Android DownFile 简单的下载文件函数

public void downloadFile1(String url,String path) {
        try{
            //下载路径，如果路径无效了，可换成你的下载路径

            final long startTime = System.currentTimeMillis();
            Log.i("DOWNLOAD","startTime="+startTime);
            //下载函数
            String filename=url.substring(url.lastIndexOf("/") + 1);
            //获取文件my
            URL myURL = new URL(url);
            URLConnection conn = myURL.openConnection();
            conn.connect();
            InputStream is = conn.getInputStream();
            int fileSize = conn.getContentLength();//根据响应获取文件大小
            if (fileSize <= 0) throw new RuntimeException("无法获知文件大小 ");
            if (is == null) throw new RuntimeException("stream is null");
            File file1 = new File(path);
            if(!file1.exists()){
                file1.mkdirs();
            }
            //把数据存入路径+文件名
            FileOutputStream fos = new FileOutputStream(path+"/"+filename);
            byte buf[] = new byte[1024];
            int downLoadFileSize = 0;
            do{
                //循环读取
                int numread = is.read(buf);
                if (numread == -1)
                {
                    break;
                }
                fos.write(buf, 0, numread);
                downLoadFileSize += numread;
                //更新进度条
            } while (true);
            Log.i("DOWNLOAD","download success");
            Log.i("DOWNLOAD","totalTime="+ (System.currentTimeMillis() - startTime));
            is.close();
        } catch (Exception ex) {
            Log.e("DOWNLOAD", "error: " + ex.getMessage(), ex);
        }
    }