View Javadoc

1   /*
2    * Copyright 2006-2016 The JGUIraffe Team.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License")
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *     http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package net.sf.jguiraffe.locators;
17  
18  import java.io.File;
19  import java.io.IOException;
20  import java.io.InputStream;
21  
22  /**
23   * <p>
24   * An adapter class for implementing concrete <code>Locator</code> classes.
25   * </p>
26   * <p>
27   * This class implements the <code>Locator</code> interface and provides dummy
28   * implementations for most of the methods defined in this interface. It can
29   * serve as a starting point for the implementation of custom
30   * <code>Locator</code> classes; then the developer only needs to deal with
31   * the methods that are really required.
32   * </p>
33   * <p>
34   * Because the <code>getURL()</code> method must be implemented in every
35   * locator, no dummy implementation for this method is provided.
36   * </p>
37   *
38   * @author Oliver Heger
39   * @version $Id: AbstractLocator.java 205 2012-01-29 18:29:57Z oheger $
40   */
41  public abstract class AbstractLocator implements Locator
42  {
43      /**
44       * Dummy implementation of this interface method. Always returns <b>null</b>.
45       *
46       * @return a file object for the represented resource
47       * @throws LocatorException if an error occurs
48       */
49      public File getFile() throws LocatorException
50      {
51          return null;
52      }
53  
54      /**
55       * Dummy implementation of this interface method. Always returns <b>null</b>.
56       *
57       * @return an input stream for the represented resource
58       * @throws IOException if an IO error occurs
59       * @throws LocatorException if an internal error occurs
60       */
61      public InputStream getInputStream() throws IOException, LocatorException
62      {
63          return null;
64      }
65  }