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Jasper Package Class Reference

Detailed documentation of the classes in the jasper package can be found in the HTML documentation installed with SICStus and also at the SICStus documentation page (http://www.sics.se/sicstus/docs/).

Please note: None of the se.sics.jasper methods are thread safe, unless explicitly mentioned, they can only be called from the thread that created the SICStus object. (This is different from how se.sics.jasper worked in SICStus 3.8)

However, Jasper in SICStus 3.9 and later supports multi threaded mode. Several Java threads can access SICStus runtime through a server thread that does the actual calls.

The API is defined by three interfaces: Prolog, Query and Term. The methods of these interfaces are implemented by inner classes of the Jasper server. Instances of these inner classes are returned by methods of the class Jasper and can then be used from multiple threads by the Java programmer.

In multi threaded mode the Java programmer obtains an object implementing the interface Prolog. That interface has methods similar to the methods of the SICStus class described below. Interface Query and interface Term have the same relations to class SPQuery and class SPTerm, respectively. In addition the SICStus class, the SPQuery class and the SPTerm class all implement the above interfaces. The methods of the interfaces are preferred over the old methods.

See the HTML documentation for details on the methods of the interfaces.

See Jasper Notes, for limitations in multi threaded Jasper.

HashMap varMap = new HashMap();

varMap.put("File", new SPTerm(sp, "datafile.txt"));

if (sp.query("see(File),do_something(Result),seen.", varMap)) {
   System.out.println("Result==" +
                      ((SPTerm)varMap.get("Result")).toString());
} else {
   System.out.println("Failed);
}

   ( \+ call(Module:Name(Args...)) -> fail; true )

   ( true     % just calling openQuery does not call the predicate

   ; % failing (nextSolution) will backtrack for more solutions
     call(Module:Name(Args...))
   )

The following methods are used to obtain solutions from an opened query and to tell the SICStus run-time system that no more answers are required.