the class org.apache.pdfbox.pdmodel.font.PDFont occupies 8MB of space
which cannot be cleaned if PDFont.clearResources is called.
The attempt to clean the class cache therefore causes that the class is
loaded and this cache is initialized with some rubbish. I tried to
prevent to instantiate this class by usage of a hacked findLoadedClass
call to the SystemClassLoader (which is protected ...).
Now, without using the PDF parser at all, 8MB of RAM space is not
occupied, however, when the first PDF arrives this space will be taked
and never given back to GC.
WAKE UP YOU LAZY PDFBOX HACKER AND FIX THIS SHIT!