JHOVE is not an effective PDF/A validator, as detailed in this article:
http://www.pdfa.org/2014/12/ensuring-long-term-access-pdf-validation-with-jhove/
In short, it's buggy. Out of 670 invalid PDF/A files in a test suite,
it only flagged 5. It only looks for certain problems that Ghostscript
generated PDFs are unlikely to have. So use qpdf as a final check for
general ill-formed PDF problems since it is quite reliable.
JHOVE 1 is no longer maintained. There's a JHOVE 2 but it has no PDF
support. I also don't know if it's appropriate to bundle JHOVE, with an
LGPL, under this project and its current license.
Removing a dependency on Java is a huge win. A world with less Java is
a world with less AbstractFactoryConstructorInterfaces.
James R. Barlow
adf495e8cc