java 代理服务器 用户名 密码 407错误

Properties systemProperties = System.getProperties();

        systemProperties.setProperty("http.proxyHost","192.168.10.240");

        systemProperties.setProperty("http.proxyPort","8080");

HttpURLConnection conn =null;

        boolean checkNext = true;

        try

        { 

            

            conn =(HttpURLConnection)new URL("http://m.weather.com.cn/data/101010900.html").openConnection();

            String encoded = new String(Base64.encode(new String("kevin.ge:hellocarel5").getBytes()));

            conn.setRequestProperty("Proxy-Authorization", "Basic " + encoded);

            int result= conn.getResponseCode(); 

            String re=conn.getResponseMessage();    

            if(result==HttpURLConnection.HTTP_OK)

            {