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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *  http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.any23.extractor.rdf;
19  
20  import org.apache.any23.extractor.ExtractionResult;
21  import org.eclipse.rdf4j.model.Resource;
22  import org.eclipse.rdf4j.model.Statement;
23  import org.eclipse.rdf4j.model.IRI;
24  import org.eclipse.rdf4j.rio.RDFHandler;
25  import org.eclipse.rdf4j.rio.RDFHandlerException;
26  
27  /**
28   * An RDFHandler that relays statements and prefix definitions to an {@link ExtractionResult}. Used to feed output from
29   * Sesame's RDF parsers into Any23.
30   *
31   * @author Richard Cyganiak (richard@cyganiak.de)
32   */
33  public class RDFHandlerAdapter implements RDFHandler {
34  
35      private ExtractionResult target;
36  
37      public RDFHandlerAdapter(ExtractionResult target) {
38          this.target = target;
39      }
40  
41      public void startRDF() throws RDFHandlerException {
42      }
43  
44      public void handleNamespace(String prefix, String uri) {
45          target.writeNamespace(prefix, uri);
46      }
47  
48      public void handleStatement(Statement stmt) {
49          if (stmt != null) {
50              final Resource context = stmt.getContext();
51              if (context instanceof IRI) {
52                  target.writeTriple(stmt.getSubject(), stmt.getPredicate(), stmt.getObject(), (IRI) context);
53              } else {
54                  target.writeTriple(stmt.getSubject(), stmt.getPredicate(), stmt.getObject());
55              }
56          }
57      }
58  
59      public void handleComment(String comment) {
60          // Empty.
61      }
62  
63      public void endRDF() throws RDFHandlerException {
64          // Empty.
65      }
66  
67  }