Dynamic Show/Hide fields in Jasper

Hi There,

I am able to do reports in Jasper.  My requirement is such that if there is no value for a column in my report that column should not be shown.  I have used "Print when Expression" for that column and hidden it successfully.

But how do I make the column width to be used by other fields if it is not shown.  I was searching for how I can achieve this in the internet.  Lot of them have mentioned about Dynamic Template generation or compilation.  But I don't know how to do this dynamically.  Can anyone help me with a sample regarding this?

Regards
Krish