java爬虫实例-jsoup爬取豆瓣电影

添加依赖

        <!--jsoup-->
        <dependency>
            <groupId>net.databinder</groupId>
            <artifactId>dispatch-jsoup_2.8.0</artifactId>
            <version>0.8.10</version>
        </dependency>
        <!--fastJson用于解析json-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>

观察页面，发现是通过异步请求获取json，再加载到页面

首先获取全部电影链接

class GetMovie {

    //存放电影链接
    public static List<String> movieList = new ArrayList<>();

    @Test
    void contextLoads() throws IOException, InterruptedException {
        //先创建连接
        String address = "https://movie.douban.com/j/search_subjects?type=movie&tag=%E7%83%AD%E9%97%A8&sort=recommend&page_limit=10000&page_start=0";
        URL url = new URL(address);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setRequestMethod("GET");
        connection.addRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36");
        connection.setConnectTimeout(8000);
        //设置从主机读取数据超时（单位：毫秒）
        connection.setReadTimeout(8000);
        //使用jsoup解析网页
        Document parse = Jsoup.parse(connection.getInputStream(), "UTF-8", address);
        //将json转成jsonObject
        JSONObject jsonObject = JSONObject.parseObject(parse.body().text());
        JSONArray subjects = jsonObject.getJSONArray("subjects");
        for (int i = 0; i < subjects.size(); i++) {
            //获取url
            movieList.add(String.valueOf(subjects.getJSONObject(i).get("url")));
        }
        System.out.println(movieList.size());
        get(movieList);
    }

这样所有的电影url就全部获取到了，下面只需要将爬取每一个url中的信息

获取电影页面海报，主演，类型，评分等信息

 public void get(List<String> movieList) throws IOException, InterruptedException {
        List<Film> filmList = new ArrayList<>();
        for (String url : movieList) {
            URL request = new URL(url);
            HttpURLConnection connection = (HttpURLConnection) request.openConnection();
            connection.setRequestMethod("GET");
            connection.addRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36");
            connection.setConnectTimeout(8000);
            //设置从主机读取数据超时（单位：毫秒）
            connection.setReadTimeout(8000);
            Document parse = Jsoup.parse(connection.getInputStream(), "UTF-8", url);
            //获取名称
            Elements span = parse.getElementsByTag("span");
            String filmName = span.get(2).text();
            //下载图片
            Element mainpic = parse.getElementById("mainpic");
            String img = mainpic.getElementsByTag("img").attr("src");
            String[] split = url.split("/");
            String uniqueId=split[4];
            downloadImg(img, uniqueId);
            Thread.sleep(3000);
            //获取电影信息
            Film film = new Film();
            String info = parse.getElementById("info").text();
            film.setFilmType(StringUtils.substring(info,StringUtils.indexOf(info,"类型") + 3, StringUtils.indexOf(info,"制片国家")));
            film.setCountry(StringUtils.substring(info,StringUtils.indexOf(info,"制片国家") + 8, StringUtils.indexOf(info,"语言")));
            film.setReleaseTime(StringUtils.substring(info,StringUtils.indexOf(info,"上映日期") + 6, StringUtils.indexOf(info,"片长")));
            film.setFilmName(filmName);
            film.setMainActor(StringUtils.substring(info,StringUtils.indexOf(info,"主演") + 3, StringUtils.indexOf(info,"类型")));
            Elements strong = parse.getElementsByTag("strong");
            film.setScore(strong.get(0).text());
            Element intro = parse.getElementById("link-report");
            film.setFilmIntro(intro.getElementsByTag("span").text());
            film.setUniqueId(uniqueId);
            filmList.add(film);
            if(filmList.size()%50==0){
                service.batchInsert(filmList);
                filmList=new ArrayList<>();
            }

        }
    }

下载电影海报图片

/**
     * 下载图片
     *
     * @param img
     * @param filmName
     * @throws IOException
     * @throws InterruptedException
     */
    public void downloadImg(String img, String filmName) throws IOException, InterruptedException {

        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpGet httpget = new HttpGet(img);
        CloseableHttpResponse response = null;
        response = httpClient.execute(httpget);
        InputStream contentStream = response.getEntity().getContent();
        FileOutputStream out = new FileOutputStream("src\\main\\resources\\static\\img\\" + filmName + ".jpg");
        System.out.println("下载" + filmName);
        int temp;
        while ((temp = contentStream.read()) != -1) {
            out.write(temp);
        }
        out.close();
    }

下载的图片

注意：
1 请求时记得加上

connection.addRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/78.0.3904.108 Safari/537.36");

模拟浏览器访问
2 间隔3秒

Thread.sleep(3000);

这样防止被服务器当做恶意请求拒绝访问