java 解析网易邮箱里面的附件地址，获取下载地址

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.util.HashSet;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class HtmlUtils {

    public static String download_html = "http://fs.163.com/fs/display/?p=X-NETEASE-HUGE-ATTACHMENT&file=tAiok--dQS6-DVsCLRBYyI2XOe_l6T4F8OTPVps1U4pLtIVKNGH5Q2XcfF-Cypg6As-rb-qyA0G7EQ5khQc6lQ&title=%25E8%25B0%25AD%25E6%2599%25B6%25E3%2580%258A%25E4%25B9%259D%25E5%2584%25BF%25E3%2580%258B%2520-%2520%