Querying predicate in jpl and java
===

I want to make a query to use Prolog in java through JPL, I want to call a predicate like this in java:

    predicate_test([X,Y,Z]):-
         a_predicate(X),
         another_predicate(Y).
   

I make the query in java to invoque "predicate_test" like this:

       Query q4=null;
        try{
            q4 = new Query("predicate_test(Percept).");
            System.out.println(q4.query());
        }
        catch(PrologException pl){

            System.out.println(pl.getMessage());
        }

I get this message from the catch block

    PrologException: error(existence_error(predicate_test, /(schedule, 1)), context(:(system, /('$c_call_prolog', 0)), _37))

Whats wrong with my approach?

Thanks in advance
