URL下载网络资源

1. 获取URL链接对象
2. 使用URL链接对象打开链接
3. 获取链接后获取输入流
4. 使用管道流FileOutputStream输出文件

public class URLDownloan {
    public static void main(String[] args) throws Exception {
        //获取URL地址对象
        URL url = new URL("https://m801.music.126.net/20210724172426/937f808f0880d5e1b42cace977ea5d29/jdyyaac/obj/w5rDlsOJwrLDjj7CmsOj/9879675715/aa46/c29c/bef7/cb34148aa2b1cb9fcf6b633ed7822b19.m4a");
        //通过URL对象打开连接
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
        //打开连接后获取输入流
        InputStream inputStream = urlConnection.getInputStream();
        //管道流输出文件
        FileOutputStream fileOutputStream = new FileOutputStream("变废为宝.mp3");
        //缓冲区
        byte[] bytes = new byte[1024];
        int len;
        while ((len = inputStream.read(bytes)) != -1){
            fileOutputStream.write(bytes,0,len);
        }
        //关闭流
        fileOutputStream.close();
        inputStream.close();
        urlConnection.disconnect();
    }
}

注意：使用完之后要关闭流