public static String get(String uri){


                  System.setProperty("https.proxySet", "true");
      System.getProperties().put("https.proxyHost", ip);
      System.getProperties().put("https.proxyPort", port);


    Document doc = null;
    String  agent="Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko)"
        + "  Chrome/56.0.2924.87 Safari/537.36" ;
    try {
      doc = Jsoup.connect(uri).ignoreContentType(true)
          .userAgent(agent)
          // ignoreHttpErrors 
          //这个很重要 否则会报HTTP error fetching URL. Status=404
          .ignoreHttpErrors(true)  //这个很重要
          .timeout(3000).get();
    } catch (IOException e) {
      System.out.println(e.getMessage()+"  **************** get");
    }
    if (doc!=null) {
      return doc.body().text();
    }
    return null;
}