What is that? Googling ersatz gcj gives your comment as the only relevant result. Also GCJ is/was a Java compiler as far as I am aware.

pdftk is a sort-of-C++ program that contains code like:

  #include "pdftk/com/lowagie/text/pdf/PdfReader.h"
  ...
                  if( input_pdf_p->m_password.empty() ) {
                        reader= new itext::PdfReader( JvNewStringUTF( input_pdf_p->m_filename.c_str() ) );

PdfReader is actually java/pdftk/com/lowagie/text/pdf/PdfReader.java in the pdftk source distribution. Yes, this is a C++ program that's instantiating a Java class. As far as I can tell, what's actually going on is that all the Java code is compiled to C++-ABI-compatible .o files using GCJ and pdftk.cc links against them, giving a native program that is nonetheless mostly written in Java. Yikes!

Perhaps unsurprisingly, GCJ didn't get a huge amount of traction, and it has been deleted from the GCC tree entirely. Good riddance, maybe, but it makes it rather difficult to compile pdftk.

Someone should port all that C++ code (there's not that much of it, really) to Java, that would make it a lot easier to compile, wouldn't it?

>ersatz >ˈəːsats,ˈɛːsats/ >adjective >(of a product) made or used as a substitute, typically an inferior one, for something else.