java实现http下载

/**
	 * 通过http下载文件
	 * @param destUrl http文件路径
	 * @param fileName 保存的文件路径
	 * @throws IOException
	 */
	public static void downFile(String destUrl, String fileName) throws IOException {
		log.info("start down " + destUrl);
        FileOutputStream fos = null;
        BufferedInputStream bis = null;
        HttpURLConnection httpUrl = null;
        URL url = null;
        byte[] buf = new byte[1024];
        int size = 0;
        
        url = new URL(destUrl);
        httpUrl = (HttpURLConnection) url.openConnection();
        httpUrl.connect();
        bis = new BufferedInputStream(httpUrl.getInputStream());
        fos = new FileOutputStream(fileName);
        while ((size = bis.read(buf)) != -1)
            fos.write(buf, 0, size);
        fos.close();
        bis.close();
        httpUrl.disconnect();
        log.info("downfile success ,filename : " + fileName);
    }