初探Java爬虫

public class spiderDemo {
    public static void main(String[] args) {
        // 爬取的目标url
        String url = "https://www.baidu.com";
        // 空字符串,用于后续接收内容
        StringBuffer result = new StringBuffer();
        BufferedReader in = null;
        try{
            // 将字符串url转换成URL类型
            URL readUrl = new URL(url);
            // 进行链接初始化
            URLConnection connection = readUrl.openConnection();
            // 开始连接
            connection.connect();
            // 创建一个输入流来读取响应内容
            in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
            // 创建读取临时变量(读取缓存)
            String tempStr = "";
            while ((tempStr = in.readLine())!=null){
                result.append(tempStr);
            }
            System.out.println(result);
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            System.out.println("爬取结束");
        }
    }
}

public static void main(String[] args) {
       SpiderDemo spiderDemo = new SpiderDemo();
       // 爬取的目标url
       String url = "https://www.baidu.com";
       // 将爬取功能封装
       String result = spiderDemo.spiderMan(url);
       // 定义样式模板,匹配<img>标签
       String patternStr = "<img.*src\\s*=\\s*(.*?)[^>]*?>";
       // 要匹配的目标字符串
       String targetStr = result;
       // 将样式模板字符串转型
       Pattern pattern = Pattern.compile(patternStr);
       // 定义匹配对象进行匹配
       Matcher matcher = pattern.matcher(targetStr);
       // 如果匹配成功
       while (matcher.find()){
           System.out.println("匹配成功");
           System.out.println(matcher.group());
       }
   }