[tex4ht] java modules

[Karl Berry]

I committed the step3 changes (r725). I also inserted a variable in the
Makefile now, do_java, which enables all the Java stuff(*). It's off by
default. I figure you can run make do_java=1 for testing for now.

I changed all the bare "mkdir" calls to "mkdir -p" to avoid the useless
"File exists" diagnostics when the directory already exists.

    I am not sure whether it is OK or not as I kept the java compilation
    in the .tex system calls. Is that what you wanted ?

It was certainly a good step to replace all the hardwired paths with the
substituted paths in any case.

I guess it would be ideal to run javac from the Makefile instead of all
that crazy embedding into TeX specials, to avoid unnecessary
recompilation (it takes an awfully long time to run all that Java
stuff), but that sounds like a big job.


Meanwhile, I get two errors in the Java runs now. One is 
tex4ht-html-speech-xtpipes:

System call: pushd ./xtpipes.dir/|| exit 1 ; jar cf tex4ht.jar * ; popd ; mkdir -p ./tex4ht.dir/texmf/tex4ht/bin/|| exit 1 ; mv ./xtpipes.dir/tex4ht.jar ./tex4ht.dir/texmf/tex4ht/bin/. ; cp ./xtpipes.dir/lib/* ./tex4ht.dir/texmf/tex4ht/xtpipes/. 
~/tex/tex4ht/lit/xtpipes.dir ~/tex/tex4ht/lit
~/tex/tex4ht/lit
cp: cannot stat './xtpipes.dir/lib/*': No such file or directory
(In earlier runs, the mv also had an error there. I guess it is not
really starting from scratch.)

Another is from tex4ht-javahelp-xtpipes:
System call: pushd || exit 1 ; jar cf tex4ht.jar * ; popd ; mv tex4ht.jar ; if [ ! -d  ]; then exit 1; fi ; cp xtpipes/lib/* 
sh: line 0: pushd: no other directory
--- Warning --- System return: 256

I did not try to fix.

Thanks,
Karl