spring文件无法解析占位符,按照字符串解析

今天用了spring的占位符来配置mybatis的dataSource

<bean id="sourcePropertyConfigurer"
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="locations">
      <list>
        <value>classpath:*.properties</value>
      </list>
    </property>
  </bean>

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="${sqlserver.jdbc.driver}" />
    <property name="url" value="${sqlserver.url}" />
    <property name="username" value="${sqlserver.username}" />
    <property name="password" value="${sqlserver.password}" />
    <property name="timeBetweenEvictionRunsMillis" value="120000"/>
    <property name="minEvictableIdleTimeMillis" value="180000"/>
    <property name="numTestsPerEvictionRun" value="20"/>
    <property name="maxActive" value="20"/>
    <property name="maxIdle" value="5"/>
    <property name="minIdle" value="2"/>
    <property name="maxWait" value="1500"/>
    <property name="removeAbandoned" value="true"/>
    <property name="removeAbandonedTimeout" value="20"/>
  </bean>

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"
    p:dataSource-ref="dataSource" p:configLocation="classpath:META-INF/spring/mybatisConfig.xml"
    p:mapperLocations="classpath:META-INF/mybatis/mapper/*Mapper.xml" />  

  <bean class="org.mybatis.spring.SqlSessionTemplate">
    <constructor-arg ref="sqlSessionFactory" />
  </bean>

  <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
    p:sqlSessionFactory-ref="sqlSessionFactory" p:basePackage="*********.dal.mapper" /> //Mapper.java文件所在目录

然后tomcat启动报的错误是:Caused by: java.lang.ClassNotFoundException: ${sqlserver.jdbc.driver}  说明根本就没有去配置文件中去获取sqlserver.jdbc.driver的值,而是直接把${sqlserver.jdbc.driver} 当字符串去获取类驱动了,所以报错

主要错误原因是

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
    p:sqlSessionFactory-ref="sqlSessionFactory" p:basePackage="***********.dal.mapper" />

在org.mybatis.spring.mapper.MapperScannerConfigurer配置中增加了属性sqlSessionFactory,把sqlSessionFactory去掉即可,及改为

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
    p:basePackage="***********.dal.mapper" />