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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  package org.apache.tika.parser;
18  
19  import java.io.IOException;
20  import java.io.InputStream;
21  
22  import org.apache.tika.exception.TikaException;
23  import org.apache.tika.metadata.Metadata;
24  import org.apache.tika.sax.BodyContentHandler;
25  import org.apache.tika.sax.TeeContentHandler;
26  import org.apache.tika.utils.RegexUtils;
27  import org.xml.sax.ContentHandler;
28  import org.xml.sax.SAXException;
29  
30  /**
31   * Parser decorator that post-processes the results from a decorated parser.
32   * The post-processing takes care of filling in the "fulltext", "summary",
33   * and "outlinks" metadata entries based on the full text content returned by
34   * the decorated parser.
35   */
36  public class ParserPostProcessor extends ParserDecorator {
37  
38      /**
39       * Creates a post-processing decorator for the given parser.
40       *
41       * @param parser the parser to be decorated
42       */
43      public ParserPostProcessor(Parser parser) {
44          super(parser);
45      }
46  
47      /**
48       * Forwards the call to the delegated parser and post-processes the
49       * results as described above.
50       */
51      public void parse(
52              InputStream stream, ContentHandler handler,
53              Metadata metadata, ParseContext context)
54              throws IOException, SAXException, TikaException {
55          ContentHandler body = new BodyContentHandler();
56          ContentHandler tee = new TeeContentHandler(handler, body);
57          super.parse(stream, tee, metadata, context);
58  
59          String content = body.toString();
60          metadata.set("fulltext", content);
61  
62          int length = Math.min(content.length(), 500);
63          metadata.set("summary", content.substring(0, length));
64  
65          for (String link : RegexUtils.extractLinks(content)) {
66              metadata.add("outlinks", link);
67          }
68      }
69  
70  }