spring boot项目中包的组织

NlpApplication是包含main函数的一个类，如果这个类放错位置会报

Whitelabel Error Page This application has no explicit mapping for /error, so you are seeing this as a fallback. Tue Jun 30 17:24:02 CST 2015 There was an unexpected error (type=Not Found, status=404). No message available

这是stackoverflow上的一个例子：

com
   +- APP
         +- Application.java  <--- your main class should be here, above your controller classes
         |
         +- model
         |   +- user.java
         +- controller
             +- UserController.java

总之，包含main的类应该放在什么模型什么控制器所在包的外层。