1. pom.xml导入Swagger依赖

<!--swagger3-->
<dependency>
   <groupId>org.springdoc</groupId>
   <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
   <version>2.0.2</version>
</dependency>

2.创建SwaggerConfig配置类，添加@Configuration注解

import io.swagger.v3.oas.models.OpenAPI;
import io.swagger.v3.oas.models.info.Info;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class SwaggerConfig {

    @Bean
    public OpenAPI springShopOpenAPI() {
        return new OpenAPI()
                .info(new Info().title("接口文档")
                        .description("学生成绩管理系统API文档")
                        .version("v1"));
    }

}

3.在controller类中（可不添加以下注解）添加@Tag、@Operation注解，注: 当你只写了一个接口时，如果只是在类上@RestController上设置接口访问路径，会出现No operations defined in spec!，这是需要在方法上再加个GetMapping/PostMapping/PutMapping/DeleteMapping就可以解决了

import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.tags.Tag;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@Tag(name = "登录管理")
@RestController
@RequestMapping("/login")
public class LoginController {
    @Autowired
    UserService userService;

    /**
     * 登录
     * @param user
     * @return
     */
    @Operation(summary = "查询")
    @GetMapping("/ling")
    public AjaxResult login(@RequestBody User user){
        User login = userService.login(user);
        return AjaxResult.success(login);
    }
}

4.访问：http://localhost:端口号/swagger-ui/index.htm