ProgramaticLuceneQueryAccess

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This note will describe how to programatically

  • generate phonetic lucene indicies for an ontology
  • make a phonetic query that uses the lucene indicies and
  • save the project to include the lucene query tab.

I will assume that you have already obtained the binary or src (http://smi-protege/repos/protege/lucene-query/trunk) for the lucene query plugin. The code for this example can be downloaded from here. The test code I used had the following structure:

    @SuppressWarnings("unchecked")
    public static void main(String args[]) {
        List errors = new ArrayList();
        Project project = new Project(PROJECT_FILE, errors);
        displayErrors(errors);
        OWLModel om = (OWLModel) project.getKnowledgeBase();

        indexOntology(om);
        testQuery(om);
        addTab(project);
    }

The first few lines just illustrate one of the standard ways of opening an ontology in Protege. This test code was set up to work with the pizza project but it could easily be modified to fit other ontologies. The last three lines show the code that we will explain here.

First we index the ontology. This is done by the indexOntology routine and the code looks like this:

    private static void indexOntology(KnowledgeBase kb) {
        QueryApi api = new QueryApi(kb);
        QueryConfiguration config = new QueryConfiguration(kb);
        
        alterConfiguration(kb, config);
        
        api.install(config);
        api.index();
    }

This code uses the QueryApi and the QueryConfiguration classes in the edu.stanford.smi.protege.query.api package. Before installing the query capability into the knowledge base we perform the optional step of configuring the slots indexed, the location of the indicies and the types of queries supported:

    private static void alterConfiguration(KnowledgeBase kb, QueryConfiguration config) {
        config.setBaseIndexPath("/tmp/lucene");
        Set<Indexer> indexers = new HashSet<Indexer>();
        indexers.add(new PhoneticIndexer());
        config.setIndexers(indexers);
        Set<Slot> slots = new HashSet<Slot>();
        slots.add(kb.getSystemFrames().getNameSlot());
    }

Now that we have indexed the ontology, we can do a programatic query. This is done in the following code:

    private static void testQuery(KnowledgeBase kb) {
        Slot slot = kb.getSystemFrames().getNameSlot();
        Set<Frame> results = null;
        results = kb.executeQuery(new PhoneticQuery(slot, "sheazeypeasah"));
        if (results == null || results.size() != 1) {
            System.out.println("test of search failed");
        }
        else {
            System.out.println("Search succeeded (" + results.iterator().next().getBrowserText() + ")");
        }
    }

There are several types of queries (some of which are composed out of other queries) defined in the lucene query plugin including:

  • conjuctions and disjunctions of queries,
  • queries that can only return a limited set of results,
  • queries that find regular expression matches for a slot value,
  • queries that match slot values with the results of a nested query and
  • queries that look inside a restriction for matches to an inner query.

Finally we add the lucene plugin as a tab to the project. I was not quite able to use the code suggested in Adding and removing tabs programmatically because when I retrieved the project view it was null. The code is as follows:

   @SuppressWarnings("unchecked")
    private static void addTab(Project project) {
        List errors = new ArrayList();
        
        WidgetDescriptor tabWidgetDescriptor = project.getTabWidgetDescriptor("edu.stanford.smi.protege.query.LuceneQueryPlugin");
        tabWidgetDescriptor.setVisible(true);

        Collection widgets = project.getTabWidgetDescriptors();
        project.setTabWidgetDescriptorOrder(widgets);
        
        project.save(errors);
        displayErrors(errors);
    }