<dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-boot-starter</artifactId>
            <version>3.0.0</version>
        </dependency>

package org.fh.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.oas.annotations.EnableOpenApi;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;

/**
 * 说明：Swagger 接口API生成
 * 作者：FH Admin
 * from fhadmin.org
 */
@Configuration
@EnableOpenApi
public class SwaggerConfig {

    @Bean
    public Docket createRestApi() {
        return new Docket(DocumentationType.OAS_30)
                .apiInfo(apiInfo())
                .select()
                .apis(RequestHandlerSelectors.basePackage("org.fh.controller"))    // 为当前包路径
                .paths(PathSelectors.any())
                .build();
    }

    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title("FH Admin Swagger3 RESTful API")     // 页面标题
                .version("3.0")                                // 版本号
                .description("fhadmin.org")                    // 描述
                .build();
    }

}

package org.fh.config;

import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

/**
 * 说明：Swagger 拦截配置
 * 作者：FH Admin
 * from fhadmin.org
 */
@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

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

    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        registry.addViewController("/swagger-ui/")
                .setViewName("forward:/swagger-ui/index.html");
    }
}

处理类上加注解，比如
@Api("用户注册登录接口")

在方法上加注解，比如
@ApiOperation(value = "登录", notes="校验登录是否成功")
@ApiImplicitParam(name = "KEYDATA", value = "用户名密码混淆码组合", paramType = "query", required = true, dataType = "String")