/packages/WallpaperCropper/src/com/android/gallery3d/exif/IfdData.java

  1/*
  2 * Copyright (C) 2012 The Android Open Source Project
  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
 17package com.android.gallery3d.exif;
 18
 19import java.util.HashMap;
 20import java.util.Map;
 21
 22/**
 23 * This class stores all the tags in an IFD.
 24 *
 25 * @see ExifData
 26 * @see ExifTag
 27 */
 28class IfdData {
 29
 30    private final int mIfdId;
 31    private final Map<Short, ExifTag> mExifTags = new HashMap<Short, ExifTag>();
 32    private int mOffsetToNextIfd = 0;
 33    private static final int[] sIfds = {
 34            IfdId.TYPE_IFD_0, IfdId.TYPE_IFD_1, IfdId.TYPE_IFD_EXIF,
 35            IfdId.TYPE_IFD_INTEROPERABILITY, IfdId.TYPE_IFD_GPS
 36    };
 37    /**
 38     * Creates an IfdData with given IFD ID.
 39     *
 40     * @see IfdId#TYPE_IFD_0
 41     * @see IfdId#TYPE_IFD_1
 42     * @see IfdId#TYPE_IFD_EXIF
 43     * @see IfdId#TYPE_IFD_GPS
 44     * @see IfdId#TYPE_IFD_INTEROPERABILITY
 45     */
 46    IfdData(int ifdId) {
 47        mIfdId = ifdId;
 48    }
 49
 50    static protected int[] getIfds() {
 51        return sIfds;
 52    }
 53
 54    /**
 55     * Get a array the contains all {@link ExifTag} in this IFD.
 56     */
 57    protected ExifTag[] getAllTags() {
 58        return mExifTags.values().toArray(new ExifTag[mExifTags.size()]);
 59    }
 60
 61    /**
 62     * Gets the ID of this IFD.
 63     *
 64     * @see IfdId#TYPE_IFD_0
 65     * @see IfdId#TYPE_IFD_1
 66     * @see IfdId#TYPE_IFD_EXIF
 67     * @see IfdId#TYPE_IFD_GPS
 68     * @see IfdId#TYPE_IFD_INTEROPERABILITY
 69     */
 70    protected int getId() {
 71        return mIfdId;
 72    }
 73
 74    /**
 75     * Gets the {@link ExifTag} with given tag id. Return null if there is no
 76     * such tag.
 77     */
 78    protected ExifTag getTag(short tagId) {
 79        return mExifTags.get(tagId);
 80    }
 81
 82    /**
 83     * Adds or replaces a {@link ExifTag}.
 84     */
 85    protected ExifTag setTag(ExifTag tag) {
 86        tag.setIfd(mIfdId);
 87        return mExifTags.put(tag.getTagId(), tag);
 88    }
 89
 90    protected boolean checkCollision(short tagId) {
 91        return mExifTags.get(tagId) != null;
 92    }
 93
 94    /**
 95     * Removes the tag of the given ID
 96     */
 97    protected void removeTag(short tagId) {
 98        mExifTags.remove(tagId);
 99    }
100
101    /**
102     * Gets the tags count in the IFD.
103     */
104    protected int getTagCount() {
105        return mExifTags.size();
106    }
107
108    /**
109     * Sets the offset of next IFD.
110     */
111    protected void setOffsetToNextIfd(int offset) {
112        mOffsetToNextIfd = offset;
113    }
114
115    /**
116     * Gets the offset of next IFD.
117     */
118    protected int getOffsetToNextIfd() {
119        return mOffsetToNextIfd;
120    }
121
122    /**
123     * Returns true if all tags in this two IFDs are equal. Note that tags of
124     * IFDs offset or thumbnail offset will be ignored.
125     */
126    @Override
127    public boolean equals(Object obj) {
128        if (this == obj) {
129            return true;
130        }
131        if (obj == null) {
132            return false;
133        }
134        if (obj instanceof IfdData) {
135            IfdData data = (IfdData) obj;
136            if (data.getId() == mIfdId && data.getTagCount() == getTagCount()) {
137                ExifTag[] tags = data.getAllTags();
138                for (ExifTag tag : tags) {
139                    if (ExifInterface.isOffsetTag(tag.getTagId())) {
140                        continue;
141                    }
142                    ExifTag tag2 = mExifTags.get(tag.getTagId());
143                    if (!tag.equals(tag2)) {
144                        return false;
145                    }
146                }
147                return true;
148            }
149        }
150        return false;
151    }
152}