java根据url下载文件以及从InputStream内读二进制数组

版权声明：本文为博主原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。

本文链接： https://blog.csdn.net/wanghaichuan19970322/article/details/102779462

URL url = new URL(fileUrl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5000);
conn.setReadTimeout(60000);
inputStream = conn.getInputStream();

inputStream 为根据url读取的文件输入流

使用以下方法可以的得到文件的二进制数组

private byte[] read(InputStream inputStream) {
        ByteArrayOutputStream baos = null;
        try {
            baos = new ByteArrayOutputStream();
            byte[] buffer = new byte[1024];
            int num = inputStream.read(buffer);
            while (num != -1) {
                baos.write(buffer, 0, num);
                num = inputStream.read(buffer);
            }
            baos.flush();
            return baos.toByteArray();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (baos != null) {
                try {
                    baos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        return null;
    }