这是项目上出现的问题，出现的原因是我在后台加了一个解决跨域问题的类，该类继承了WebMvcConfigurationSupport ，导致swagger的映射失效。

解决办法：

1.关闭跨域类

2.在跨域的这个类中添加：

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

总览：

@Configuration
public class CorsConfig extends WebMvcConfigurationSupport {

    /*
     * 这里主要为了解决跨域问题,所以重写addCorsMappings方法
     */
    @Override
    protected void addCorsMappings(CorsRegistry registry) {
        registry.addMapping("/**")
                .allowedOrigins("*")
                .allowedMethods("GET", "HEAD", "POST", "PUT", "DELETE", "OPTIONS")
                .allowedHeaders("*")
                .exposedHeaders("access-control-allow-headers",
                        "access-control-allow-methods",
                        "access-control-allow-origin",
                        "access-control-max-age",
                        "X-Frame-Options")
                .allowCredentials(false).maxAge(3600);
        super.addCorsMappings(registry);
    }

//解决swagger映射

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


}