Could not get JDBC Connection; nested exception is java.sql.SQLException: ${jdbc.driver}

在一个SSM分布式项目中一个服务报错：

### Error querying database.  Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: ${jdbc.driver}
### The error may exist in com/pinyougou/mapper/TbGoodsMapper.xml
### The error may involve com.pinyougou.mapper.TbGoodsMapper.selectByPrimaryKey
### The error occurred while executing a query
### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: ${jdbc.driver}
    at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:)
    at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:)
    at java.lang.reflect.Method.invoke(Method.java:)
    at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:)
    ...  more

获取不到数据池连接，其他service都好好的。最后发现是数据库配置文件没有读取的原因

<!-- 加载配置文件 -->
    <context:property-placeholder location="classpath*:properties/*.properties" />