java/继承+多态爬虫/CrawlerMain.java

import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;
import org.jsoup.select.Elements;
import java.util.ArrayList;
import java.util.List;

// ==================== 抽象爬虫父类 ====================
abstract class BaseCrawler {
    protected String baseUrl;

    public BaseCrawler(String baseUrl) {
        this.baseUrl = baseUrl;
    }

    protected Document getPage(String url) throws Exception {
        return Jsoup.connect(url)
                .userAgent("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")
                .timeout(15000)
                .get();
    }

    public abstract List<?> startCrawl();
}

// ==================== 实体类 ====================
class Movie {
    private String title;
    private String rating;

    public Movie(String title, String rating) {
        this.title = title;
        this.rating = rating;
    }

    @Override
    public String toString() {
        return "电影：《" + title + "》 | 评分：" + rating;
    }
}

class Hero {
    private String name;

    public Hero(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "英雄：" + name;
    }
}

class Weather {
    private String province;
    private String city;
    private String temperature;
    private String condition;

    public Weather(String province, String city, String temperature, String condition) {
        this.province = province;
        this.city = city;
        this.temperature = temperature;
        this.condition = condition;
    }

    @Override
    public String toString() {
        return "省份：" + province + " | 城市：" + city + " | 天气：" + condition + " | 温度：" + temperature;
    }
}

// ==================== 豆瓣电影爬虫 ====================
class MovieCrawler extends BaseCrawler {
    public MovieCrawler() {
        super("https://movie.douban.com/top250");
    }

    @Override
    public List<Movie> startCrawl() {
        List<Movie> list = new ArrayList<>();
        try {
            for (int i = 0; i < 250; i += 25) {
                Document doc = getPage(baseUrl + "?start=" + i);
                Elements items = doc.select(".item");
                for (Element e : items) {
                    String title = e.select(".title").first().text().split("/")[0].trim();
                    String rating = e.select(".rating_num").text();
                    list.add(new Movie(title, rating));
                }
                Thread.sleep(1000);
            }
        } catch (Exception e) {
            System.out.println("电影爬取失败");
        }
        return list;
    }
}

// ==================== 王者荣耀爬虫（绝对能打印英雄） ====================
class HeroCrawler extends BaseCrawler {
    public HeroCrawler() {
        super("https://pvp.qq.com/web201605/herolist.shtml");
    }

    @Override
    public List<Hero> startCrawl() {
        List<Hero> list = new ArrayList<>();
        try {
            Document doc = getPage(baseUrl);
            Elements heros = doc.select("ul.herolist li a");

            for (Element h : heros) {
                String name = h.text().trim();
                if (!name.isEmpty()) {
                    list.add(new Hero(name));
                }
            }
        } catch (Exception e) {
            System.out.println("英雄爬取失败");
        }
        return list;
    }
}

// ==================== 天气爬虫 ====================
class WeatherCrawler extends BaseCrawler {
    private static final String[][] cities = {
            {"北京","北京","101010100"},{"上海","上海","101020100"},{"天津","天津","101030100"},{"重庆","重庆","101040100"},
            {"河北","石家庄","101090101"},{"山西","太原","101100101"},{"辽宁","沈阳","101070101"},{"吉林","长春","101060101"},
            {"黑龙江","哈尔滨","101050101"},{"江苏","南京","101190101"},{"浙江","杭州","101210101"},{"安徽","合肥","101220101"},
            {"福建","福州","101230101"},{"江西","南昌","101240101"},{"山东","济南","101120101"},{"河南","郑州","101180101"},
            {"湖北","武汉","101200101"},{"湖南","长沙","101250101"},{"广东","广州","101280101"},{"海南","海口","101310101"},
            {"四川","成都","101270101"},{"贵州","贵阳","101260101"},{"云南","昆明","101290101"},{"陕西","西安","101110101"},
            {"甘肃","兰州","101160101"},{"青海","西宁","101150101"},{"内蒙古","呼和浩特","101080101"},{"广西","南宁","101300101"},
            {"西藏","拉萨","101140101"},{"宁夏","银川","101170101"},{"新疆","乌鲁木齐","101130101"},
            {"香港","香港","101320101"},{"澳门","澳门","101330101"},{"台湾","台北","101340101"}
    };

    public WeatherCrawler() {
        super("https://www.weather.com.cn/weather/");
    }

    @Override
    public List<Weather> startCrawl() {
        List<Weather> list = new ArrayList<>();
        try {
            for (String[] city : cities) {
                String province = city[0];
                String cityName = city[1];
                String code = city[2];
                Document doc = getPage(baseUrl + code + ".shtml");
                Element today = doc.select("ul.t li").first();
                if (today != null) {
                    String temp = today.select(".tem").text();
                    String wea = today.select(".wea").text();
                    list.add(new Weather(province, cityName, temp, wea));
                }
                Thread.sleep(500);
            }
        } catch (Exception e) {
            System.out.println("天气爬取失败");
        }
        return list;
    }
}

// ==================== 主程序（修复：王者英雄一定全部打印） ====================
public class CrawlerMain {
    public static void main(String[] args) {
        BaseCrawler m = new MovieCrawler();
        BaseCrawler h = new HeroCrawler();
        BaseCrawler w = new WeatherCrawler();

        // 1. 电影
        System.out.println("===== 豆瓣电影Top250 =====");
        List<Movie> movies = (List<Movie>) m.startCrawl();
        for (Movie movie : movies) {
            System.out.println(movie);
        }

        // 2. 王者英雄（一定打印出来！）
        System.out.println("\n===== 王者荣耀全英雄 =====");
        List<Hero> heroes = (List<Hero>) h.startCrawl();
        for (Hero hero : heroes) {
            System.out.println(hero);  // 这里一定会打印！
        }
        System.out.println("共爬取 " + heroes.size() + " 个英雄");

        // 3. 天气
        System.out.println("\n===== 全国各省天气 =====");
        List<Weather> weathers = (List<Weather>) w.startCrawl();
        for (Weather weather : weathers) {
            System.out.println(weather);
        }
    }
}