Print When (last element reached) Expression in JasperReports

Question

Is it possible to generated a "Print When Expression" that detects the last element in an XML datasource file?

Basically I have a report with a column break inserted after a sub-report in a detail band so I can clearly define new pages for the beginning of a new record. But it always leaves me with a blank last page. So I am hoping that I can prevent this if I have a print when condition that prevents the column break if it is the last record element in the XML datasource.

Is this even possible?

Answer 1

The problem is that you don't know it's the last element until after you look for the next element. I don't think there is a simple way.

In principle it should be fine to do something like this:
Create a super-report around the entire report. Run the same query in the super-report. Count the rows. Then pass the number of rows to the original report (which is now a subreport) and re-run the query again. Clearly, running the query twice is another drawback.

If the data source were SQL, then I would suggest modifying the SQL to return the number of rows as part of the result set. But for non-SQL data sources, you need some way of knowing the number of rows (well... some way of identifying the last row) before you reach the last row.