ApplicationContextException: Failed to start bean ‘documentationPluginsBootstrapper‘；

spring boot2.6.2整合 swagger3.0.0导致项目启动失败

启动应用会报错 

org.springframework.context.ApplicationContextException: Failed to start bean 'documentationPluginsBootstrapper'; nested exception is java.lang.NullPointerException
    at org.springframework.context.support.DefaultLifecycleProcessor.doStart(DefaultLifecycleProcessor.java:181) ~[spring-context-5.3.10.jar:5.3.10]
    at org.springframework.context.support.DefaultLifecycleProcessor.access$200(DefaultLifecycleProcessor.java:54) ~[spring-context-5.3.10.jar:5.3.10]

使用 spring.mvc.pathmatch.matching-strategy: ant_path_matcher，未生效。

环境依赖

jdk8
spring boot 2.6.2
swagger [springfox-boot-starter(3.0.0)]

解决方案:

首先需要添加配置（必须）

spring:
  mvc:
    pathmatch:
      matching-strategy: ant_path_matcher

package io.renren.config;

import io.swagger.annotations.ApiOperation;
import org.springframework.boot.actuate.autoconfigure.endpoint.web.CorsEndpointProperties;
import org.springframework.boot.actuate.autoconfigure.endpoint.web.WebEndpointProperties;
import org.springframework.boot.actuate.autoconfigure.web.server.ManagementPortType;
import org.springframework.boot.actuate.endpoint.ExposableEndpoint;
import org.springframework.boot.actuate.endpoint.web.*;
import org.springframework.boot.actuate.endpoint.web.annotation.ControllerEndpointsSupplier;
import org.springframework.boot.actuate.endpoint.web.annotation.ServletEndpointsSupplier;
import org.springframework.boot.actuate.endpoint.web.servlet.WebMvcEndpointHandlerMapping;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.ApiKey;
import springfox.documentation.service.SecurityScheme;
import springfox.documentation.spi.documentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import static com.google.common.collect.Lists.newArrayList;

@Configuration
@EnableSwagger2
public class SwaggerConfig implements WebMvcConfigurer {

    @Bean
    public Docket createRestApi() {
        return new Docket(documentationType.SWAGGER_2)
            .apiInfo(apiInfo())
            .select()
            //加了ApiOperation注解的类，才生成接口文档
            .apis(RequestHandlerSelectors.withMethodAnnotation(ApiOperation.class))
            //包下的类，才生成接口文档
            //.apis(RequestHandlerSelectors.basePackage("io.renren.controller"))
            .paths(PathSelectors.any())
            .build()
            .securitySchemes(security());
    }

    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
            .title("唐芮棋")
            .description("rich-tang文档")
            .termsOfServiceUrl("rich.hk.com")
            .version("3.0.0")
            .build();
    }

    private List security() {
        return newArrayList(
            new ApiKey("token", "token", "header")
        );
    }

    @Bean
    public WebMvcEndpointHandlerMapping webEndpointServletHandlerMapping(
            WebEndpointsSupplier webEndpointsSupplier, ServletEndpointsSupplier servletEndpointsSupplier,
            ControllerEndpointsSupplier controllerEndpointsSupplier, EndpointMediaTypes endpointMediaTypes,
            CorsEndpointProperties corsProperties, WebEndpointProperties webEndpointProperties, Environment environment) {
        List> allEndpoints = new ArrayList<>();
        Collection webEndpoints = webEndpointsSupplier.getEndpoints();
        allEndpoints.addAll(webEndpoints);
        allEndpoints.addAll(servletEndpointsSupplier.getEndpoints());
        allEndpoints.addAll(controllerEndpointsSupplier.getEndpoints());
        String basePath = webEndpointProperties.getbasePath();
        EndpointMapping endpointMapping = new EndpointMapping(basePath);
        boolean shouldRegisterlinksMapping = webEndpointProperties.getDiscovery().isEnabled() &&
                (org.springframework.util.StringUtils.hasText(basePath) || ManagementPortType.get(environment).equals(ManagementPortType.DIFFERENT));
        return new WebMvcEndpointHandlerMapping(endpointMapping, webEndpoints, endpointMediaTypes, corsProperties.toCorsConfiguration(), new EndpointlinksResolver(allEndpoints, basePath), shouldRegisterlinksMapping, null);
    }

}