也许是由于版本的原因，把SpringBoot2的改为了SpringBoot1.5,发现在swagger这个接口文档突然不能用了。出现了下面的错误

Unable to infer base url. This is common when using dynamic servlet registration or when the API is behind an API Gateway. The base url is the root of where all the swagger resources are served. For e.g. if the api is available at http://example.org/api/v2/api-docs then the base url is http://example.org/api/. Please enter the location manually:

解决办法：
在ApiApplication里面添加@EnableSwagger2