Simulate start writing servlet response

Asked Jan 09 '13 at 15:41

Active Jun 29 '19 at 12:46

Viewed 224 times

We have a servlet that prints a server side generated Excel file to the response output stream. The Excel file is generated by a single method which returns the complete file in a POI Workbook object.

Our problem is that the method which generates the file lasts almost 30 seconds to execute. The clients keeps waiting for response all this time until we start writing the file to the response.

Is there any way to write "something" in the response to make the client navigator fire the download dialog?

Something like...

response.getOutputStream().write(null);
workbook.write(response.getOutputStream());

(Writing null in an outputStream throws a NullPointerException)

This way the download would seem to have been started although the file would be yet getting generated.

edited Jun 29 '19 at 12:46

Cœur

37,241
25
195
267

asked Jan 09 '13 at 15:41

konpai

1

Do you mean "Please wait loading page.." ? – Pradeep Simha Jan 09 '13 at 15:43
You could use a polling method but this introduces a more complicated asynchronous design. Otherwise, no. – McDowell Jan 09 '13 at 15:58
Here have some info http://stackoverflow.com/questions/6520231/how-to-force-browser-to-download-file – Marcio Junior Jan 09 '13 at 15:59
Could you setup a thread that periodically writes a zero byte array and flushes, until the workbook generation is complete and that can be streamed? – Gagravarr Jan 09 '13 at 16:28

Simulate start writing servlet response

0 Answers0