报错信息如下：
Failed to configure a DataSource: ‘url’ attribute is not specified and no embedded datasource could be configured.

Reason: Failed to determine a suitable driver class

Action:

Consider the following:
If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are curr

这是因为加载不到数据库配置文件
也不是加载不到，是压根没有
因为你打包的时候没有把resource下的文件打进去。

解决方法：
在pom里增加打包的信息

<!--设置对应生成的xml文件路径??-->
<resources>
    <resource>
        <directory>src/main/java</directory>
        <includes>
            <include>**/*.xml</include>
        </includes>
    </resource>
    <!--设置自己目录下的配置文件-->
    <resource>
      <!--下方resources的文件夹名字要和自己项目的文件夹名确认一致才行 很多人就是忽略了名字不一致 -->
        <directory>src/main/resources</directory>
        <includes>
            <include>**/*</include>
        </includes>
    </resource>
</resources>

初学springboot的同学，千万要小心