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 17 package com.android.gallery3d.exif; 18 19 import java.util.HashMap; 20 import java.util.Map; 21 22 /** 23 * This class stores all the tags in an IFD. 24 * 25 * @see ExifData 26 * @see ExifTag 27 */ 28 class 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 */ IfdData(int ifdId)46 IfdData(int ifdId) { 47 mIfdId = ifdId; 48 } 49 getIfds()50 static protected int[] getIfds() { 51 return sIfds; 52 } 53 54 /** 55 * Get a array the contains all {@link ExifTag} in this IFD. 56 */ getAllTags()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 */ getId()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 */ getTag(short tagId)78 protected ExifTag getTag(short tagId) { 79 return mExifTags.get(tagId); 80 } 81 82 /** 83 * Adds or replaces a {@link ExifTag}. 84 */ setTag(ExifTag tag)85 protected ExifTag setTag(ExifTag tag) { 86 tag.setIfd(mIfdId); 87 return mExifTags.put(tag.getTagId(), tag); 88 } 89 checkCollision(short tagId)90 protected boolean checkCollision(short tagId) { 91 return mExifTags.get(tagId) != null; 92 } 93 94 /** 95 * Removes the tag of the given ID 96 */ removeTag(short tagId)97 protected void removeTag(short tagId) { 98 mExifTags.remove(tagId); 99 } 100 101 /** 102 * Gets the tags count in the IFD. 103 */ getTagCount()104 protected int getTagCount() { 105 return mExifTags.size(); 106 } 107 108 /** 109 * Sets the offset of next IFD. 110 */ setOffsetToNextIfd(int offset)111 protected void setOffsetToNextIfd(int offset) { 112 mOffsetToNextIfd = offset; 113 } 114 115 /** 116 * Gets the offset of next IFD. 117 */ getOffsetToNextIfd()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 equals(Object obj)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 } 153