Download generated file in Java with JavaScript/jQuery

Question

I am developing web portal, that is based on Java, JavaScript and jQuery. JavaScript communicates with Java services through JSON. I need to do this: User want to download file based on the date he choose. So I need to create hyperlink, on which user can click and the file is generated. I already have the date and the file (as a byte stream) on Java side, but I don't know how to pass this byte stream as a file to JavaScript side.

Answer 1

If I understand this correctly - you have a server process that can talk JSON to the client and vice versa.

Now the client requests a file and your return a url to the file

I suggest that url to

a) have the extension of the file type and
b) be served with the headers

Disposition: attachment; filename=filename.ext;     
Content-type: application/octet-stream

where ext is the extension

So return for example the link

/filefolder/servefile.jsp?file=page.pdf

and have

Disposition: attachment; filename=page.pdf;     
Content-type: application/octet-stream

in the server process