Whitelabel Error Page原因及解决方案

解决方案一：

目录结构问题：

官网说明：http://docs.spring.io/spring-boot/docs/current-SNAPSHOT/reference/htmlsingle/#using-boot-structuring-your-code

14.2 Locating the main application class
We generally recommend that you locate your main application class in a root package above other classes. The @EnableAutoConfiguration annotation is often placed on your main class, and it implicitly defines a base “search package” for certain items. For example, if you are writing a JPA application, the package of the @EnableAutoConfiguration annotated class will be used to search for @Entity items.
 
Using a root package also allows the @ComponentScan annotation to be used without needing to specify a basePackage attribute. You can also use the @SpringBootApplication annotation if your main class is in the root package.
 
Here is a typical layout:
 
com
 +- example
     +- myproject
         +- Application.java
         |
         +- domain
         |   +- Customer.java
         |   +- CustomerRepository.java
         |
         +- service
         |   +- CustomerService.java
         |
         +- web
             +- CustomerController.java

将Application.java移动至com.xxxx下即可（与controller,mapper,service等包平级）。

解决方案二:

方法返回值问题

当你返回的不是模板，而是字符串时，Controller类需要添加 注解 @RestController.

代码示例：

@RestController
public class MyController {
    @ResponseBody
    @RequestMapping("show")
    public String show(){
        return "hello SpringBoot";
    }
}