Tutorial10.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package jena.examples.rdf ;

import org.apache.jena.rdf.model.*;
import org.apache.jena.util.FileManager;
import org.apache.jena.vocabulary.*;

import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;

/** Tutorial 10 - demonstrate a container
 */
public class Tutorial10 extends Object {
    
    static final String inputFileName = "vc-db-1.rdf";
    
    public static void main (String args[]) {
        // create an empty model
        Model model = ModelFactory.createDefaultModel();
       
        // use the class loader to find the input file
        InputStream in = FileManager.get().open( inputFileName );
        if (in == null) {
            throw new IllegalArgumentException( "File: " + inputFileName + " not found");
        }
        
        // read the RDF/XML file
        model.read(new InputStreamReader(in), "");
        
        // create a bag
        Bag smiths = model.createBag();
        
        // select all the resources with a VCARD.FN property
        // whose value ends with "Smith"
        StmtIterator iter = model.listStatements(
            new 
                SimpleSelector(null, VCARD.FN, (RDFNode) null) {
                    @Override
                    public boolean selects(Statement s) {
                            return s.getString().endsWith("Smith");
                    }
                });
        // add the Smith's to the bag
        while (iter.hasNext()) {
            smiths.add( iter.nextStatement().getSubject());
        }
        
        // print the graph as RDF/XML
        model.write(new PrintWriter(System.out));
        System.out.println();
        
        // print out the members of the bag
        NodeIterator iter2 = smiths.iterator();
        if (iter2.hasNext()) {
            System.out.println("The bag contains:");
            while (iter2.hasNext()) {
                System.out.println("  " +
                    ((Resource) iter2.next())
                                     .getRequiredProperty(VCARD.FN)
                                     .getString());
            }
        } else {
            System.out.println("The bag is empty");
        }
    }
}