java/w9/CrawlerApp.java

import java.util.*;
import java.util.Date;

/**
 * Article类 - 表示爬虫抓取的文章
 */
class Article {
    private String title;
    private String content;
    private String author;      // 新增字段：作者
    private Date publishDate;  // 新增字段：发布时间

    public Article(String title, String content) {
        this.title = title;
        this.content = content;
        this.author = null;    // 默认值为null
        this.publishDate = null; // 默认值为null
    }

    public Article(String title, String content, String author, Date publishDate) {
        this.title = title;
        this.content = content;
        this.author = author;
        this.publishDate = publishDate;
    }

    // Getter 和 Setter 方法
    public String getTitle() { return title; }
    public void setTitle(String title) { this.title = title; }

    public String getContent() { return content; }
    public void setContent(String content) { this.content = content; }

    public String getAuthor() { return author; }
    public void setAuthor(String author) { this.author = author; }

    public Date getPublishDate() { return publishDate; }
    public void setPublishDate(Date publishDate) { this.publishDate = publishDate; }

    @Override
    public String toString() {
        String dateStr = (publishDate != null) ? publishDate.toString() : "未知";
        String authorStr = (author != null && !author.trim().isEmpty()) ? author : "未知";
        return "标题: " + title + ", 作者: " + authorStr + ", 发布时间: " + dateStr;
    }
}

/**
 * HistoryCommand类 - 记录命令历史
 */
class HistoryCommand {
    private List<String> historyList = new ArrayList<>();

    // 添加命令到历史记录
    public void addCommand(String command) {
        historyList.add(command);
    }

    // 获取所有历史记录
    public List<String> getHistory() {
        return new ArrayList<>(historyList); // 返回副本，防止外部修改
    }

    // 获取最近N条历史记录
    public List<String> getRecentHistory(int n) {
        if (n <= 0) return new ArrayList<>();
        int startIndex = Math.max(0, historyList.size() - n);
        return new ArrayList<>(historyList.subList(startIndex, historyList.size()));
    }

    // 清空历史记录
    public void clearHistory() {
        historyList.clear();
    }

    // 获取历史记录数量
    public int getHistoryCount() {
        return historyList.size();
    }
}

/**
 * 主程序 - 演示类功能
 */
public class CrawlerApp {
    // 模拟文章列表
    private static List<Article> articleList = new ArrayList<>();
    private static HistoryCommand history = new HistoryCommand();
    private static Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        System.out.println("=== 爬虫系统控制台 ===");
        System.out.println("命令列表:");
        System.out.println("  crawl  - 开始抓取文章");
        System.out.println("  list   - 显示已抓取的文章");
        System.out.println("  add    - 手动添加文章");
        System.out.println("  history - 查看命令历史");
        System.out.println("  clear  - 清空命令历史");
        System.out.println("  exit   - 退出系统");
        System.out.println("========================\n");

        // 添加一些示例文章
        articleList.add(new Article("Java编程入门", "Java是一种面向对象的编程语言...", "张三", new Date()));
        articleList.add(new Article("Python数据分析", "使用Python进行数据清洗和分析...", "李四", new Date()));

        boolean running = true;
        while (running) {
            System.out.print("> ");
            String input = scanner.nextLine().trim();

            if (input.isEmpty()) continue;

            // 记录命令历史
            history.addCommand(input);

            // 解析命令
            String[] parts = input.split("\\s+");
            String command = parts[0].toLowerCase();

            switch (command) {
                case "crawl":
                    handleCrawlCommand(parts);
                    break;
                case "list":
                    handleListCommand();
                    break;
                case "add":
                    handleAddCommand();
                    break;
                case "history":
                    handleHistoryCommand(parts);
                    break;
                case "clear":
                    history.clearHistory();
                    System.out.println("命令历史已清空");
                    break;
                case "exit":
                    System.out.println("退出系统...");
                    running = false;
                    break;
                default:
                    System.out.println("未知命令: " + command);
                    System.out.println("输入 'exit' 退出系统");
            }
        }
        scanner.close();
    }

    // 处理爬取命令
    private static void handleCrawlCommand(String[] parts) {
        String keyword = (parts.length > 1) ? parts[1] : "新闻";
        System.out.println("正在抓取关于 '" + keyword + "' 的文章...");

        // 模拟抓取过程
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        // 模拟抓取结果
        Article newArticle = new Article(
                "关于" + keyword + "的最新报道",
                "这是关于" + keyword + "的详细内容...",
                "系统抓取",
                new Date()
        );

        articleList.add(newArticle);
        System.out.println("抓取完成！新增文章: " + newArticle.getTitle());
    }

    // 处理列出文章命令
    private static void handleListCommand() {
        if (articleList.isEmpty()) {
            System.out.println("当前没有文章");
            return;
        }

        System.out.println("\n=== 已抓取的文章列表 ===");
        for (int i = 0; i < articleList.size(); i++) {
            System.out.println((i + 1) + ". " + articleList.get(i));
        }
        System.out.println("总共 " + articleList.size() + " 篇文章\n");
    }

    // 处理添加文章命令
    private static void handleAddCommand() {
        System.out.println("\n--- 添加新文章 ---");

        System.out.print("请输入文章标题: ");
        String title = scanner.nextLine().trim();

        System.out.print("请输入文章内容: ");
        String content = scanner.nextLine().trim();

        System.out.print("请输入作者(可选，直接回车跳过): ");
        String author = scanner.nextLine().trim();
        if (author.isEmpty()) author = null;

        System.out.print("请输入发布日期(yyyy-MM-dd，可选，直接回车跳过): ");
        String dateStr = scanner.nextLine().trim();
        Date publishDate = null;
        if (!dateStr.isEmpty()) {
            try {
                // 简单日期解析，实际项目中应该使用SimpleDateFormat
                publishDate = new Date();
            } catch (Exception e) {
                System.out.println("日期格式错误，使用当前日期");
                publishDate = new Date();
            }
        }

        Article newArticle = new Article(title, content, author, publishDate);
        articleList.add(newArticle);
        System.out.println("文章添加成功！\n");
    }

    // 处理历史命令
    private static void handleHistoryCommand(String[] parts) {
        if (parts.length > 1 && parts[1].equals("count")) {
            System.out.println("历史命令总数: " + history.getHistoryCount());
            return;
        }

        List<String> historyList = history.getHistory();
        if (historyList.isEmpty()) {
            System.out.println("命令历史为空");
            return;
        }

        System.out.println("\n=== 命令历史 ===");
        for (int i = 0; i < historyList.size(); i++) {
            System.out.println((i + 1) + ". " + historyList.get(i));
        }
        System.out.println();
    }
}