Return Excel downloadable file from Spring

Question

So I have a Spring controller, and I\'d like to create an Excel file and return it so that it is downloaded by the browser.

I\'m using JEXcelApi.

This is m

Answer 1

You need to set the Content-Disposition header.

response.setHeader("Content-disposition","attachment; filename=" + yourFileName);

and write your bytes directly to the response OutputStream.

File xls = new File("exported.xls"); // or whatever your file is
FileInputStream in = new FileInputStream(xls);
OutputStream out = response.getOutputStream();

byte[] buffer= new byte[8192]; // use bigger if you want
int length = 0;

while ((length = in.read(buffer)) > 0){
     out.write(buffer, 0, length);
}
in.close();
out.close();

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The above is relatively old. You can construct a ResponseEntity with FileSystemResource now. A ResourceHttpMessageConverter will then copy the bytes, as I have suggested above, for you. Spring MVC makes it simpler for you rather than having you interact with interfaces from the Servlet specification.