Download a file using java

Additionally, we can specify how the copying should be done. This is demonstrated below using the try-with-resource block:. Files ; import java. In plain Java, we can read the file byte by byte from the input stream and write the bytes to a file output stream. This would translate to a simple code below:. BufferedInputStream ; import java. It is recommended to use its overloaded version with connection and read timeout parameters.

FileUtils ; import java. File ; import java. Average rating 4. Vote count: 8. No votes so far! I'm such a dufus. So the final solution for this particular use case was for the OP to simply pass the OutputStream from the StreamingOutput 's write method. The point of the downloadFile method accepting an OutputStream is so that it can write the result directly to the OutputStream provided. For instance a FileOutputStream , if you wrote it to file, while the download is coming in, it would get directly streamed to the file.

It's not meant for us to keep a reference to the OutputStream , as you were trying to do with the baos , which is where the memory realization comes in. So with the way that works, we are writing directly to the response stream provided for us. The method write doesn't actually get called until the writeTo method in the MessageBodyWriter , where the OutputStream is passed to it.

You can get a better picture looking at the MessageBodyWriter I wrote. You can see the link I provided in the earlier part of the answer, where I link to the StreamingOutputProvider.

This is exactly what happens. Pseudo code would be something like this there are a few other similar options in above mentioned post :.

Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked 6 years, 7 months ago. Active 2 months ago. Viewed k times. I have 3 machines: server where the file is located server where REST service is running Jersey client browser with access to 2nd server but no access to 1st server How can I directly without saving the file on 2nd server download the file from 1st server to client's machine?

It will work this way? There can be cases where the client need to supply some information to the HTTP server in order to download a file. As shown above, we had created a class with a main method which will propagate any occurrences of IOException back to the caller. Given that instance, we will then be able to read from the body of the HTTP response.

After we had an instance of ReadableByteChannel , we then proceed to get an instance of FileChannel that will point to a local file path where we want to save the downloaded file. In this case, we will save the downloaded file as luckyNumber. Clivant a. He owns techcoil.

IOException; import java. Active Oldest Votes. Anew 4, 1 1 gold badge 23 23 silver badges 35 35 bronze badges. Nitul Nitul 9 9 silver badges 32 32 bronze badges. Please che your code, maybe the args in the statement fileDownload args[i], args[0] ; should be swapped. Moro Moro 1, 6 6 gold badges 23 23 silver badges 34 34 bronze badges. The Overflow Blog. Podcast what if you could invest in your favorite developer? Who owns this outage?