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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.xpath;
19  
20  import org.eclipse.rdf4j.model.Value;
21  import org.eclipse.rdf4j.model.impl.SimpleValueFactory;
22  
23  /**
24   * Represents a <i>Quad</i> object <i>template</i>.
25   *
26   * @author Michele Mostarda (mostarda@fbk.eu)
27   */
28  public class TemplateObject extends Term {
29  
30      /**
31       * Supported object types.
32       */
33      public enum Type {
34          URI,
35          BNODE,
36          LITERAL
37      }
38  
39      /**
40       * Current template type.
41       */
42      private final Type type;
43  
44      /**
45       * Constructor.
46       *
47       * @param type object template type.
48       * @param value internal value.
49       * @param isVar if <code>true</code> it the given <code>value</code>
50       *              will be resolved with the variable value.
51       */
52      public TemplateObject(Type type, String value, boolean isVar) {
53          super(value, isVar);
54          if (type == null) {
55              throw new NullPointerException("object type cannot be null.");
56          }
57          this.type = type;
58      }
59  
60      @Override
61      protected Value getValueInternal(String value) {
62          switch (type) {
63              case URI:
64                  return createIRI(value);
65              case BNODE:
66                  return SimpleValueFactory.getInstance().createBNode(value);
67              case LITERAL:
68                  return SimpleValueFactory.getInstance().createLiteral(value);
69              default:
70                  throw new IllegalStateException();
71          }
72      }
73  
74      private Value createIRI(String value) {
75          try {
76              return SimpleValueFactory.getInstance().createIRI(value);
77          } catch (IllegalArgumentException iae) {
78              throw new IllegalArgumentException(
79                  String.format("Expected a valid IRI for object template, found '%s'", value),
80                  iae
81              );
82          }
83      }
84  
85      @Override
86      public String toString() {
87          final String superStr = super.toString();
88          switch (type) {
89              case URI:
90                  return "<" + superStr + ">";
91              case BNODE:
92                  return "_:" + superStr;
93              case LITERAL:
94                  return "'" + superStr + "'";
95              default:
96                  throw new IllegalStateException();
97          }
98      }
99  
100 }