[armedbear-devel] Several ABCL/Java questions

[Didier Verna]

Alessio Stalla <alessiostalla at gmail.com> wrote:

> You do need one. You can either use ABCL's one - in that case you have
> to pass something like --eval "(your-main-function)", perhaps with a
> shell script - or write a custom one in Java that will call the right
> Lisp function.

Here's the closest thing I have to "standalone" ABCL executables so far. 
Comments welcome (remember: I don't know Java).

Main.java:

| import org.armedbear.lisp.*;
| 
| public class Main
| {
|     public static void main (String[] argv)
|     {
| 	try
| 	    {
| 		LispObject cmdline = Lisp.NIL;
| 		for (String arg : argv)
| 		    cmdline = new Cons (arg, cmdline);
| 		cmdline.nreverse ();
| 		Lisp._COMMAND_LINE_ARGUMENT_LIST_.setSymbolValue (cmdline);
| 
| 		Interpreter interpreter = Interpreter.createInstance ();
| 		// load a lisp file like main.lisp or so.
| 	    }
| 	catch (Throwable t)
| 	    {
| 		t.printStackTrace ();
| 	    }
|     }
| }

javac -cp /usr/local/pkg/common-lisp/abcl/\*  Main.java
java  -cp /usr/local/pkg/common-lisp/abcl/\*:. Main [options...]

And now from that interpreter (in fact, its #'main function),
*command-line-argument-list* contains the list of [options...], with the
notable effect that none of them are processed by, or affect ABCL
itself.


Two remarks:

- I can also provide my own jar file, only it seems painful to do
  because I would have to uncompress abcl.jar to get all its contents
  and then create my own by adding Main.class to it. I've seen threads
  dating back to 2007 about adding jar files to jar files directly but
  it seems that it still doesn't work the way I want it to (accessing
  the sub-jar's contents). Correct?

- A cleaner way to do the above would have been to extend the
  Interpreter class by adding a new method, e.g. createStandaloneInstance,
  as a mixture of createDefaultInstance and createInstance. Unfortunately,
  this is not possible because this class is final.

-- 
Resistance is futile. You will be jazzimilated.

Scientific site:   http://www.lrde.epita.fr/~didier
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