Learn more. How to download files to downloads folder, etc Ask Question. Asked 2 years, 3 months ago. Active 1 year, 6 months ago. Viewed 4k times. Also, I'm using Java , and not Kotlin.
Improve this question. Dalija Prasnikar Gaurav Mall Gaurav Mall 2, 1 1 gold badge 14 14 silver badges 31 31 bronze badges. YashKrishan I don't. I want to store the file in the Downloads Folder. Yes, it looks like these changes in Android Q are really bad for developers, please check also here CommonsWare's post: commonsware. Add a comment. Active Oldest Votes. Hope will help. Improve this answer. Ofiongston Ofiongston 21 3 3 bronze badges. Thanks will check this out.
I am not doing Android Development at the moment, so when I have the time I will check this out and report back. MrVasilev MrVasilev 1, 2 2 gold badges 13 13 silver badges 32 32 bronze badges. I did, but I can't understand how to implement it. An example would be great : — Gaurav Mall. GauravMall Literally, there are examples on that documentation page. The function returns the number of bytes copied. If the value of the variable i is -1, then it indicates that the contents of the file are over 2GB.
When the returned value is -1, you can use the function copyLarge inputStream, fileOS in place of the copy inputstream, fileOS function to handle this load. Both of these functions buffer the inputstream internally. The internal buffer means we do not have to use the BufferedInputStream class to enhance our code performance and helps us avoid writing boilerplate code. Another library managed by the Apache organization is the HttpComponents package.
This library uses the request-response mechanism to download the file from a given URL. The first step to downloading a file is to create an HTTP client object that would issue the request to the server. For this, we will be using the CloseableHttpClient class. The code snippet that creates a new HTTP client is as follows:. We then need to create an HttpGet or HttpPost object to send the request to the server.
The request is created by the following line of code:. The execute request function is applied to the client object and returns with a response from the server. Once the request is sent to the server we need a response object to receive the data sent from the server.
To catch the response from the server we use the HttpResponse class object. The data sent by the server in the form of a message is obtained through the getEntity function. You can also obtain the response code sent by the server through the response object and use it to your specific need.
The data to be downloaded is encapsulated within the entity object and can be extracted using the getContent function. The getContent function returns an InputStream object that can be further used with a BufferedInputStreamReader to enhance performance. Now all you need to do is read from the stream byte by byte and write the contents into a file using the FileOutputStream class. The last thing required to be done is closing all the open resources in order to ensure that the system resources are not overutilized and that there are no memory leaks.
So there you have it - these are the simplest ways to download a file using the basic Java code and other third party libraries. Now that we are done with the basics, you can be as creative as you want and utilize the knowledge to suit your needs.
Jam Malik. Optional 'thank-you' note:. So I have this question I need to get the data from the database, then insert it into excel file and download it to the user downloads folder.
So the question is do I need to create a file on some folder in my server and then in my Controller take that file and write it to another file which will be user download folder? Or should I do this? When I try to do all this staff as taking data from the database and inserting it in my excel and show the folder directly as download it does the work correctly but the problem with this method is that it doesn't show it as downloaded at the button of the browser. So can someone help me please?
Thanks in advance. Bear Bibeault. I like I'm confused, but probably because you are confused as well. Downloads have nothing to do with folders or files that you create either on the server or on the client. In your servlet where you generate the Excel content, you should just write that content to the response, and make sure that the content headers are set appropriately.
That's all you do. The browser handles all the rest of the work. You do not need to create folders on the server, you do not and in fact cannot create folders on the client.
You do it all through the response. Tim Holloway.
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