We want to generate a report that can be printed on pre-printed stationary, the layout of which can be variable depending on the customer printing the report. The height of the pre-printed letterhead is stored in the database and can be retrieved in the resultset.
It doesn't appear the height of a band can be altered after the design stage (except presumably indirectly when a text field stretches vertically). So even having access to the JasperPrint object the height of the page header band can't be altered.
What would be helpful if the height of the band (plus perhaps other properties and on other Jasper objects) could be tied to an expression as per the 'print when' expression currently does