之前更新过一次ssh项目的代码，对TOMCAT重新部署的时候却发现死活也部署不上，查看了tomcat的catalina的输出日志，然而却只有同样的一个错误提示
18-Jul-2017 18:09:18.069 INFO [16] org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading Illegal access: this web application instance has been stopped already. Could not load [com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
java.lang.IllegalStateException: Illegal access: this web application instance has been stopped already. Could not load [com.mchange.v2.resourcepool.BasicResourcePool$1DestroyResourceTask]. The following stack trace is thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access.
at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForResourceLoading(WebappClassLoaderBase.java:1305)
at org.apache.catalina.loader.WebappClassLoaderBase.checkStateForClassLoading(WebappClassLoaderBase.java:1293)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1158)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1119)
at com.mchange.v2.resourcepool.BasicResourcePool.destroyResource(BasicResourcePool.java:1040)
at com.mchange.v2.resourcepool.BasicResourcePool.removeResource(BasicResourcePool.java:1507)
at com.mchange.v2.resourcepool.BasicResourcePool.removeResource(BasicResourcePool.java:1477)
at com.mchange.v2.resourcepool.BasicResourcePool.cullExpired(BasicResourcePool.java:1565)
at com.mchange.v2.resourcepool.BasicResourcePool.access$1900(BasicResourcePool.java:44)
at com.mchange.v2.resourcepool.BasicResourcePool$CullTask.run(BasicResourcePool.java:2089)
at java.util.TimerThread.mainLoop(Timer.java:555)
at java.util.TimerThread.run(Timer.java:505)
18-Jul-2017 18:09:19.327 INFO [main] org.apache.catalina.core.StandardServer.await A valid shutdown command was received via the shutdown port. Stopping the Server instance.
然而上网翻了半天却没有一个完全的解释，都是从一个地方复制过来的答案“线程被提前关闭”，完。
完全没有一点建设性用途。
不过tomcat日志给出的错误信息完全不能用来debug，所以需要别的途径获得真实的错误信息。
所以需要用到Logger(java.util.logging.Logger)
#配置输出方式，文件输出和控制台输出
handlers = org.apache.juli.FileHandler, java.util.logging.ConsoleHandler
#配置文件输出的级别为FINE，输出目录为tomcat目录下的logs/tomcat.log目录下，前缀为error-debug
org.apache.juli.FileHandler.level = FINE
org.apache.juli.FileHandler.directory = ${catalina.home}/logs/tomcat.log
org.apache.juli.FileHandler.prefix = error-debug.
#配置控制台输出
java.util.logging.ConsoleHandler.level = FINE
java.util.logging.ConsoleHandler.formatter = java.util.logging.SimpleFormatter
日志输出级别：
SEVERE > WARNING > INFO > CONFIG > FINE > FINER > FINEST（内容最多）
将内容写入WEB-INF的class目录下，文件名为logging.properties
重启tomcat就可以看到日志内容。
18-Jul-2017 19:05:02.756 SEVERE [localhost-startStop-1] org.apache.catalina.core.StandardContext.listenerStart Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'commentDao': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [beans.xml]: Invocation of init method failed; nested exception is org.hibernate.InstantiationException: could not instantiate test objectcn.fight.waibao.model.Logistics
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessPropertyValues(CommonAnnotationBeanPostProcessor.java:306)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1106)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:913)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:385)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:284)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4754)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5216)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:752)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:728)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1107)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1841)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:748)
```
从我的日志看来就是找不到某个class导致的启动失败，然而这种错误信息竟然不会显示到catalina的日志里吗。。。