今天在整合spring和mybatis时出现No qualifying bean of type [com.studyplan.dao.UserDao] found for dependency,dao无法注入问题,web.xml文件如下


<!DOCTYPE web-app PUBLIC

 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"

 "http://java.sun.com/dtd/web-app_2_3.dtd" >


<web-app>

  <display-name>Archetype Created Web Application</display-name>

  <!-- Spring和mybatis的配置文件 -->  

  <context-param>  

      <param-name>contextConfigLocation</param-name>  

      <param-value>/WEB-INF/configs/spring/spring-mybatis.xml</param-value>  

  </context-param>  

  <servlet>

    <servlet-name>mvc-dispatcher</servlet-name>

    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

    <init-param>

      <param-name>contextConfigLocation</param-name>

      <param-value>/WEB-INF/configs/spring/mvc-dispatcher-servlet.xml</param-value>

    </init-param>

    <load-on-startup>1</load-on-startup>

  </servlet>


  <servlet-mapping>

    <servlet-name>mvc-dispatcher</servlet-name>

    <url-pattern>/</url-pattern>

  </servlet-mapping>

</web-app>


因为mvc-dispatcher-servlet.xml为<load-on-startup>1</load-on-startup>所以该servlet的执行顺序较高,spring-mybatis.xml的执行顺序较低,spring-mybatis.xml和mvc-dispatcher-servlet.xml的内容如下


mvc-dispatcher-servlet.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"

       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.xsd"

>

<context:annotation-config />

<!-- 自动扫描 -->  

<context:component-scan base-package="com.studyplan" />

<!--

<context:component-scan base-package="com.studyplan.controller">

<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>

</context:component-scan>

<context:component-scan base-package="com.studyplan.service">

<context:include-filter type="annotation" expression="org.springframework.stereotype.Service"/>

</context:component-scan>

-->

<mvc:annotation-driven />

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">

<property name="prefix" value="/views/" />

<property name="suffix" value=".jsp" />

</bean>



</beans>


spring-mybatis.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:p="http://www.springframework.org/schema/p"  

    xmlns:context="http://www.springframework.org/schema/context"  

    xmlns:mvc="http://www.springframework.org/schema/mvc"  

    xsi:schemaLocation="http://www.springframework.org/schema/beans    

                        http://www.springframework.org/schema/beans/spring-beans-3.1.xsd    

                        http://www.springframework.org/schema/context    

                        http://www.springframework.org/schema/context/spring-context-3.1.xsd    

                        http://www.springframework.org/schema/mvc    

                        http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">  

    <!-- 自动扫描 -->  

    <context:component-scan base-package="com.studyplan.dao" />  

    <!-- 引入配置文件 -->  

    <bean id="propertyConfigurer"  

        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">  

        <property name="location" value="classpath:jdbc.properties" />  

    </bean>  

  

    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"  

        destroy-method="close">  

        <property name="driverClassName" value="${driver}" />  

        <property name="url" value="${url}" />  

        <property name="username" value="${username}" />  

        <property name="password" value="${password}" />  

        <!-- 初始化连接大小 -->  

        <property name="initialSize" value="${initialSize}"></property>  

        <!-- 连接池最大数量 -->  

        <property name="maxActive" value="${maxActive}"></property>  

        <!-- 连接池最大空闲 -->  

        <property name="maxIdle" value="${maxIdle}"></property>  

        <!-- 连接池最小空闲 -->  

        <property name="minIdle" value="${minIdle}"></property>  

        <!-- 获取连接最大等待时间 -->  

        <property name="maxWait" value="${maxWait}"></property>  

    </bean>  

  

    <!-- spring和MyBatis完美整合,不需要mybatis的配置映射文件 -->  

    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">  

        <property name="dataSource" ref="dataSource" />  

        <!-- 自动扫描mapping.xml文件 -->  

        <property name="mapperLocations" value="classpath*:com/studyplan/mapping/*.xml"></property>  

    </bean>  

  

    <!-- DAO接口所在包名,Spring会自动查找其下的类 -->  

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">  

        <property name="basePackage" value="com.studyplan.dao" />  

        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>  

    </bean>  

  

    <!-- (事务管理)transaction manager, use JtaTransactionManager for global tx -->  

    <bean id="transactionManager"  

        class="org.springframework.jdbc.datasource.DataSourceTransactionManager">  

        <property name="dataSource" ref="dataSource" />  

    </bean>  

  

</beans>  


spring-mybatis.xml中定义的有关于dao的定义,但是由于他的优先级较低,所以在spring进行注入的时候并没有读取这个xml文件,导致了dao层无法注入



解决方案如下

将spring-mybatis.xml更名为mvc-spring-mybatis.xml,将web.xml修改为一下的格式

<!DOCTYPE web-app PUBLIC

 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"

 "http://java.sun.com/dtd/web-app_2_3.dtd" >


<web-app>

  <display-name>Archetype Created Web Application</display-name>

  <!-- Spring和mybatis的配置文件 -->  

  <servlet>

    <servlet-name>mvc-dispatcher</servlet-name>

    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

    <init-param>

      <param-name>contextConfigLocation</param-name>

      <param-value>/WEB-INF/configs/spring/mvc*.xml</param-value>

    </init-param>

    <load-on-startup>1</load-on-startup>

  </servlet>


  <servlet-mapping>

    <servlet-name>mvc-dispatcher</servlet-name>

    <url-pattern>/</url-pattern>

  </servlet-mapping>

</web-app>

这样这两个配置文件就会一起读进来