解决Mybatis连接Sql server 出现 Cannot load JDBC driver class 'com.mysql.jdbc.Driver '的问题

tomcat启动的时候没有错误，但是进行数据库操作就会有错误。

在网上找了很久  好不容易找到解决方法

转自 http://blog.csdn.net/ro_bot/article/details/51659502

出现以上错误原因是：数据源的错误配置：

错误的jdbc.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/seckill
username=root
password=root

错误的spring.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"
  xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
  <context:property-placeholder location="jdbc.properties"/>
  <bean id="dataSource" destroy-method="close" class="org.apache.commons.dbcp.BasicDataSource" >
        <property name="driverClass" value="${driver}"/>
        <property name="url" value="${url}" />
        <property name="username" value="${username}" />
        <property name="password" value="${password}" />
 </beans>

将配置修改为：

jdbc.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/seckill
jdbc.username=root
jdbc.password=root

spring-dao.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"
  xsi:schemaLocation="
    http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.0.xsd">
  <context:property-placeholder location="jdbc.properties"/>
  <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClass" value="${jdbc.driver}"/>
    <property name="url" value="${jdbc.url}"/>
    <property name="username" value="${jdbc.username}"/>
    <property name="password" value="${jdbc.password}"/>
  </bean>
</beans>

配置完后成功运行。