##### Coverage Report - org.apache.any23.extractor.rdfa.RDFaExtractor

Classes in this File | Line Coverage | Branch Coverage | Complexity
RDFaExtractor |
0% | 0/37
0% | 0/4
| 1.9;1.9

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.rdfa;
19 |  |
20 |  |
     import org.apache.any23.configuration.DefaultConfiguration;
21 |  |
     import org.apache.any23.extractor.ExtractionContext;
22 |  |
     import org.apache.any23.extractor.ExtractionException;
23 |  |
     import org.apache.any23.extractor.ExtractionParameters;
24 |  |
     import org.apache.any23.extractor.ExtractionResult;
25 |  |
     import org.apache.any23.extractor.ExtractorDescription;
26 |  |
     import org.apache.any23.extractor.ExtractorFactory;
27 |  |
     import org.apache.any23.extractor.SimpleExtractorFactory;
28 |  |
     import org.apache.any23.extractor.rdf.RDFParserFactory;
29 |  |
     import org.apache.any23.extractor.Extractor.TagSoupDOMExtractor;
30 |  |
     import org.openrdf.rio.RDFHandlerException;
31 |  |
     import org.openrdf.rio.RDFParseException;
32 |  |
     import org.openrdf.rio.RDFParser;
33 |  |
     import org.w3c.dom.Document;
34 |  |
35 |  |
     import java.io.IOException;
36 |  |
     import java.io.InputStream;
37 |  |
     import java.io.StringReader;
38 |  |
     import java.io.StringWriter;
39 |  |
     import java.util.Arrays;
40 |  |
41 |  |
     /**
42 |  |
      * Extractor for RDFa in HTML, based on Fabien Gadon's XSLT transform, found
43 |  |
      * <a href="http://ns.inria.fr/grddl/rdfa/">here</a>. It works by first
44 |  |
      * parsing the HTML using a tagsoup parser, then applies the XSLT to the
45 |  |
      * DOM tree, then parses the resulting RDF/XML.
46 |  |
      *
47 |  |
      * @author Gabriele Renzi
48 |  |
      * @author Richard Cyganiak (richard@cyganiak.de)
49 |  |
      */
50 | 0 |
     public class RDFaExtractor implements TagSoupDOMExtractor {
51 |  |
52 |  |
         public final static String NAME = "html-rdfa";
53 |  |
54 | 0 |
         public final static String xsltFilename =
55 |  |
                 DefaultConfiguration.singleton().getPropertyOrFail("any23.rdfa.extractor.xslt");
56 |  |
57 | 0 |
         private static XSLTStylesheet xslt = null;
58 |  |
59 | 0 |
         public final static ExtractorFactory<RDFaExtractor> factory =
60 |  |
             SimpleExtractorFactory.create(
61 |  |
                     NAME,
62 |  |
                     null,
63 |  |
                     Arrays.asList("text/html;q=0.3", "application/xhtml+xml;q=0.3"),
64 |  |
                     null,
65 |  |
                     RDFaExtractor.class
66 |  |
             );
67 |  |
68 |  |
         /**
69 |  |
          * Returns a {@link XSLTStylesheet} able to distill RDFa from
70 |  |
          * HTML pages.
71 |  |
          *
72 |  |
          * @return returns a not <code>null</code> XSLT instance.
73 |  |
          */
74 |  |
         public static synchronized XSLTStylesheet getXSLT() {
75 |  |
             // Lazily initialized static instance, so we don't parse
76 |  |
             // the XSLT unless really necessary, and only once
77 | 0 |
             if (xslt == null) {
78 | 0 |
                 InputStream in = RDFaExtractor.class.getResourceAsStream(xsltFilename);
79 | 0 |
                 if (in == null) {
80 | 0 |
                     throw new RuntimeException("Couldn't load '" + xsltFilename +
81 |  |
                             "', maybe the file is not bundled in the jar?");
82 |  |
                 }
83 | 0 |
                 xslt = new XSLTStylesheet(in);
84 |  |
             }
85 | 0 |
             return xslt;
86 |  |
         }
87 |  |
88 |  |
         private boolean verifyDataType;
89 |  |
90 |  |
         private boolean stopAtFirstError;
91 |  |
92 |  |
         /**
93 |  |
          * Constructor, allows to specify the validation and error handling policies.
94 |  |
          *
95 |  |
          * @param verifyDataType if <code>true</code> the data types will be verified,
96 |  |
          *         if <code>false</code> will be ignored.
97 |  |
          * @param stopAtFirstError if <code>true</code> the parser will stop at first parsing error,
98 |  |
          *        if <code>false</code> will ignore non blocking errors.
99 |  |
          */
100 | 0 |
         public RDFaExtractor(boolean verifyDataType, boolean stopAtFirstError) {
101 | 0 |
             this.verifyDataType   = verifyDataType;
102 | 0 |
             this.stopAtFirstError = stopAtFirstError;
103 | 0 |
         }
104 |  |
105 |  |
         /**
106 |  |
          * Default constructor, with no verification of data types and not stop at first error.
107 |  |
          */
108 |  |
         public RDFaExtractor() {
109 | 0 |
             this(false, false);
110 | 0 |
         }
111 |  |
112 |  |
         public boolean isVerifyDataType() {
113 | 0 |
             return verifyDataType;
114 |  |
         }
115 |  |
116 |  |
         public void setVerifyDataType(boolean verifyDataType) {
117 | 0 |
             this.verifyDataType = verifyDataType;
118 | 0 |
         }
119 |  |
120 |  |
         public boolean isStopAtFirstError() {
121 | 0 |
             return stopAtFirstError;
122 |  |
         }
123 |  |
124 |  |
         public void setStopAtFirstError(boolean stopAtFirstError) {
125 | 0 |
             this.stopAtFirstError = stopAtFirstError;
126 | 0 |
         }
127 |  |
128 |  |
         public void run(
129 |  |
                 ExtractionParameters extractionParameters,
130 |  |
                 ExtractionContext extractionContext,
131 |  |
                 Document in,
132 |  |
                 ExtractionResult out
133 |  |
         ) throws IOException, ExtractionException {
134 |  |
135 | 0 |
             StringWriter buffer = new StringWriter();
136 |  |
             try {
137 | 0 |
                 getXSLT().applyTo(in, buffer);
138 | 0 |
             } catch (XSLTStylesheetException xslte) {
139 | 0 |
                 throw new ExtractionException("An error occurred during the XSLT application.", xslte);
140 | 0 |
             }
141 |  |
142 |  |
             try {
143 | 0 |
                 RDFParser parser
144 |  |
                         = RDFParserFactory.getInstance().getRDFXMLParser(
145 |  |
                             verifyDataType, stopAtFirstError, extractionContext, out
146 |  |
                         );
147 | 0 |
                 parser.parse(
148 |  |
                         new StringReader(buffer.getBuffer().toString()),
149 |  |
                         extractionContext.getDocumentURI().stringValue()
150 |  |
                 );
151 | 0 |
             } catch (RDFHandlerException ex) {
152 | 0 |
                 throw new IllegalStateException(
153 |  |
                         "Should not happen, RDFHandlerAdapter does not throw RDFHandlerException", ex
154 |  |
                 );
155 | 0 |
             } catch (RDFParseException ex) {
156 | 0 |
                 throw new ExtractionException(
157 |  |
                         "Invalid RDF/XML produced by RDFa transform.", ex, out
158 |  |
                 );
159 | 0 |
             }
160 | 0 |
         }
161 |  |
162 |  |
         private String getDocType(Document in) {
163 | 0 |
             return in.getDoctype().getPublicId();
164 |  |
         }
165 |  |
166 |  |
         /**
167 |  |
          * @return the {@link org.apache.any23.extractor.ExtractorDescription} of this extractor
168 |  |
          */
169 |  |
         public ExtractorDescription getDescription() {
170 | 0 |
             return factory;
171 |  |
         }
172 |  |
173 |  |
     }