spring下配置tomcat jdbc pool 报找不到"com.mysql.jdbc.Driver"类

初始配置

<!--tomcat jdbc pool数据源配置-->
<bean id="dataSource" class="org.apache.tomcat.jdbc.pool.DataSource" destroy-method="close">
<property name="poolProperties">
<bean class="org.apache.tomcat.jdbc.pool.PoolProperties">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="${database.url}"/>
<property name="username" value="${database.username}"/>
<property name="password" value="${database.password}"/>
<property name="jmxEnabled" value="true"/>
<property name="testWhileIdle" value="true"/>
<property name="testOnBorrow" value="true"/>
<property name="testOnReturn" value="false"/>
<property name="validationInterval" value="30000"/>
<property name="validationQuery" value="SELECT 1"/>
<property name="timeBetweenEvictionRunsMillis" value="30000"/>
<property name="initialSize" value="10"/>
<property name="maxActive" value="40"/>
<property name="minIdle" value="10"/>
<property name="maxIdle" value="20"/>
<property name="maxWait" value="10000"/>
<property name="minEvictableIdleTimeMillis" value="30000"/>
<property name="logAbandoned" value="false"/>
<property name="removeAbandoned" value="true"/>
<property name="removeAbandonedTimeout" value="60"/>
<property name="jdbcInterceptors" value="org.apache.tomcat.jdbc.pool.interceptor.ConnectionState;org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer"/>
</bean>
</property>
</bean>

<!-- 定义实体管理器工厂 -->
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="persistenceUnitName" value="myJPA" />
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="showSql" value="true"/>
<property name="databasePlatform" value="org.hibernate.dialect.MySQL5Dialect"/>
<property name="generateDdl" value="true" />
<property name="database" value="MYSQL" />
</bean>
</property>
<property name="persistenceProviderClass" value="org.hibernate.jpa.HibernatePersistenceProvider"/>
<property name="jpaProperties">
<props>
<prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>
<prop key="hibernate.dialect">org.hibernate.dialect.MySQL5Dialect</prop>
<prop key="hibernate.connection.driver_class">com.mysql.jdbc.Driver</prop>
<prop key="hibernate.connection.url">${database.url}</prop>
<prop key="hibernate.connection.username">${database.username}</prop>
<prop key="hibernate.connection.password">${database.password}</prop>
<prop key="hibernate.max_fetch_depth">3</prop>
<prop key="hibernate.jdbc.fetch_size">18</prop>
<prop key="hibernate.jdbc.batch_size">10</prop>
<prop key="hibernate.hbm2ddl.auto">update</prop>
<prop key="hibernate.show_sql">true</prop>
<prop key="hibernate.format_sql">true</prop>
<prop key="javax.persistence.validation.mode">none</prop>
</props>
</property>
</bean>

启动时报错,

...

java.sql.SQLException: com.mysql.jdbc.Driver
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:254) ~[tomcat-jdbc.jar:na]
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:182) ~[tomcat-jdbc.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:702) ~[tomcat-jdbc.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:634) ~[tomcat-jdbc.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:488) ~[tomcat-jdbc.jar:na]
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:144) ~[tomcat-jdbc.jar:na]

...

at javax.management.remote.rmi.RMIConnectionImpl.access$300(Unknown Source) [na:1.8.0]
at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(Unknown Source) [na:1.8.0]
at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(Unknown Source) [na:1.8.0]
at javax.management.remote.rmi.RMIConnectionImpl.invoke(Unknown Source) [na:1.8.0]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:201402101544]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:201402101544]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:201402101544]
at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0]
at sun.rmi.server.UnicastServerRef.dispatch(Unknown Source) [na:1.8.0]
at sun.rmi.transport.Transport$1.run(Unknown Source) [na:1.8.0]
at sun.rmi.transport.Transport$1.run(Unknown Source) [na:1.8.0]
at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0]
at sun.rmi.transport.Transport.serviceCall(Unknown Source) [na:1.8.0]
at sun.rmi.transport.tcp.TCPTransport.handleMessages(Unknown Source) [na:1.8.0]
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(Unknown Source) [na:1.8.0]
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(Unknown Source) [na:1.8.0]
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [na:1.8.0]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [na:1.8.0]
at java.lang.Thread.run(Unknown Source) [na:1.8.0]
Caused by: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader$1.run(Unknown Source) ~[na:1.8.0]
at java.net.URLClassLoader$1.run(Unknown Source) ~[na:1.8.0]
at java.security.AccessController.doPrivileged(Native Method) [na:1.8.0]
at java.net.URLClassLoader.findClass(Unknown Source) ~[na:1.8.0]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[na:1.8.0]
at java.lang.ClassLoader.loadClass(Unknown Source) ~[na:1.8.0]

这篇文章解释了原因 http://stackoverflow.com/questions/4790589/sqlexception-w-tomcat-7-0-jdbc-connection-pool-and-mysql , 大概意思是加载 数据库连接驱动jar包(tomcat?) 和 tomcat jdbc包(spring?) 不是同一个Classloader, 所以需要改为如下配置

<!--  使用spring 加载jdbc驱动  -->
<bean id="dataSourceTemplate" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${database.driver}" />
<property name="url" value="${database.url}" />
<property name="username" value="${database.username}" />
<property name="password" value="${database.password}" />
</bean>

<!--tomcat jdbc pool数据源配置-->
<bean id="dataSource" class="org.apache.tomcat.jdbc.pool.DataSource" destroy-method="close">
<!--  通过引用加载数据库信息  -->
<property name="dataSource" ref="dataSourceTemplate"/>

<property name="jmxEnabled" value="true"/>
<property name="testWhileIdle" value="true"/>
<property name="testOnBorrow" value="true"/>
<property name="testOnReturn" value="false"/>
<property name="validationInterval" value="30000"/>
<property name="validationQuery" value="SELECT 1"/>
<property name="timeBetweenEvictionRunsMillis" value="30000"/>
<property name="initialSize" value="10"/>
<property name="maxActive" value="40"/>
<property name="minIdle" value="10"/>
<property name="maxIdle" value="20"/>
<property name="maxWait" value="10000"/>
<property name="minEvictableIdleTimeMillis" value="30000"/>
<property name="logAbandoned" value="false"/>
<property name="removeAbandoned" value="true"/>
<property name="removeAbandonedTimeout" value="60"/>
<property name="jdbcInterceptors" value="org.apache.tomcat.jdbc.pool.interceptor.ConnectionState;org.apache.tomcat.jdbc.pool.interceptor.StatementFinalizer"/>
</bean>

其他配置不变