数据库连接失败 AreaDao.xml 配置有问题吗？检查了没发现哪里有异样

Whitelabel Error Page

This application has no explicit mapping for /error, so you are seeing this as a fallback.

Mon May 21 11:50:15 CST 2018

There was an unexpected error (type=Internal Server Error, status=500).

nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: Connections could not be acquired from the underlying database! ### The error may exist in file [/Users/zhouxuming/javaee/demo/target/classes/mapper/AreaDao.xml] ### The error may involve com.example.demo.dao.AreaDao.queryArea ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Failed to obtain JDBC Connection; nested exception is java.sql.SQLException: Connections could not be acquired from the underlying database!