1/*
2 * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25package javax.imageio.plugins.tiff;
26
27import java.util.ArrayList;
28import java.util.List;
29
30/**
31 * A class containing the TIFF tags used to reference the Exif and GPS IFDs.
32 * This tag set should be added to the root tag set by means of the
33 * {@link TIFFImageReadParam#addAllowedTagSet(TIFFTagSet)
34 * TIFFImageReadParam.addAllowedTagSet} method if Exif
35 * support is desired.
36 *
37 * @since 9
38 */
39public final class ExifParentTIFFTagSet extends TIFFTagSet {
40
41    private static ExifParentTIFFTagSet theInstance = null;
42
43    // 34665 - Exif IFD Pointer                   (LONG/1)
44    /** Tag pointing to the Exif IFD (type LONG). */
45    public static final int TAG_EXIF_IFD_POINTER = 34665;
46
47    /** Tag pointing to a GPS info IFD (type LONG). */
48    public static final int TAG_GPS_INFO_IFD_POINTER = 34853;
49
50    // To be inserted into parent (root) TIFFTagSet
51    static class ExifIFDPointer extends TIFFTag {
52
53        public ExifIFDPointer() {
54            super("ExifIFDPointer",
55                  TAG_EXIF_IFD_POINTER,
56                  ExifTIFFTagSet.getInstance());
57        }
58    }
59
60    // To be inserted into parent (root) TIFFTagSet
61    static class GPSInfoIFDPointer extends TIFFTag {
62
63        public GPSInfoIFDPointer() {
64            super("GPSInfoIFDPointer",
65                  TAG_GPS_INFO_IFD_POINTER,
66                  ExifGPSTagSet.getInstance());
67        }
68    }
69
70    private static List<TIFFTag> tags;
71
72    private static void initTags() {
73        tags = new ArrayList<TIFFTag>(1);
74        tags.add(new ExifParentTIFFTagSet.ExifIFDPointer());
75        tags.add(new ExifParentTIFFTagSet.GPSInfoIFDPointer());
76    }
77
78    private ExifParentTIFFTagSet() {
79        super(tags);
80    }
81
82    /**
83     * Returns a shared instance of an {@code ExifParentTIFFTagSet}.
84     *
85     * @return an {@code ExifParentTIFFTagSet} instance.
86     */
87    public synchronized static ExifParentTIFFTagSet getInstance() {
88        if (theInstance == null) {
89            initTags();
90            theInstance = new ExifParentTIFFTagSet();
91            tags = null;
92        }
93        return theInstance;
94    }
95}
96