用的IDEA，之前写测试类的时候就踩了坑，还好坑比较小跳出来了，这次这个真的看了好多同学提问和老师的解答都de不出来…

跟着代码敲的，然而loaclhost:8080/o2o/superadmin/listarea发生404了…然后把o2o去掉以后，就是直接访问localhost:8080/superadmin/listarea出现下面信息：

{"success":false,"errMsg":"org.mybatis.spring.MyBatisSystemException: 
nested exception is org.apache.ibatis.exceptions.
PersistenceException: \r\n### Error querying database.  
Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: 
Could not get JDBC Connection; nested exception is java.sql.SQLException: 
Connections could not be acquired from the underlying database!\r\n### 
The error may exist in file [R:\\mooc\\o2o\\target\\o2o\\WEB-INF\\classes\\mapper\\AreaDao.xml]\r\n### 
The error may involve dto.AreaDao.queryArea\r\n### 
The error occurred while executing a query\r\n### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: 
Could not get JDBC Connection; nested exception is java.sql.SQLException: 
Connections could not be acquired from the underlying database!"}

我记得之前调试测试类的时候有一个警告是说jdbc的驱动没有导入成功，不知道有没有影响…
下面附上代码，辛苦老师解答了…
ps. 有些base-package和老师的不太一样是因为我idea的目录结构导致的，写的时候能通过idea的自动匹配功能匹配出选项来…

Controller

@Controller
@RequestMapping("/superadmin")
public class AreaController {
    @Autowired
    private AreaService areaService;

    @RequestMapping(value="/listarea", method = RequestMethod.GET)
    @ResponseBody
    private Map<String, Object> listArea() {
        Map<String, Object> modelMap = new HashMap<String, Object>();
        List<Area> list = new ArrayList<Area>();
        try {
            list = areaService.getAreaList();
            modelMap.put("rows", list);
            modelMap.put("total", list.size());
        } catch (Exception e) {
            e.printStackTrace();
            modelMap.put("success", false);
            modelMap.put("errMsg", e.toString());
        }

        return modelMap;
    }
}

web-xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">
    <display-name>Archetype Created Web Application</display-name>

    <servlet>
        <servlet-name>spring-dispatcher</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring/spring-*.xml</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>spring-dispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

jdbc.properties

jdbc.driver=com.mysql.Driver
jdbc.url=jdbc:mysql://localhost:3306/o2o?useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=SlamDunk1011

spring-web.xml

<?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.springframework.org/schema/mvc"
    xmlns:aop="http://www.springframework.org/schema/aop"
    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.springframework.org/schema/mvc
	    http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">

    <!-- 扩充了注解驱动，可以将参数绑定到控制器参数 -->
    <mvc:annotation-driven/>

    <!-- 静态资源的处理，css,js,img... -->
    <mvc:resources mapping="/resources/**" location="/resources/"/>
    <mvc:default-servlet-handler />
    <!-- ViewResolver:视图解析器。可以配置多个 但是一定要将这个ViewResolver(InternalResourceViewResolver)
        放到最后 -->
    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/html/" />
        <property name="suffix" value=".html" />
    </bean>
    <context:component-scan base-package="web" />
</beans>