View Javadoc

1   /* This file is part of COPAL (COntext Provisioning for All).
2    *
3    * COPAL is a part of SM4All (Smart hoMes for All) project.
4    *
5    * COPAL is free software: you can redistribute it and/or modify
6    * it under the terms of the GNU Lesser General Public License as published by
7    * the Free Software Foundation, either version 3 of the License, or
8    * (at your option) any later version.
9    *
10   * COPAL is distributed in the hope that it will be useful,
11   * but WITHOUT ANY WARRANTY; without even the implied warranty of
12   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   * GNU Lesser General Public License for more details.
14   *
15   * You should have received a copy of the GNU Lesser General Public License
16   * along with COPAL. If not, see <http://www.gnu.org/licenses/>.
17   */
18  package at.ac.tuwien.infosys.sm4all.copal.api.event.xml.type;
19  
20  import org.w3c.dom.Element;
21  import at.ac.tuwien.infosys.sm4all.copal.api.event.xml.XMLContextEventType;
22  import at.ac.tuwien.infosys.sm4all.copal.api.xml.Marshaller;
23  import at.ac.tuwien.infosys.sm4all.copal.api.xml.OptionalAttributeUnmarshaller;
24  
25  /**
26   * Command that marshalls and unmarshalls root element name of a
27   * {@link XMLContextEventType} into/from an {@link Element}.
28   * 
29   * @author sanjin
30   */
31  public class RootElement extends OptionalAttributeUnmarshaller<String>
32          implements Marshaller<XMLContextEventType> {
33  
34      private static final String ROOT_ELEMENT_NAME_ATTRIBUTE = "rootElement";
35  
36      private final Element element;
37  
38      /**
39       * Creates instance of {@link XMLContextEventType} root element name
40       * marshaller and unmarshaller which uses specified {@link Element} to
41       * marshal and/or unmarshal the root element name.
42       * 
43       * @param element the {@link Element} used for marshalling and
44       *        unmarshalling.
45       * @throws NullPointerException if specified {@link Element} is
46       *         <code>null</code>.
47       */
48      public RootElement(final Element element) {
49          super(element, ROOT_ELEMENT_NAME_ATTRIBUTE);
50  
51          this.element = element;
52      }
53  
54      @Override
55      protected String valueOf(final String value) {
56          return value;
57      }
58  
59      /**
60       * Sets the <code>rootElement</code> attribute of specified {@link Element}
61       * to root element name of specified {@link XMLContextEventType}.
62       * 
63       * @param eventType the {@link XMLContextEventType}.
64       * @throws NullPointerException if specified {@link XMLContextEventType} is
65       *         <code>null</code>.
66       */
67      @Override
68      public void marshal(final XMLContextEventType eventType) {
69          if (eventType == null)
70              throw new NullPointerException("Event type cannot be null.");
71  
72          if (!eventType.getName().equals(eventType.getRootElementName()))
73              this.element.setAttribute(ROOT_ELEMENT_NAME_ATTRIBUTE,
74                      eventType.getRootElementName());
75      }
76  }