1.添加依赖

<dependency>
    <groupId>com.github.xiaoymin</groupId>
    <artifactId>knife4j-spring-boot-starter</artifactId>
</dependency>

2.配置类

package com.cj.system.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
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.Contact;
import springfox.documentation.service.Parameter;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2WebMvc;

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

@Configuration
@EnableSwagger2WebMvc
public class Knife4jConfig {
    @Bean
    public Docket adminApiConfig(){
        List<Parameter> pars = new ArrayList<>();
        ParameterBuilder tokenPar = new ParameterBuilder();
        tokenPar.name("token")
                .description("用户token")
                .defaultValue("")
                .modelRef(new ModelRef("string"))
                .parameterType("header")
                .required(false)
                .build();
        pars.add(tokenPar.build());
        //添加head参数end

        Docket adminApi = new Docket(DocumentationType.SWAGGER_2)
                .groupName("adminApi")
                .apiInfo(adminApiInfo())
                .select()
                //只显示admin路径下的页面
                .apis(RequestHandlerSelectors.basePackage("com.cj"))
                .paths(PathSelectors.regex("/admin/.*"))
                .build()
                .globalOperationParameters(pars);
        return adminApi;
    }

    private ApiInfo adminApiInfo(){

        return new ApiInfoBuilder()
                .title("后台管理系统-API文档")
                .description("本文档描述了后台管理系统微服务接口定义")
                .version("1.0")
                .contact(new Contact("cj", "http://cj.com", "cj@qq.com"))
                .build();
    }
}

3.加注解

package com.cj.system.controller;

import com.atguigu.model.system.SysRole;
import com.cj.system.mapper.SysRoleMapper;
import com.cj.system.service.SysRoleService;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@Api(tags = "角色管理")
@RestController
@RequestMapping("admin/system/sysRole")
public class SysRoleController {
    @Autowired
    private SysRoleService sysRoleService;

    @ApiOperation(value = "获取全部角色列表")
    @GetMapping("findAll")
    public List<SysRole> findAll(){
        List<SysRole> list = sysRoleService.list();
        return list;

    }
    @DeleteMapping("remove/{id}")
    public boolean remove(@PathVariable("id") Long id){
        boolean b = sysRoleService.removeById(id);
        return b;
    }
}

4.访问

localhost:8800/doc.html