If Java is used as parent application, then things are a little more
complicated. There are a couple of things that need to be taken care
of. The first is to specify the correct class path so that Java can find
the Jasper classes (
SPTerm, and so on). This is
done by specifying the pathname of the file jasper.jar:
% java -classpath $SP_PATH/bin/jasper.jar …
SP_PATH does not need to be set; it is only used here as a
placeholder (see CPL Notes in the SICStus Prolog Manual). See the documentation of the Java implementation for
more info on how to set classpaths.
The second is to specify where Java should find the Jasper native
library (libspnative.so or spnative.dll), which the
SICStus class loads into the JVM by invoking the method
System.loadLibrary("spnative"). Under UNIX, Jasper can usually
figure this out by itself, but in the event that Jasper is used in a
non-standard installation, this will most likely fail. A typical
example of such a failure looks like:
% java -classpath […]/jasper.jar se.sics.jasper.SICStus Trying to load SICStus. Exception in thread "main" java.lang.UnsatisfiedLinkError: no spnative in java.library.path at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1133) at java.lang.Runtime.loadLibrary0(Runtime.java:470) at java.lang.System.loadLibrary(System.java:745) at se.sics.jasper.SICStus.loadNativeCode(SICStus.java:37) at se.sics.jasper.SICStus.initSICStus(SICStus.java:80) at se.sics.jasper.SICStus.<init>(SICStus.java:111) at se.sics.jasper.SICStus.main(SICStus.java:25)
Under UNIX, this can be fixed by explicitly setting the Java property
java.library.path to the location of libspnative.so, like this:
% java -Djava.library.path=/usr/local/sicstus4.5.1/lib […]
Under Windows, Java must be able to find spnative.dll through the
PATH environment variable (see Windows). Setting
-Djava.library.path under Windows
can lead to problems if multiple versions of SICStus have been installed.
If this works properly, then SICStus should have been loaded into the JVM address space.
If everything is set up correctly, then you should be able to call
(which contains a short piece of test-code) in the SICStus root class,
something like this:
% java -Djava.library.path="/usr/local/sicstus4.5.1/lib" \ -classpath "/usr/local/sicstus4.5.1/lib/sicstus-4.5.1/bin/jasper.jar" \ se.sics.jasper.SICStus Trying to load SICStus. If you see this message, then you have successfully initialized the SICStus Prolog engine.
Under Windows, it would look something like this, depending on the shell used:
% java -classpath "C:/Program Files/SICStus Prolog VC12 4.5.1/bin/jasper.jar" se.sics.jasper.SICStus Trying to load SICStus. If you see this message, then you have successfully initialized the SICStus Prolog engine.
If more than one
se.sics.jasper.SICStus instance will be created, then
the SICStus runtimes named e.g.
sprt4-5-1_instance_01_.dll need to be available as
well. See Runtime Systems on
Target Machines in the SICStus Prolog Manual.