网络图片地址转为字节流

public class GetByteByNetUrl {
    
    /**  
     * 根据地址获得数据的字节流  
     * @param strUrl 网络连接地址  
     * @return  
     */    
    public static byte[] getImageFromNetByUrl(String strUrl){    
        try {    
            URL url = new URL(strUrl);    
            HttpURLConnection conn = (HttpURLConnection)url.openConnection();    
            conn.setRequestMethod("GET");    
            conn.setConnectTimeout(5 * 1000);    
            InputStream inStream = conn.getInputStream();//通过输入流获取图片数据    
            byte[] btImg = readInputStream(inStream);//得到图片的二进制数据    
            return btImg;    
        } catch (Exception e) {    
            e.printStackTrace();    
        }    
        return null;    
    }    
    /**  
     * 从输入流中获取数据  
     * @param inStream 输入流  
     * @return  
     * @throws Exception  
     */    
    public static byte[] readInputStream(InputStream inStream) throws Exception{    
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();    
        byte[] buffer = new byte[1024];    
        int len = 0;    
        while( (len=inStream.read(buffer)) != -1 ){    
            outStream.write(buffer, 0, len);    
        }    
        inStream.close();    
        return outStream.toByteArray();    
    }