9：网络编程基础

package com.example;

import java.io.IOException;
import java.net.http.HttpClient;
import java.time.Duration;
import java.time.LocalDateTime;

public class SimpleDownloader {
    public static final String TEST_URL = "https://test.glimmer.org.cn/re/the_last_supper.png";
    private static final String SAVE_PATH = "small.bin";
    public static void main(String[] args) {
        // 创建一个HttpClient
        try (HttpClient client = HttpClient.newBuilder()
                .connectTimeout(Duration.ofSeconds(10))
                .followRedirects(HttpClient.Redirect.ALWAYS).build()) {
            // 下载计时
            LocalDateTime startTime = LocalDateTime.now();

            // TODO 构建request并发送这个request，需要添加header：“Authorization: Bearer glimmer_recruit”，否则返回401错误。你的代码应写在TODO和END TODO之间。





            // END TODO
            // 结束计时
            System.out.println("耗时：" + ((double) Duration.between(startTime, LocalDateTime.now()).toMillis() / 1000) + "s");
        } catch (IOException e) {
            System.err.println("出现错误！请检查你的网络连通性，或者咨询出题人服务器是否正常。");
            e.printStackTrace();
        } catch (InterruptedException e) {
            System.err.println("下载操作被中断！");
            e.printStackTrace();
        }
    }
}

<dependency>
    <groupId>com.squareup.okhttp3</groupId>
    <artifactId>okhttp</artifactId>
    <version>4.12.0</version>
</dependency>

https://www.bilibili.com/video/BV12yN264EwR/?share_source=copy_web&vd_source=3848787f4de6668e568f67f4434057ac

String share_source = "copy_web";
String vd_source = "3848787f4de6668e568f67f4434057ac";
String url = "https://www.bilibili.com/video/BV12yN264EwR/" + "?" +
        "share_source" + "=" + share_source + "&" +
        "vd_source" + "=" + vd_source;

package com.example;

import com.alibaba.fastjson2.JSON;
import okhttp3.*;

import java.io.IOException;

public class UserManager {
    private static final String host = "https://test.glimmer.org.cn";
    private static final String auth = "Bearer glimmer_recruit";
    private static final OkHttpClient client = new OkHttpClient();
    public record User(long id, String nickname) {}

    // 新增用户
    public static boolean addUser(User user) {
        Request request = new Request.Builder()
                .url(host + "/users")
                .header("Authorization", auth)
                .post(RequestBody.create(JSON.toJSONString(user), MediaType.get("application/json")))
                .build();
        return execute(request);
    }

    // 删除目标id对应的用户
    public static boolean removeUser(long id) {
        Request request = new Request.Builder()
                .url(host + "/users/" + id)
                .header("Authorization", auth)
                .delete()
                .build();
        return execute(request);
    }

    // 更新目标用户的信息
    public static boolean updateUser(User user) {
        Request request = new Request.Builder()
                .url(host + "/users/" + user.id)
                .header("Authorization", auth)
                .put(RequestBody.create(JSON.toJSONString(user), MediaType.get("application/json")))
                .build();
        return execute(request);
    }

    // 根据id查询对应的用户
    public static User getUser(long id) {
        Request request = new Request.Builder()
                .url(host + "/users/" + id)
                .header("Authorization", auth)
                .get()
                .build();
        try (Response res = client.newCall(request).execute()) {
            if (res.isSuccessful()) {
                ResponseBody body = res.body();
                if (body != null) return JSON.parseObject(body.string(), User.class);
            }
        } catch (IOException e) {
            System.err.println("请求出现异常，请检查网络可达性");
        }
        return null;
    }

    // 简单提取重复代码，用于发送请求，并返回是否成功
    private static boolean execute(Request request) {
        try (Response res = client.newCall(request).execute()) {
            return res.isSuccessful();
        } catch (IOException e) {
            System.err.println("请求出现异常，请检查网络可达性");
        }
        return false;
    }
}

package com.example;

import com.alibaba.fastjson2.JSON;
import com.alibaba.fastjson2.JSONArray;
import com.alibaba.fastjson2.JSONObject;
import okhttp3.*;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.*;
import java.util.concurrent.TimeUnit;

public class SimpleFileAgent {
    // TODO 请修改BASE_URL、API_KEY和MODEL
    private static final String API_KEY = "your_api_key";
    private static final String BASE_URL = "https://api.deepseek.com/chat/completions";
    private static final String MODEL = "deepseek-v4-flash";

    private static final OkHttpClient client = new OkHttpClient.Builder()
            .connectTimeout(30, TimeUnit.SECONDS)
            .readTimeout(60, TimeUnit.SECONDS)
            .build();

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print(">>> 请输入指令 (例如：读取 test.txt，总结重点并写入 summary.txt): ");
        String userInput = scanner.nextLine();
        String finalAnswer = runAgent(userInput);
        System.out.println("\n--- [Agent 最终输出] ---");
        System.out.println(finalAnswer);
    }

    // Agent控制流
    public static String runAgent(String userPrompt) {
        // 传递上下文，这里系统提示词写的比较简单
        List<Map<String, Object>> messages = new ArrayList<>();
        messages.add(Map.of("role", "system", "content", "你是一个能读写本地文件的助手，根据用户需求精准调用工具完成任务。"));
        messages.add(Map.of("role", "user", "content", userPrompt));

        while (true) {
            // 与LLM进行交互，获得回复
            JSONObject aiResponse = callChatApi(messages);
            JSONObject messageObj = aiResponse.getJSONArray("choices")
                    .getJSONObject(0)
                    .getJSONObject("message");
            // 将模型当前回答添加到上下文
            messages.add(messageObj);
            // 判断是否发起了工具调用，如果发起了则尝试调用外部函数
            JSONArray toolCalls = messageObj.getJSONArray("tool_calls");
            if (toolCalls != null && !toolCalls.isEmpty()) {
                for (int i = 0; i < toolCalls.size(); i++) {
                    JSONObject toolCall = toolCalls.getJSONObject(i);
                    // 获取当前调用的工具信息
                    String callId = toolCall.getString("id");
                    JSONObject function = toolCall.getJSONObject("function");
                    String funcName = function.getString("name");
                    JSONObject args = JSON.parseObject(function.getString("arguments"));
                    System.out.println("-> [Agent 正在执行工具] " + funcName + "(" + args + ")");
                    // 执行工具调用
                    String toolResult = executeFileTool(funcName, args);
                    // 将外部函数的运行结果塞入上下文，交给下次while循环
                    messages.add(Map.of(
                            "role", "tool",
                            "tool_call_id", callId,
                            "name", funcName,
                            "content", toolResult
                    ));
                }
            } else {
                // 若不调用工具，说明全部执行完成，直接获取最终生成的文本
                return messageObj.getString("content");
            }
        }
    }

    // 利用Okhttp和Fastjson，与AI服务商提供的API进行交互
    private static JSONObject callChatApi(List<Map<String, Object>> messages) {
        // 组装请求体
        Map<String, Object> requestMap = new HashMap<>();
        requestMap.put("model", MODEL);
        requestMap.put("messages", messages);
        requestMap.put("tools", getToolsSchema());

        // 这是你需要发送的请求体
        String jsonBody = JSON.toJSONString(requestMap);

        JSONObject result = null;
        // TODO 请尝试向BASE_URL发起POST请求，并添加header，header中要填上你的API_KEY，然后将响应体中的字符串转换为JSONObject对象，再通过return返回。





        // END TODO
        return result;
    }

    // 返回一个List，内容包含LLM可调用的外部函数
    private static List<Map<String, Object>> getToolsSchema() {
        return List.of(
                Map.of(
                        "type", "function",
                        "function", Map.of(
                                "name", "read_file",
                                "description", "读取指定本地路径的文件内容",
                                "parameters", Map.of(
                                        "type", "object",
                                        "properties", Map.of(
                                                "file_path", Map.of(
                                                        "type", "string",
                                                        "description", "目标文件系统路径")),
                                        "required", List.of("file_path")))),
                Map.of(
                        "type", "function",
                        "function", Map.of(
                                "name", "write_file",
                                "description", "将生成的内容保存或覆盖写入到指定的本地文件",
                                "parameters", Map.of(
                                        "type", "object",
                                        "properties", Map.of(
                                                "file_path", Map.of(
                                                        "type", "string",
                                                        "description", "保存的目标文件名"),
                                                "content", Map.of(
                                                        "type", "string",
                                                        "description", "要写入文件的具体内容")),
                                        "required", List.of("file_path", "content")))));
    }

    // 为LLM提供简单的文件读写函数
    private static String executeFileTool(String name, JSONObject args) {
        try {
            if ("read_file".equals(name)) {
                String filePath = args.getString("file_path");
                return Files.readString(Path.of(filePath));
            } else if ("write_file".equals(name)) {
                String filePath = args.getString("file_path");
                String content = args.getString("content");
                Files.writeString(Path.of(filePath), content);
                return "文件写入成功: " + filePath;
            }
        } catch (IOException e) {
            return "工具执行错误(读取/保存异常): " + e.getMessage();
        }
        return "未知工具名";
    }
}