spring-boot2.6.5整合swagger 3.0.0

1. 添加依赖

<parent>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-parent</artifactId>
	<version>2.6.5</version>
</parent>
<dependency>
	<groupId>io.springfox</groupId>
	<artifactId>springfox-boot-starter</artifactId>
	<version>3.0.0</version>
</dependency>

2.  添加配置文件

application.yml 或applicaiton.properties 中添 必须 加如下配置

spring:
  mvc:
    pathmatch:
      matching-strategy: ant_path_matcher

3.  启动类上添加@EnableSwagger2 注解

4. 访问地址

http://127.0.0.1:8080/swagger-ui/index.html

 springboot其他版本可参考：Springboot ✚ Swagger各版本整理_swagger版本-优快云博客

5. 遇到的问题

5.1 报错信息

org.springframework.context.ApplicationContextException: Failed to start bean ‘documentationPluginsBootstrapper’; nested exception is java.lang.NullPointerException

5.2 问题原因

Springfox 设置 Spring MVC 的路径匹配策略是 ant-path-matcher，而 Spring Boot 2.6.x版本的默认匹配策略是 path-pattern-matcher，这就造成了上面的报错

5.3 解决方法 

• 尝试使用 spring.mvc.pathmatch.matching-strategy: ant_path_matcher，未生效。这是网上大多数的解决办法

 实际解决方法：

@Configuration
public class WebConfiguration {
    @Bean
    public static BeanPostProcessor springfoxHandlerProviderBeanPostProcessor() {
        return new BeanPostProcessor() {

            @Override
            public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
                if (bean instanceof WebMvcRequestHandlerProvider || bean instanceof WebFluxRequestHandlerProvider) {
                    customizeSpringfoxHandlerMappings(getHandlerMappings(bean));
                }
                return bean;
            }

            private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(List<T> mappings) {
                List<T> copy = mappings.stream()
                        .filter(mapping -> mapping.getPatternParser() == null)
                        .collect(Collectors.toList());
                mappings.clear();
                mappings.addAll(copy);
            }

            @SuppressWarnings("unchecked")
            private List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {
                try {
                    Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");
                    field.setAccessible(true);
                    return (List<RequestMappingInfoHandlerMapping>) field.get(bean);
                } catch (IllegalArgumentException | IllegalAccessException e) {
                    throw new IllegalStateException(e);
                }
            }
        };
    }
}

参考文档： SpringBoot2.6.x 整合swagger3.0 报错Failed to start bean ‘documentationPluginsBootstrapper‘_spring.mvc.pathmatch.matching-strategy 不生效-优快云博客