先看一下问题：
1.在web.xml中配置Spring 加载Spring mvc的时候配置如下：
<!--配置SpringMVC的前端控制器-->
<servlet>
<servlet-name>DispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>DispatcherServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
2.在spring-mvc.xml中配置如下：
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.alibaba.com/schema/stat"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.alibaba.com/schema/stat http://www.alibaba.com/schema/stat.xsd">
<!--Controller的组件扫描-->
<context:component-scan base-package="com.lxl">
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<!--配置内部资源视图解析器-->
<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!-- /jsp/success.jsp -->
<property name="prefix" value="/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
</beans>
看似一切正常。。。
那么启动就报错：问题如下：
org.springframework.beans.factory.BeanDefinitionStoreException: Failed to parse configuration class [com.lxl.Controller.UserController]; nested exception is java.io.FileNotFoundException: class path resource [com/lxl/Controller/UserController.class] cannot be opened because it does not exist at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:184) at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:316) at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:233) at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:273) at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:93) at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:694) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:532) at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:672) at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:638) at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:686) at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:554) at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:499) at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:172) at javax.servlet.GenericServlet.init(GenericServlet.java:158) at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1144) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1091) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:983) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4956) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5270) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:754) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:730) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:734) at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1731) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:564) at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:287) at java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:809) at java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:483) at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:432) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:564) at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:287) at java.management/com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:809) at java.management/com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1466) at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:75) at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1307) at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1399) at java.management.rmi/javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:827) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:564) at java.rmi/sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:359) at java.rmi/sun.rmi.transport.Transport$1.run(Transport.java:200) at java.rmi/sun.rmi.transport.Transport$1.run(Transport.java:197) at java.base/java.security.AccessController.doPrivileged(Native Method) at java.rmi/sun.rmi.transport.Transport.serviceCall(Transport.java:196) at java.rmi/sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:567) at java.rmi/sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:800) at java.rmi/sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:682) at java.base/java.security.AccessController.doPrivileged(Native Method) at java.rmi/sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:681) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641) at java.base/java.lang.Thread.run(Thread.java:844)
挺简单的一个exception，没有找到Controller。反复查找XML配置。查找IEDA设置。查找pom，查找*****
好像都对。。。
然后发现Controller包名大写了。啊啊啊啊***
改成小写，一路测试通过。。