✨ 完成大作业部分，并完成第一次黑箱测试

src/main/java/top/lichx/webclassbackend/WebClassBackendApplication.java

@@ -2,8 +2,10 @@ package top.lichx.webclassbackend;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableAsync;
 
 @SpringBootApplication
+@EnableAsync
 public class WebClassBackendApplication {
 
     public static void main(String[] args) {

src/main/java/top/lichx/webclassbackend/controller/ArticleController.java

@@ -0,0 +1,117 @@
+package top.lichx.webclassbackend.controller;
+
+import com.baomidou.mybatisplus.core.metadata.IPage;
+import jakarta.annotation.Resource;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.core.task.TaskExecutor;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.web.bind.annotation.*;
+import top.lichx.webclassbackend.pojo.dto.ArticleInfoDTO;
+import top.lichx.webclassbackend.pojo.vo.ArticleManagerInfoVO;
+import top.lichx.webclassbackend.pojo.vo.VisibleUserInfoVO;
+import top.lichx.webclassbackend.result.Result;
+import top.lichx.webclassbackend.service.ArticleManagerService;
+import top.lichx.webclassbackend.service.UserService;
+import top.lichx.webclassbackend.util.AIUtil;
+import top.lichx.webclassbackend.util.COSIO;
+
+import java.time.format.DateTimeFormatter;
+
+@Slf4j
+@RestController
+@RequestMapping("/article")
+public class ArticleController {
+
+    @Resource
+    private ArticleManagerService articleManagerService;
+
+    @Resource
+    private UserService userService;
+
+    @Resource
+    private COSIO cosio;
+
+    @Resource
+    private AIUtil aiUtil;
+
+    @Resource
+    private TaskExecutor taskExecutor;
+
+    @GetMapping("/page")
+    public Result<IPage<ArticleManagerInfoVO>> getUserManagerInfoPage(@RequestParam int page, @RequestParam int size) {
+        return Result.success("", articleManagerService.getArticleManagerInfoPage(page, size));
+    }
+
+    @GetMapping("/total")
+    public Result<Integer> total() {
+        return Result.success("", articleManagerService.getTotal());
+    }
+
+    @GetMapping("/userAvatar")
+    public Result<?> getUserAvatar(@RequestParam String userId) {
+        var user = userService.getUserByUserId(Integer.parseInt(userId));
+        if (user == null)
+            return Result.error("用户不存在");
+        return Result.success("", cosio.GetFileLink(user.getAvatarPath()));
+    }
+
+    @GetMapping("/userInfo")
+    public Result<?> getUserInfo(@RequestParam String userId) {
+        var user = userService.getUserByUserId(Integer.parseInt(userId));
+        if (user == null)
+            return Result.error("用户不存在");
+        var returnVO = new VisibleUserInfoVO();
+        returnVO.setUserId("" + user.getId());
+        returnVO.setUserName(user.getName());
+        returnVO.setUserEmail(user.getEmail());
+        returnVO.setUserAvatarPath(user.getAvatarPath());
+        returnVO.setUserAmount(user.getAmount());
+        returnVO.setUserBirthday(user.getBirth().format(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
+        return Result.success("", returnVO);
+    }
+
+    @PostMapping("/addArticle")
+    public Result<?> addArticle(@RequestBody ArticleInfoDTO articleInfoDTO) {
+        var id = articleManagerService.InsertArticleInfo(articleInfoDTO);
+        UpdateArticleMainIdea(id, articleInfoDTO.getTitle(), articleInfoDTO.getContent());
+        return Result.success("添加文章成功");
+    }
+
+    @PostMapping("/updateArticle")
+    public Result<?> updateArticle(@RequestBody ArticleInfoDTO articleInfoDTO) {
+        articleManagerService.UpdateArticleInfo(articleInfoDTO);
+        UpdateArticleMainIdea(articleInfoDTO.getId(), articleInfoDTO.getTitle(), articleInfoDTO.getContent());
+        return Result.success("更新文章成功");
+    }
+
+    @Async
+    protected void UpdateArticleMainIdea(Integer articleId, String title, String content) {
+        System.out.println("task start");
+        taskExecutor.execute(() -> {
+            var mainIdea = aiUtil.GetMainIdeaOfArticle(title, content);
+            System.out.println(articleId);
+            System.out.println(mainIdea);
+            articleManagerService.UpdateArticleMainIdea(articleId, mainIdea);
+        });
+    }
+
+    @GetMapping("/page/{authorName}")
+    public Result<?> GetArticleById(@PathVariable String authorName, @RequestParam int page, @RequestParam int size) {
+        var article = articleManagerService.GetArticlesByAuthorName(authorName, page, size);
+        if (article == null)
+            return Result.error("文章不存在");
+        return Result.success("", article);
+    }
+
+    @GetMapping("/total/{authorName}")
+    public Result<?> GetUserArticleTotal(@PathVariable String authorName) {
+        var result = articleManagerService.GetArticleCountByAuthorName(authorName);
+        return Result.success("", result);
+    }
+
+    @GetMapping("/deleteArticle")
+    public Result<?> deleteArticle(@RequestParam String id) {
+        articleManagerService.deleteArticleById(Integer.parseInt(id));
+        return Result.success("删除文章成功");
+    }
+}

src/main/java/top/lichx/webclassbackend/controller/FileController.java

@@ -1,10 +1,9 @@
 package top.lichx.webclassbackend.controller;
 
 import jakarta.annotation.Resource;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.multipart.MultipartFile;
-import top.lichx.webclassbackend.pojo.vo.AvatarInfo;
+import top.lichx.webclassbackend.pojo.vo.AvatarInfoVO;
 import top.lichx.webclassbackend.result.Result;
 import top.lichx.webclassbackend.util.COSIO;
 
@@ -55,7 +54,7 @@ public class FileController {
         var fileName = cosio.UploadFile(file);
         file.delete();
         var fileURL = cosio.GetFileLink(fileName);
-        var avatarInfo = new AvatarInfo(fileName, fileURL);
+        var avatarInfo = new AvatarInfoVO(fileName, fileURL);
         return Result.success("文件上传成功", avatarInfo);
     }
 

src/main/java/top/lichx/webclassbackend/controller/Login.java

@@ -17,6 +17,7 @@ import top.lichx.webclassbackend.util.PasswordUtil;
 
 import java.time.LocalDate;
 import java.time.format.DateTimeFormatter;
+import java.util.Random;
 
 @RestController
 @RequestMapping("/login")
@@ -195,7 +196,7 @@ public class Login {
         if (user != null && passwordUtil.matches(password,user.getPassword())) {
             String token = JwtUtil.generateToken(user.getName());
             // 设置HttpOnly和Secure属性的Cookie
-            response.setHeader("Set-Cookie", "Authorization=Bearer " + token + "; HttpOnly; Max-Age=86400; Path=/; SameSite=Strict");
+            response.setHeader("Set-Cookie", "Authorization=Bearer " + token + "; HttpOnly; Secure; Max-Age=86400; Path=/; SameSite=Strict");
 //            response.setHeader("Set-Cookie", "token=Bearer " + token + "; HttpOnly; Secure; Path=/; SameSite=Strict");
             return Result.success("登录成功");
         }
@@ -236,7 +237,11 @@ public class Login {
         user.setPassword(passwordUtil.encrypt(registerDTO.getPassword()));
         user.setEmail(registerDTO.getEmail());
         user.setBirth(LocalDate.parse(registerDTO.getBirth(), DateTimeFormatter.ISO_LOCAL_DATE).atStartOfDay());
-        user.setAvatarURL(registerDTO.getAvatarFile());
+        user.setAvatarPath(registerDTO.getAvatarFile());
+        Random random = new Random();
+        int randomNumber = 100 + random.nextInt(901);
+        String randomString = Integer.toString(randomNumber);
+        user.setAmount(randomString);
 
         if (!identifyingCode.testIdentifyingCode(registerDTO.getEmail(),
                 IdentifyingCode.IdentifyingCodeType.REGISTER,

src/main/java/top/lichx/webclassbackend/controller/User.java

@@ -46,7 +46,8 @@ public class User {
         returnVO.setUserId("" + user.getId());
         returnVO.setUserName(user.getName());
         returnVO.setUserEmail(user.getEmail());
-        returnVO.setUserAvatar(cosio.GetFileLink(user.getAvatarURL()));
+        returnVO.setUserAvatarPath(user.getAvatarPath());
+        returnVO.setUserAmount(user.getAmount());
         returnVO.setUserBirthday(user.getBirth().format(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
         return Result.success("", returnVO);
     }
@@ -69,6 +70,6 @@ public class User {
         var user = userService.getUserByUserName(username);
         if (user == null)
             return Result.error("用户不存在");
-        return Result.success("", cosio.GetFileLink(user.getAvatarURL()));
+        return Result.success("", cosio.GetFileLink(user.getAvatarPath()));
     }
 }

src/main/java/top/lichx/webclassbackend/controller/UserManager.java

@@ -52,14 +52,14 @@ public class UserManager {
         return Result.success("更新用户成功");
     }
 
-    @GetMapping("deleteUser")
+    @GetMapping("/deleteUser")
     public Result<?> deleteUser(@RequestParam Integer id)
     {
         userManagerService.deleteUserManagerInfo(id);
         return Result.success("删除用户成功");
     }
 
-    @GetMapping("total")
+    @GetMapping("/total")
     public Result<Integer> total(@RequestParam String situation)
     {
         return Result.success("", userManagerService.getTotal(situation));

src/main/java/top/lichx/webclassbackend/mapper/articleManagerInfoMapper.java

@@ -0,0 +1,9 @@
+package top.lichx.webclassbackend.mapper;
+
+import com.baomidou.mybatisplus.core.mapper.BaseMapper;
+import org.apache.ibatis.annotations.Mapper;
+import top.lichx.webclassbackend.pojo.entity.Article;
+
+@Mapper
+public interface articleManagerInfoMapper extends BaseMapper<Article> {
+}

src/main/java/top/lichx/webclassbackend/pojo/dto/ArticleInfoDTO.java

@@ -0,0 +1,11 @@
+package top.lichx.webclassbackend.pojo.dto;
+
+import lombok.Data;
+
+@Data
+public class ArticleInfoDTO {
+    private Integer id;
+    private String author;
+    private String title;
+    private String content;
+}

src/main/java/top/lichx/webclassbackend/pojo/dto/In.java

@@ -1,9 +0,0 @@
-package top.lichx.webclassbackend.pojo.dto;
-
-import lombok.Data;
-
-@Data
-public class In {
-    Long id;
-    String test;
-}

src/main/java/top/lichx/webclassbackend/pojo/dto/LoginDTO.java

@@ -4,7 +4,6 @@ import lombok.Data;
 
 @Data
 public class LoginDTO {
-
     private String usernameOrEmail;
     private String password;
 }

src/main/java/top/lichx/webclassbackend/pojo/entity/Article.java

@@ -0,0 +1,29 @@
+package top.lichx.webclassbackend.pojo.entity;
+
+import com.baomidou.mybatisplus.annotation.TableField;
+import com.baomidou.mybatisplus.annotation.TableName;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+@TableName("article")
+public class Article {
+
+    Integer id;
+    String title;
+    String author;
+    @TableField("mainIdea")
+    String mainIdea;
+    String content;
+
+    public Article(Integer id, String title, String author, String content) {
+        this.id = id;
+        this.title = title;
+        this.author = author;
+        this.content = content;
+        this.mainIdea = "概述生成中...";
+    }
+}

src/main/java/top/lichx/webclassbackend/pojo/entity/User.java

@@ -18,6 +18,7 @@ public class User {
     String password;
     String email;
     LocalDateTime birth;
-    @TableField("avatarURL")
+    @TableField("avatarPath")
-    String avatarURL;
+    String avatarPath;
+    String amount;
 }

src/main/java/top/lichx/webclassbackend/pojo/vo/ArticleManagerInfoVO.java

@@ -0,0 +1,14 @@
+package top.lichx.webclassbackend.pojo.vo;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+public class ArticleManagerInfoVO {
+    Integer id;
+    String name;
+    Integer amount;
+}

src/main/java/top/lichx/webclassbackend/pojo/vo/AvatarInfoVO.java

@@ -8,7 +8,7 @@ import java.net.URL;
 @Data
 @AllArgsConstructor
 @NoArgsConstructor
-public class AvatarInfo {
+public class AvatarInfoVO {
     private String avatarFilePath;
     private URL avatarFileURL;
 }

src/main/java/top/lichx/webclassbackend/pojo/vo/VisibleUserInfoVO.java

@@ -13,6 +13,7 @@ public class VisibleUserInfoVO {
     private String userId;
     private String userName;
     private String userEmail;
-    private URL userAvatar;
+    private String userAvatarPath;
     private String userBirthday;
+    private String userAmount;
 }

src/main/java/top/lichx/webclassbackend/service/ArticleManagerService.java

@@ -0,0 +1,24 @@
+package top.lichx.webclassbackend.service;
+
+import com.baomidou.mybatisplus.core.metadata.IPage;
+import top.lichx.webclassbackend.pojo.dto.ArticleInfoDTO;
+import top.lichx.webclassbackend.pojo.entity.Article;
+import top.lichx.webclassbackend.pojo.vo.ArticleManagerInfoVO;
+
+public interface ArticleManagerService {
+
+    IPage<ArticleManagerInfoVO> getArticleManagerInfoPage(int page, int size);
+    Integer getArticleManagerInfoLastId();
+    Integer getTotal();
+    Integer InsertArticleInfo(ArticleInfoDTO articleInfoDTO);
+
+    void UpdateArticleInfo(ArticleInfoDTO articleInfoDTO);
+
+    void UpdateArticleMainIdea(Integer id, String mainIdea);
+
+    IPage<Article> GetArticlesByAuthorName(String authorName, Integer page, Integer size);
+
+    Integer GetArticleCountByAuthorName(String authorName);
+
+    void deleteArticleById(Integer id);
+}

src/main/java/top/lichx/webclassbackend/service/Test.java

@@ -1,5 +0,0 @@
-package top.lichx.webclassbackend.service;
-
-public interface Test {
-    void test();
-}

src/main/java/top/lichx/webclassbackend/service/UserManagerService.java

@@ -10,5 +10,4 @@ public interface UserManagerService {
     public IPage<UserManagerInfo> getUserManagerInfoPage(int page, int size, String situation);
     public Integer getUserManagerInfoLastId();
     public Integer getTotal(String situation);
-
 }

src/main/java/top/lichx/webclassbackend/service/UserService.java

@@ -5,6 +5,7 @@ import top.lichx.webclassbackend.pojo.entity.User;
 public interface UserService {
     public void insertUser(User user);
     public User getUserByUserName(String userName);
+    public User getUserByUserId(Integer userId);
     public void changeUserPasswordByUserName(String userName, String password);
 
     public User getUserByEmail(String email);

src/main/java/top/lichx/webclassbackend/service/impl/ArticleManagerServiceImpl.java

@@ -0,0 +1,120 @@
+package top.lichx.webclassbackend.service.impl;
+
+import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
+import com.baomidou.mybatisplus.core.metadata.IPage;
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
+import jakarta.annotation.Resource;
+import org.springframework.stereotype.Service;
+import top.lichx.webclassbackend.mapper.articleManagerInfoMapper;
+import top.lichx.webclassbackend.mapper.userMapper;
+import top.lichx.webclassbackend.pojo.dto.ArticleInfoDTO;
+import top.lichx.webclassbackend.pojo.entity.Article;
+import top.lichx.webclassbackend.pojo.entity.User;
+import top.lichx.webclassbackend.pojo.vo.ArticleManagerInfoVO;
+import top.lichx.webclassbackend.service.ArticleManagerService;
+
+import java.util.ArrayList;
+import java.util.List;
+
+@Service
+public class ArticleManagerServiceImpl implements ArticleManagerService {
+    @Resource
+    private userMapper userMapper;
+    @Resource
+    private articleManagerInfoMapper articleManagerInfoMapper;
+
+    @Override
+    public IPage<ArticleManagerInfoVO> getArticleManagerInfoPage(int page, int size) {
+        // 查询所有用户的 id 和 name
+        List<User> users = userMapper.selectList(null);
+
+        // 创建结果列表
+        List<ArticleManagerInfoVO> result = new ArrayList<>();
+
+        // 遍历用户列表
+        for (User user : users) {
+            String name = user.getName();
+
+            // 查询 articleManagerInfoMapper 中 author 为 name 的数量
+            int articleCount = articleManagerInfoMapper.selectCount(
+                    new QueryWrapper<Article>().eq("author", name)
+            ).intValue();
+
+            // 将结果添加到列表中
+            result.add(new ArticleManagerInfoVO(user.getId(), name, articleCount));
+        }
+
+        Page<ArticleManagerInfoVO> pageResult = new Page<>(page, size);
+        pageResult.setRecords(result);
+        pageResult.setTotal(users.size());
+        return pageResult;
+    }
+
+    @Override
+    public Integer getArticleManagerInfoLastId() {
+        Article lastRecord = articleManagerInfoMapper.selectOne(
+                new QueryWrapper<Article>().orderByDesc("id").last("LIMIT 1")
+        );
+        // 如果记录为空，返回 0，否则返回最后一条记录的 ID + 1
+        return lastRecord == null ? 0 : lastRecord.getId() + 1;
+    }
+
+    @Override
+    public Integer getTotal() {
+        return userMapper.selectCount(null).intValue();
+    }
+
+    @Override
+    public Integer InsertArticleInfo(ArticleInfoDTO articleInfoDTO)
+    {
+        Article article = new Article(getArticleManagerInfoLastId(), articleInfoDTO.getTitle(), articleInfoDTO.getAuthor(), articleInfoDTO.getContent());
+        articleManagerInfoMapper.insert(article);
+        return article.getId();
+    }
+
+    @Override
+    public void UpdateArticleInfo(ArticleInfoDTO articleInfoDTO)
+    {
+        Article article = articleManagerInfoMapper.selectById(articleInfoDTO.getId());
+        if(!article.getAuthor().equals(articleInfoDTO.getAuthor()))
+        {
+            throw new RuntimeException("作者不一致");
+        }
+        if (article != null) {
+            article.setTitle(articleInfoDTO.getTitle());
+            article.setContent(articleInfoDTO.getContent());
+            article.setMainIdea("概述生成中...");
+            articleManagerInfoMapper.updateById(article);
+        }
+    }
+
+    @Override
+    public void UpdateArticleMainIdea(Integer id, String mainIdea) {
+        Article article = articleManagerInfoMapper.selectById(id);
+        if (article != null) {
+            article.setMainIdea(mainIdea);
+            articleManagerInfoMapper.updateById(article);
+        }
+    }
+
+    @Override
+    public IPage<Article> GetArticlesByAuthorName(String authorName, Integer page, Integer size)
+    {
+        return articleManagerInfoMapper.selectPage(new Page<>(page, size),
+                new QueryWrapper<Article>().eq("author", authorName));
+    }
+
+    @Override
+    public Integer GetArticleCountByAuthorName(String authorName)
+    {
+        return articleManagerInfoMapper.selectCount(
+                new QueryWrapper<Article>().eq("author", authorName)
+        ).intValue();
+    }
+
+    @Override
+    public void deleteArticleById(Integer id)
+    {
+        articleManagerInfoMapper.deleteById(id);
+    }
+}

src/main/java/top/lichx/webclassbackend/service/impl/TestImpl.java

@@ -1,13 +0,0 @@
-package top.lichx.webclassbackend.service.impl;
-
-import org.springframework.stereotype.Service;
-import top.lichx.webclassbackend.service.Test;
-
-@Service
-public class TestImpl implements Test {
-
-    @Override
-    public void test() {
-
-    }
-}

src/main/java/top/lichx/webclassbackend/service/impl/UserServiceImpl.java

@@ -5,7 +5,6 @@ import jakarta.annotation.Resource;
 import org.springframework.stereotype.Service;
 import top.lichx.webclassbackend.mapper.userMapper;
 import top.lichx.webclassbackend.pojo.entity.User;
-import top.lichx.webclassbackend.pojo.entity.UserManagerInfo;
 import top.lichx.webclassbackend.service.UserService;
 
 @Service
@@ -13,16 +12,26 @@ public class UserServiceImpl implements UserService {
     @Resource
     private userMapper webclassMapper;
 
+    @Override
     public void insertUser(User user) {
         webclassMapper.insert(user);
     }
 
+    @Override
     public User getUserByUserName(String userName) {
         QueryWrapper<User> queryWrapper = new QueryWrapper<>();
         queryWrapper.eq("name", userName);
         return webclassMapper.selectOne(queryWrapper);
     }
 
+    @Override
+    public User getUserByUserId(Integer userId) {
+        QueryWrapper<User> queryWrapper = new QueryWrapper<>();
+        queryWrapper.eq("id", userId);
+        return webclassMapper.selectOne(queryWrapper);
+    }
+
+    @Override
     public void changeUserPasswordByUserName(String userName, String password) {
         User user = getUserByUserName(userName);
         if (user != null) {
@@ -45,7 +54,6 @@ public class UserServiceImpl implements UserService {
         );
         // 如果记录为空，返回 0，否则返回最后一条记录的 ID
         return lastRecord == null ? 0 : lastRecord.getId() + 1;
-
     }
 
     @Override

src/main/java/top/lichx/webclassbackend/util/AIUtil.java

@@ -0,0 +1,72 @@
+package top.lichx.webclassbackend.util;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonObject;
+import jakarta.annotation.PostConstruct;
+import lombok.AllArgsConstructor;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.web.client.RestTemplate;
+
+import org.springframework.http.HttpHeaders;
+
+import java.util.concurrent.CompletableFuture;
+
+@Component
+public class AIUtil {
+    @Value("${deepseek.apikey}")
+    private String apikey;
+    @Value("${deepseek.apiurl}")
+    private String apiurl;
+    @Value("${deepseek.model}")
+    private String model;
+
+    public String GetMainIdeaOfArticle(String title, String content) {
+        Message[] messages = new Message[] {
+                new Message("system", "你需要总结出一篇文章的主要内容，写成概述，字数限制在100字以内，请尽量简洁明了，请直接输出观点，不要以：‘文章主要观点：’或‘文章概述：’开头，直接输出即可"),
+                new Message("user", "文章标题：" + title + " 文章内容：" + content)
+        };
+        BodyData bodyData = new BodyData(messages, model, false);
+        String jsonBody = new Gson().toJson(bodyData);
+        String response = SendPostRequest(jsonBody);
+        Gson gson = new Gson();
+        JsonObject jsonObject = gson.fromJson(response, JsonObject.class);
+        String mainIdea = jsonObject
+                .getAsJsonArray("choices")
+                .get(0)
+                .getAsJsonObject()
+                .getAsJsonObject("message")
+                .get("content")
+                .getAsString();
+        return mainIdea;
+    }
+
+    private String SendPostRequest(String jsonBody) {
+        RestTemplate restTemplate = new RestTemplate();
+        HttpHeaders headers = new HttpHeaders();
+        headers.set("Authorization", "Bearer " + apikey);
+        headers.set("Content-Type", "application/json");
+        HttpEntity<String> entity = new HttpEntity<String>(jsonBody, headers);
+        ResponseEntity<String> responseEntity = restTemplate.exchange(apiurl, HttpMethod.POST, entity, String.class);
+        if (responseEntity.getStatusCode().is2xxSuccessful()) {
+            return responseEntity.getBody();
+        } else {
+            return "生成文章大意失败";
+        }
+    }
+    @AllArgsConstructor
+    class BodyData {
+        Message[] messages;
+        String model;
+        boolean stream;
+    }
+    @AllArgsConstructor
+    class Message {
+        String role;
+        String content;
+    }
+
+}