根据图片url地址获取图片的宽高

     /**
     * 根据img获取图片的宽高
     * @param img 图片地址
     * @return  图片的对象，对象中图片的真实宽高
     */ 
    public  BufferedImage getBufferedImage(String imgurl) { 
        URL url = null; 
        InputStream is = null; 
        BufferedImage img = null; 
        try { 
            url = new URL(imgurl);
            HttpURLConnection con =(HttpURLConnection)url.openConnection();
            //  设置请求头信息
            con.setRequestProperty("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:47.0) Gecko/20100101 Firefox/47.0");
            con.setRequestProperty("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8");
            con.setRequestProperty("Connection", "keep-alive");
            
            is = con.getInputStream();
            img = ImageIO.read(is); 
        } catch (MalformedURLException e) { 
            e.printStackTrace();
            log.error(e);
        } catch (Exception e) { 
            img=null;
            log.error(e);
            e.printStackTrace();
        } finally { 
            try { 
                if(is!=null){
                     is.close();     
                }
            } catch (IOException e) { 
                e.printStackTrace();
                log.error(e);
            } 
        } 
        return img; 
    }