添加依赖

                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger2</artifactId>
                <version>2.9.2</version>
            </dependency>
            <dependency>
                <groupId>io.springfox</groupId>
                <artifactId>springfox-swagger-ui</artifactId>
                <version>2.9.2</version>
            </dependency>

添加配置

import com.github.xiaoymin.knife4j.spring.annotations.EnableKnife4j;
import com.google.common.base.Function;
import com.google.common.base.Predicate;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import springfox.documentation.RequestHandler;
import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

import java.util.Optional;

@Configuration
@EnableSwagger2
@EnableKnife4j
public class Swagger2 {
    // 定义分隔符
    private static final String splitor = ";";

    /**
     * 创建API应用
     * apiInfo() 增加API相关信息
     * 通过select()函数返回一个ApiSelectorBuilder实例,用来控制哪些接口暴露给Swagger来展现，
     * 本例采用指定扫描的包路径来定义指定要建立API的目录。
     *
     * @return
     */
    @Bean
    public Docket createRestApi() {
        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo())
                .select()
                .apis(basePackage("com.a.web" + splitor +
                        "com.a.controller")
                )
                .paths(PathSelectors.any())
                .build();
    }

    /**
     * 创建该API的基本信息（这些基本信息会展现在文档页面中）
     * 访问地址：http://项目实际地址/swagger-ui.html
     *
     * @return
     */
    private ApiInfo apiInfo() {
        return new ApiInfoBuilder()
                .title("Knife4j 接口文档")
                .description("Knife4j 接口文档")
                .termsOfServiceUrl("http://localhost:8088/doc.html")
                .contact("lcl")
                .version("1.0")
                .build();
    }


    /**
     * @param basePackage 所有包路径
     * @return Predicate<RequestHandler>
     * @author luoyu
     * @description 重写basePackage方法，使能够实现多包访问
     */
    public static Predicate<RequestHandler> basePackage(final String basePackage) {
        return input -> declaringClass(input).map(handlerPackage(basePackage)::apply).orElse(true);
    }

    /**
     * @param basePackage 所有包路径
     * @return Function<Class < ?>, Boolean>
     * @author luoyu
     * @description 重写basePackage方法，使能够实现多包访问
     */
    private static Function<Class<?>, Boolean> handlerPackage(final String basePackage) {
        return input -> {
            // 循环判断匹配
            for (String strPackage : basePackage.split(splitor)) {
                assert input != null;
                boolean isMatch = input.getPackage().getName().startsWith(strPackage);
                if (isMatch) {
                    return true;
                }
            }
            return false;
        };
    }

    /**
     * @param input
     * @return Optional<? extends Class < ?>>
     * @author luoyu
     * @description 重写basePackage方法，使能够实现多包访问
     */
    private static Optional<Class<?>> declaringClass(RequestHandler input) {
        return Optional.ofNullable(input.declaringClass());
    }

    @Bean
    public Docket createRestApiForCs() {
        return new Docket(DocumentationType.SWAGGER_2).apiInfo(apiInfo()).select()
                .apis(RequestHandlerSelectors.basePackage("com.a.web.user"))
                .paths(PathSelectors.any()).build().groupName("用户管理").pathMapping("/");
    }

}