PDForm is all-in-one debugger/viewer/mangler/deformer for your PDF files. Its goal is to support as many features of PDF 1.7 as possible. At this moment it uses Apache PDFBox for parsing and rendering, so feature-completeness of PDForm depends on feature-completeness of PDFBox, but this will change. The most annoying missing features will be added or reimplemented in PDForm separately, as obviously it isn't clearly possible to integrate some Scala code in pure Java project.
If you haven't done it, setup sbt as described in http://code.google.com/p/simple-build-tool/wiki/Setup
Then do this in PDForm's root directory
sbt update run
After that in most cases you'll see PDForm running. If not, report this as PDForm issue at http://github.com/explicitcall/PDForm/issues