spring-mvc项目
下午在公司写一个调微信接口的utils，一直写，也没有重启服务，只是用main测试，晚上回到家，坑了
tomcat突然起不来了，报错如下，从10点搞到2点，去了趟洗手间，然后想明白了
根据log提示，就是缺少包吗，少了core包，我勒个擦
可是，加了包，升级core版本，都不行
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#0': Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: org/springframework/core/MethodIntrospector
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:755)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1269)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1182)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1072)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5368)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5660)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:899)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:875)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:652)
at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:1092)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1984)
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:745)
Caused by: java.lang.NoClassDefFoundError: org/springframework/core/MethodIntrospector
原因是啥，是啥，是啥
原因是，在我使用了网上copy的代码时，idea会自动加载一些依赖，比如因为使用个什么什么（后来删了，我也忘了是啥），pom.xml文件中就引入了如下的依赖
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>4.3.6.RELEASE</version>
</dependency>
时这个依赖，与spring-mvc别的核心依赖冲突了，导致加载spring核心类的失败。
一定要小心呀，白白浪费4小时，现在都快夜里3点了，刚解决完，老子还在写博客。睡觉吧