I am considering building a financial application using Java SE and a
database back-end. The only area of concern for me is how I would produce
letters or reports with the Java application.

I would like the application to be able to produce letters which will be
automatically printed out (to be sent out to customers). I would also like
to be able to produce attractive reports which management staff can print
out.

For example, if MS Access is used, it has a very simple built-in "reports"
feature which can produce nice reports and letters. Obviously something like
Crystal Reports would be an option but that doesn't fit in with the
cost-model of this application due to license costs. HTML is an option, but
I'm not sure how easily this can interface with the Java application and
produce data-merged letters.

Does anyone have any suggestions as to what I can use?