<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> 
    <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    <property name="url" value="xxxx" />
    <property name="username"><value>xxxx</value></property>
        <property name="password"><value>xxxxx</value></property>
        <property name="maxActive"><value>20</value></property>
        <property name="initialSize"><value>1</value></property>
        <property name="maxWait"><value>60000</value></property>
        <property name="maxIdle"><value>20</value></property>
        <property name="minIdle"><value>3</value></property>
        <property name="removeAbandoned"><value>true</value></property>
        <property name="removeAbandonedTimeout"><value>180</value></property>
        <property name="connectionProperties"><value>clientEncoding=GBK</value></property>
</bean>

------解决方案--------------------

C3P0的

XML code
<props>
    <prop key="acquireIncrement">1</prop>
    <prop key="initialPoolSize">1</prop>
    <prop key="minPoolSize">1</prop>
    <prop key="maxPoolSize">16</prop>
    <prop key="maxIdleTime">1800</prop>
    <prop key="maxIdleTimeExcessConnections">1000</prop> <!-- 自动收缩连接用的,单位秒-->
    <!-- 自动重连需要的三个参数  -->
    <prop key="acquireRetryAttempts">30</prop>
        <prop key="acquireRetryDelay">1000</prop>
        <prop key="breakAfterAcquireFailure">false</prop>
</props>