The Apache FOP Project

The Apache™ FOP Project

Upgrading from an Earlier Version of Apache™ FOP


If you're planning to upgrade to the latest Apache™ FOP version there are a few very important things to consider:

- The new code is much more strict about the interpretation of the XSL-FO 1.1 specification. Things that worked fine in version 0.20.5 might start to produce warnings or even errors now. FOP 0.20.5 contains many bugs which have been corrected in the new code. While FOP 0.20.5 allowed you to have empty fo:table-cell elements, the new code will complain about that (unless relaxed validation is enabled) because the specification demands at least one block-level element ((%block;)+, see XSL-FO 1.1, 6.7.10) inside an fo:table-cell element.

What you need to know when you upgrade!

When you use your existing FO files or XML/XSL files which work fine with FOP version 0.20.5 against this FOP version some things may not work as expected. The following list will hopefully help you to identify and correct those problems. This does not mean that the new FOP is at fault. Quite the opposite actually! See below: