springmvc搭建环境时报No mapping found for HTTP request with URI [/exam3/welcome] in DispatcherServlet with name 'spring2'

项目是使用spring MVC

（1）在浏览器中访问，后台总报错：

1. 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：

1. <?xml version="1.0" encoding="UTF-8"?>
2. <beans xmlns="http://www.springframework.org/schema/beans"
3. xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
4. xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
5. xmlns:mvc="http://www.springframework.org/schema/mvc"
6. xsi:schemaLocation="http://www.springframework.org/schema/beans
7. http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
8. http://www.springframework.org/schema/context
9. http://www.springframework.org/schema/context/spring-context-3.2.xsd
10. http://www.springframework.org/schema/aop
11. http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
12. http://www.springframework.org/schema/tx
13. http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
14. http://www.springframework.org/schema/mvc
15. http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd"
16. >
17. <!-- HandlerMapping -->
18. <bean
19. class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping" />
20. <!-- HandlerAdapter -->
21. <bean
22. class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter" />
23. <!-- ViewResolver -->
24. <bean
25. class="org.springframework.web.servlet.view.InternalResourceViewResolver">
26. <property name="viewClass"
27. value="org.springframework.web.servlet.view.JstlView" />
28. <property name="prefix" value="/WEB-INF/jsp/" />
29. <property name="suffix" value=".jsp" />
30. </bean>
31. <mvc:annotation-driven />
32. <!-- 处理器 -->
33. <!-- <bean name="/hello" class="com.mvc.jn.controller.HelloWorldController"/> -->
34. <context:component-scan base-package="com"/>
35. </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：

1. <servlet>
2. <servlet-name>spring2</servlet-name>
3. <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
4. <load-on-startup>1</load-on-startup>
5. </servlet>
6. <servlet-mapping>
7. <servlet-name>spring2</servlet-name>
8. <url-pattern>/*</url-pattern>
9. </servlet-mapping>

解决方法：把url-pattern 由/* 改为/