org.springframework.dao.Recovera

exception:org.springframework.dao.RecoverableDataAccessException:

Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 262,050 milliseconds ago. The last packet sent successfully to the server was 262,053 milliseconds ago.

本次 是因为获取数据库连接的时候获取到无效的连接导致该异常。
解决方式：
设置数据源该属性
<property name="validationQuery" value="SELECT 1"/>
<property name="testOnBorrow" value="true"/>