Re: [armedbear-devel] java/abcl hello-world example

On Sun, Aug 22, 2010 at 1:15 AM, David Dreisigmeyer david.dreisigmeyer@gmail.com wrote:

Hi Robert,

I did see that (thanks for the link).  This example is included with the source code for abcl also (in examples/lisp-to-java).  I guess what I'd need help with is how to to make a jar file from the Main.java from examples/lisp-to-java (see below) file and then use that from abcl.

Thanks again, I really appreciate it,

-Dave

import org.armedbear.lisp.*;

public class Main {    /**     * This example creates an Interpreter instance, loads our     * lisp code from a file and then looks up a function defined     * in the loaded lisp file and executes the function.     *     * The function takes a single parameter and invokes a java method     * on the object provided. We provide our Main object as the parameter.     *     */    public static void main(String[] argv)    {        try            {                Main thisObject = new Main();                Interpreter interpreter = Interpreter.createInstance();                interpreter.eval("(load "lispfunctions.lisp")");                // the function is not in a separate package, thus the                // correct package is CL-USER. Symbol names are                // upper case. Package needs the prefix, because java                // also has a class named Package.                org.armedbear.lisp.Package defaultPackage =                    Packages.findPackage("CL-USER");                Symbol voidsym =                    defaultPackage.findAccessibleSymbol("VOID-FUNCTION");                Function voidFunction = (Function) voidsym.getSymbolFunction();                voidFunction.execute(new JavaObject(thisObject));            }        catch (Throwable t)            {                System.out.println("exception!");                t.printStackTrace();            }    }    public int addTwoNumbers(int a, int b)    {        return a + b;    } }

That's independent from ABCL; it's the same as for any Java library. You need to compile the java file(s) with javac, with the libraries you need (ABCL included) on the classpath, then if you want a jar, run the jar program on the generated .class files; it has a command like syntax inspired by tar. In your case, that means something like

javac -cp .:/path/to/abcl.jar your-java-files jar cvf foo.jar .

assuming you're in a Unix-like environment and . is the source code root of your project.

For more complex scenarios - projects consisting of many files and depending on many libraries - you'll be better off using an IDE like Eclipse or a build tool like Ant.

To use your jar with ABCL, include it in the classpath:

java -cp /path/to/abcl.jar:/path/to/your.jar org.armedbear.lisp.Main

hth, Alessio Stalla