用java写的，而且是用来爬邮箱的，关于邮箱的正则只是随便写写，需要优化，仅供娱乐。

import java.io.InputStreamReader;

import java.net.URL;

import java.net.URLConnection;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

public class spider {

 public static void main(String[] args) {

  try {

   getMail();

  } catch (Exception e) {

   e.printStackTrace();

  }

 }

 public static void getMail() throws Exception {

  URL url = new URL("需要爬邮箱的网址");

  URLConnection conn = url.openConnection();

  BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()));

  

  String regex = "[a-zA-Z0-9]{6,12}@[a-zA-Z]{2,8}(\\.[a-zA-Z]{2,3}){1,2}";

  String line = null;

  while((line = in.readLine()) != null){

   Pattern p = Pattern.compile(regex);

   Matcher m = p.matcher(line);

   while(m.find()){

    System.out.println(m.group());

   }

  }

 }

}