1 直接实现WebMvcConfigurer （官方推荐）
例如：
@Configuration
public class WebMvcConfg implements WebMvcConfigurer {
//todo
}2 直接继承WebMvcConfigurationSupport
例如：
@Configuration
public class WebMvcConfg extends WebMvcConfigurationSupport {
//todo
}今天查了下官方api
Deprecated.
as of 5.0 WebMvcConfigurer has default methods (made possible by a Java 8 baseline) and can be implemented directly without the need for this adapter
An implementation of WebMvcConfigurer with empty methods allowing subclasses to override only the methods they’re interested in.
因此推荐第一种方式