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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.html;
    19
    20  import org.apache.any23.extractor.ExtractionContext;
    21  import org.apache.any23.extractor.ExtractionException;
    22  import org.apache.any23.extractor.ExtractionParameters;
    23  import org.apache.any23.extractor.ExtractionResult;
    24  import org.apache.any23.extractor.ExtractorDescription;
    25  import org.apache.any23.rdf.Any23ValueFactoryWrapper;
    26  import org.apache.any23.extractor.Extractor.TagSoupDOMExtractor;
    27  import org.eclipse.rdf4j.model.BNode;
    28  import org.eclipse.rdf4j.model.IRI;
    29  import org.eclipse.rdf4j.model.ValueFactory;
    30  import org.eclipse.rdf4j.model.impl.SimpleValueFactory;
    31  import org.w3c.dom.Document;
    32
    33  import java.io.IOException;
    34
    35  /**
    36   * Extractor for "ICBM coordinates" provided as META headers in the head of an HTML page.
    37   *
    38   * @author Gabriele Renzi
    39   * @author Richard Cyganiak (richard@cyganiak.de)
    40   */
    41  public class ICBMExtractor implements TagSoupDOMExtractor {
    42
    43      @Override
    44      public void run(ExtractionParameters extractionParameters, ExtractionContext extractionContext, Document in,
    45              ExtractionResult out) throws IOException, ExtractionException {
    46
    47          // ICBM is the preferred method, if two values are available it is meaningless to read both
    48          String props = DomUtils.find(in, "//META[@name=\"ICBM\" or @name=\"geo.position\"]/@content");
    49          if ("".equals(props))
    50              return;
    51
    52          String[] coords = props.split("[;,]");
    53          float lat, lon;
    54          try {
    55              lat = Float.parseFloat(coords[0]);
    56              lon = Float.parseFloat(coords[1]);
    57          } catch (NumberFormatException nfe) {
    58              return;
    59          }
    60
    61          final ValueFactory factory = new Any23ValueFactoryWrapper(SimpleValueFactory.getInstance(), out);
    62          BNode point = factory.createBNode();
    63          out.writeTriple(extractionContext.getDocumentIRI(), expand("dcterms:related"), point);
    64          out.writeTriple(point, expand("rdf:type"), expand("geo:Point"));
    65          out.writeTriple(point, expand("geo:lat"), factory.createLiteral(Float.toString(lat)));
    66          out.writeTriple(point, expand("geo:long"), factory.createLiteral(Float.toString(lon)));
    67      }
    68
    69      private IRI expand(String curie) {
    70          return getDescription().getPrefixes().expand(curie);
    71      }
    72
    73      @Override
    74      public ExtractorDescription getDescription() {
    75          return ICBMExtractorFactory.getDescriptionInstance();
    76      }
    77
    78  }