The method's class, springfox.documentation.builders.RequestHandlerSelectors, is available from the following locations:

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APPLICATION FAILED TO START
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Description:

An attempt was made to call a method that does not exist. The attempt was made from the following location:

    com.be.common.web.configurer.SwaggerConfigurer.docket(SwaggerConfigurer.java:51)

The following method did not exist:

    springfox.documentation.builders.RequestHandlerSelectors.basePackage(Ljava/lang/String;)Lcom/google/common/base/Predicate;

The method's class, springfox.documentation.builders.RequestHandlerSelectors, is available from the following locations:

    jar:file:/Users/u/.m2/repository/io/springfox/springfox-core/3.0.0/springfox-core-3.0.0.jar!/springfox/documentation/builders/RequestHandlerSelectors.class

It was loaded from the following location:

    file:/Users/u/.m2/repository/io/springfox/springfox-core/3.0.0/springfox-core-3.0.0.jar

Action:

Correct the classpath of your application so that it contains a single, compatible version of springfox.documentation.builders.RequestHandlerSelectors

原因是可能重复配置swagger，可能是其他框架配置swagger了，只需要把框架内置的swagger配置禁用。

然后手动配置下knife4j 就可以了

package com.x.serving.core.config;

import com.x.serving.annotation.SwaggerApi;
import com.x.serving.common.constants.ServingConstants;
import com.github.xiaoymin.knife4j.spring.annotations.EnableKnife4j;
import io.swagger.annotations.ApiOperation;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import springfox.bean.validators.configuration.BeanValidatorPluginsConfiguration;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.ParameterBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.schema.ModelRef;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.ApiKey;
import springfox.documentation.service.AuthorizationScope;
import springfox.documentation.service.Contact;
import springfox.documentation.service.Parameter;
import springfox.documentation.service.SecurityReference;
import springfox.documentation.service.SecurityScheme;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spi.service.contexts.SecurityContext;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2WebMvc;

/**
 * @author x
 * @version 1.0.0
 * @email <a href="x.x@x.cn">muzhi</a>
 * @date 2022-02-14 15:19
 */
@Configuration
@EnableSwagger2WebMvc
@EnableKnife4j
@Import(BeanValidatorPluginsConfiguration.class)
public class Swagger2Configuration implements WebMvcConfigurer {
    @Override
    public void addViewControllers(final ViewControllerRegistry registry) {
        registry.addViewController("/").setViewName("doc.html");
    }

    /**
     *
     * 显示swagger-ui.html文档展示页，还必须注入swagger资源：
     *
     * @param registry
     */
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry.addResourceHandler("swagger-ui.html").addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("doc.html").addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
    }

    /**
     * swagger2的配置文件，这里可以配置swagger2的一些基本的内容，比如扫描的包等等
     *
     * @return Docket
     */
    @Bean(value = "defaultApi2")
    public Docket defaultApi2() {

        //        List<ResponseMessage> responseMessages = new ArrayList<>(2);
        //        ResponseMessage build = new ResponseMessageBuilder().code(200)
        //            .message("").responseModel(new ModelRef(Response.class.getName()))
        //            .build();
        //
        //        responseMessages.add(build);

        return new Docket(DocumentationType.SWAGGER_2)
            //            .globalResponseMessage(RequestMethod.GET, responseMessages)
            //            .globalResponseMessage(RequestMethod.POST, responseMessages)
            .apiInfo(apiInfo())
            .select()
            //此包路径下的类，才生成接口文档
            .apis(RequestHandlerSelectors.basePackage("com.be.edge.serving")
                                         .or(RequestHandlerSelectors.withClassAnnotation(SwaggerApi.class)))
            //加了ApiOperation注解的类，才生成接口文档
            .apis(RequestHandlerSelectors.withClassAnnotation(RestController.class))
            .apis(RequestHandlerSelectors.withMethodAnnotation(ApiOperation.class))
            .paths(PathSelectors.any())
            .build()
            .securitySchemes(Collections.singletonList(securityScheme()))
            .securityContexts(securityContexts());
        //.globalOperationParameters(setHeaderToken());
    }

    /***
     * oauth2配置
     * 需要增加swagger授权回调地址
     * http://localhost:8888/webjars/springfox-swagger-ui/o2c.html
     * @return
     */
    @Bean
    SecurityScheme securityScheme() {
        return new ApiKey(ServingConstants.TOKEN_NAME, ServingConstants.TOKEN_NAME, "header");
    }
    /**
     * JWT token
     * @return
     */
    private List<Parameter> setHeaderToken() {
        ParameterBuilder tokenPar = new ParameterBuilder();
        List<Parameter> pars = new ArrayList<>();
        tokenPar.name(ServingConstants.TOKEN_NAME).description(ServingConstants.TOKEN_DESCRIPTION).modelRef(new ModelRef("string")).parameterType("header").required(false).build();
        pars.add(tokenPar.build());
        return pars;
    }

    /**
     * api文档的详细信息函数,注意这里的注解引用的是哪个
     *
     * @return
     */
    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
            // //大标题
            .title("EdgeX-Lambda 后台服务API接口文档")
            // 版本号
            .version("1.0")
            //                .termsOfServiceUrl("NO terms of service")
            // 描述
            .description("后台API接口")
            // 作者
            .contact(new Contact("牧之", "http://localhost:6500/", "email@mail.com"))
            .license("The Apache License, Version 2.0")
            .licenseUrl("http://www.apache.org/licenses/LICENSE-2.0.html")
            .build();
    }

    /**
     * 新增 securityContexts 保持登录状态
     */
    private List<SecurityContext> securityContexts() {
        return new ArrayList(
            Collections.singleton(SecurityContext.builder()
                                                 .securityReferences(defaultAuth())
                                                 .forPaths(PathSelectors.regex("^(?!auth).*$"))
                                                 .build())
        );
    }

    private List<SecurityReference> defaultAuth() {
        AuthorizationScope authorizationScope = new AuthorizationScope("global", "accessEverything");
        AuthorizationScope[] authorizationScopes = new AuthorizationScope[1];
        authorizationScopes[0] = authorizationScope;
        return new ArrayList(
            Collections.singleton(new SecurityReference(ServingConstants.TOKEN_NAME, authorizationScopes)));
    }
}

#swagger
knife4j:
  #开启增强配置
  enable: true
  #开启生产环境屏蔽
  production: false