springboot 中集成 knife4j 时，报错 No mapping for GET /pdm/doc.html

原因是项目中其他配置类继承了 WebMvcConfigurationSupport；这会导致 swagger 配置失效，将继承 WebMvcConfigurationSupport 类相关代码放在 swagger 配置类中可解决问题

springboot版本：

<parent>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-parent</artifactId>
   <version>2.1.12.RELEASE</version>
   <relativePath/> <!-- lookup parent from repository -->
</parent>

knife4j版本：

<dependency>
   <groupId>com.github.xiaoymin</groupId>
   <artifactId>knife4j-spring-boot-starter</artifactId>
   <version>2.0.1</version>
   <exclusions>
      <exclusion>
         <artifactId>guava</artifactId>
         <groupId>com.google.guava</groupId>
      </exclusion>
   </exclusions>
</dependency>

swagger配置：

@Override
public void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/**").addResourceLocations(
            "classpath:/static/");
    registry.addResourceHandler("doc.html").addResourceLocations(
            "classpath:/META-INF/resources/");
    registry.addResourceHandler("/webjars/**").addResourceLocations(
            "classpath:/META-INF/resources/webjars/");
}