Write out file through servlet

Hello all,
I wish to write out a file when a servlet is requested; however the file may be quite large and take a couple of seconds (approx 10) to write out. This results in a ten second delay for the user. I wish to offset this delay so the servlet continues executing returning the response and the file is written out in some form of background process.
Could someone point me in the right direction?
Thanks
John

Write up a Thread class to do the file writing for you. Your servlet will only start the thread with the required arguments and will generate the response without waiting for the thread to complete.

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Hi all,
I am developing an application but there is a error in my code i culdnt find so far. Can anyone help?
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I fixed it. But now it doesnt write to file and there is no error. So i cant find where am a wrong.
I send a request, it is taking string but it is not writing to file eventhough it is entering the try block.
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// for(int i=0;i<buffer.length;i++){
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Write out file through servlet

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