项目是使用spring MVC
（1）在浏览器中访问，后台总报错：
- No mapping found for HTTP request with URI [/exam3/welcome] in DispatcherServlet with name 'spring2'
查了好半天，才发现是controller 没有扫描到。
我是使用的注解。
spring mvc配置文件如下：
- <?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
- xmlns:mvc="http://www.springframework.org/schema/mvc"
- xsi:schemaLocation="http://www.springframework.org/schema/beans
- http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
- http://www.springframework.org/schema/context
- http://www.springframework.org/schema/context/spring-context-3.2.xsd
- http://www.springframework.org/schema/aop
- http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
- http://www.springframework.org/schema/tx
- http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
- http://www.springframework.org/schema/mvc
- http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd"
- >
- <!-- HandlerMapping -->
- <bean
- class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping" />
- <!-- HandlerAdapter -->
- <bean
- class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter" />
- <!-- ViewResolver -->
- <bean
- class="org.springframework.web.servlet.view.InternalResourceViewResolver">
- <property name="viewClass"
- value="org.springframework.web.servlet.view.JstlView" />
- <property name="prefix" value="/WEB-INF/jsp/" />
- <property name="suffix" value=".jsp" />
- </bean>
- <mvc:annotation-driven />
- <!-- 处理器 -->
- <!-- <bean name="/hello" class="com.mvc.jn.controller.HelloWorldController"/> -->
- <context:component-scan base-package="com"/>
- </beans>
controller 的目录结构如下：
（2）这个问题解决之后，又报错：
No mapping found for HTTP request with URI [/exam3/WEB-INF/jsp/welcome.jsp] in DispatcherServlet with name 'spring2'
结果发现是web.xml配置得有问题，下面是有问题的：
- <servlet>
- <servlet-name>spring2</servlet-name>
- <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
- <load-on-startup>1</load-on-startup>
- </servlet>
- <servlet-mapping>
- <servlet-name>spring2</servlet-name>
- <url-pattern>/*</url-pattern>
- </servlet-mapping>
解决方法：把url-pattern 由/* 改为/