table 'xyz.QRTZ_JOB_DETAILS' doesn't exist ，看出是xyz库中没有QRTZ_JOB_DETAILS 这个表，于是我打开navicat，连上数据库打开xyz ，发现这个QRTZ_JOB_DETAILS是存在的，只不过是小写，不是日子提示的大写。
这种情况我立马想到之前整理的过一篇文章，不是它嘛。一个因MySQL大小写敏感导致的问题
到这里 这个问题就结束了，我之所以记录这篇文章：
有一些错误，你能够通过提示就找到原因。这个错误就是罪魁祸首。
而有一些错误，它只是受害者。而真正的错误原因隐藏在另一个地方。
希望遇到类似情况的伙伴看到这篇能够有所收获
