//      创建一个本体模型，这里使用的是前一段时间设计的IIPO本体，附带实例。

       OntModel model = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM);
       final String[] ontology = new String[] {
     "file:examples/data/university0-0.owl",
     "file:examples/data/university0-1.owl",
     "file:examples/data/university0_2.owl",
     "file:examples/data/university0_3.owl"};

       for (int j=0; j<ontology.length ;j++)
       model.read(ontology [j]);

//     创建一个查询语句

       String queryString = "PREFIX rdf:<http://www.w3.org/1999/02/22-rdf-syntax-ns#>"
           + "PREFIX ub:<http://www.lehigh.edu/~zhp2/2004/0401/univ-bench.owl#>"
           +"SELECT ?X ?Y ?Z "
           +"WHERE"
           +"{?X rdf:type ub:Student."
            + "?Y rdf:type ub:Faculty."
            + "?Z rdf:type ub:Course."
             +"?X ub:advisor ?Y."
             +"?Y ub:teacherOf ?Z."
              +"?X ub:takesCourse ?Z}";
//      创建一个查询
       Query query = QueryFactory.create(queryString);

//     执行查询，获得结果
              QueryExecution qe = QueryExecutionFactory.create(query, model);
                    ResultSet results = qe.execSelect();

//     向控制台输出结果s    

       ResultSetFormatter.out(results);
       

//     释放资源

      qe.close();

   } // the end of main.

}

结果为
-------------
| X | Y | Z |
=============
-------------
哪里出错了呢？