On Ubuntu 14.04, I followed https://tex.stackexchange.com/a/44104/861.
First install pax package.
$ sudo tlmgr install pax
Then run /usr/local/texlive/2014/texmf-dist/scripts/pax/pdfannotextractor.pl --install. Note I have to specify the perl script's full path, because it isn't found otherwise. This downloads and installs PDFBox, a Java library necessary for using pax. But I had this error "Installation failed, because PDFBox library cannot be found!".
$ sudo /usr/local/texlive/2014/texmf-dist/scripts/pax/pdfannotextractor.pl --install
...
* Downloaded: $TEXMFVAR/scripts/pax/PDFBox-0.7.3.zip
Archive: $TEXMFVAR/scripts/pax/PDFBox-0.7.3.zip
inflating: $TEXMFVAR/scripts/pax/lib/PDFBox-0.7.3.jar
* Unpacked: $TEXMFVAR/scripts/pax/lib/PDFBox-0.7.3.jar
texhash: Updating /tmp/$TEXMFVAR/ls-R...
texhash: Done.
!!! Error: Installation failed, because PDFBox library cannot be found!
The perl script also creates a directory $TEXMFVAR under my current dir with following content:
$ ls \$TEXMFVAR/*
$TEXMFVAR/ls-R
$TEXMFVAR/scripts:
pax
and the pdfbox library is installed as \$TEXMFVAR/scripts/pax/lib/PDFBox-0.7.3.jar, although not found.
TEXMFVAR is used in the script pdfannotextractor.pl.
I guess the perl script doesn't find the proper value of TEXMFVAR, and /usr/local/texlive/2014/texmf-var may be the right value? Then I want to pass this value to pdfannotextractor.pl by
$ TEXMFVAR=/usr/local/texlive/2014/texmf-var sudo -E /usr/local/texlive/2014/texmf-dist/scripts/pax/pdfannotextractor.pl --install
...
* Downloaded: /usr/local/texlive/2014/texmf-var/scripts/pax/PDFBox-0.7.3.zip
Archive: /usr/local/texlive/2014/texmf-var/scripts/pax/PDFBox-0.7.3.zip
inflating: /usr/local/texlive/2014/texmf-var/scripts/pax/lib/PDFBox-0.7.3.jar
* Unpacked: /usr/local/texlive/2014/texmf-var/scripts/pax/lib/PDFBox-0.7.3.jar
texhash: Updating /usr/local/texlive/2014/texmf-var/ls-R...
texhash: Done.
!!! Error: Installation failed, because PDFBox library cannot be found!
Now it is installed to the intended directory as /usr/local/texlive/2014/texmf-var/scripts/pax/lib/PDFBox-0.7.3.jar, but still can't be found.
Thanks.