問題一
Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
2017-11-06 15:52:21.964 ERROR 49864 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter :
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APPLICATION FAILED TO START
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Description:
Cannot determine embedded database driver class for database type NONE
Action:
If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active).
原因：
spring boot默認會加載org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration類，DataSourceAutoConfiguration類使用了@Configuration注解向spring注入了dataSource bean。因為工程中沒有關於dataSource相關的配置信息，當spring創建dataSource bean因缺少相關的信息就會報錯。
解決方法：
在Application類上增加@EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class}) 或者 配置dataSource
問題二
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Mon Nov 06 16:40:38 CST 2017
There was an unexpected error (type=Not Found, status=404).
No message available
原因：
Application啟動類放的位置不對，要將Application放在最外層，也就是要包含所有子包。springboot會自動加載啟動類所在包下及其子包下的所有組件。