通过http URL 获取图片流 转为字节数组

/**
     * 获取 文件 流
     * @param url
     * @return
     * @throws IOException
     */
    private byte[] getFile(String url) throws IOException{
        URL urlConet = new URL(url);
        HttpURLConnection con = (HttpURLConnection)urlConet.openConnection();    
        con.setRequestMethod("GET");    
        con.setConnectTimeout(4 * 1000);    
        InputStream inStream = con .getInputStream();    //通过输入流获取图片数据    
        ByteArrayOutputStream outStream = new ByteArrayOutputStream();    
        byte[] buffer = new byte[2048];    
        int len = 0;    
        while( (len=inStream.read(buffer)) != -1 ){    
            outStream.write(buffer, 0, len);    
        }    
        inStream.close();    
        byte[] data =  outStream.toByteArray(); 
        return data;
    }