Winson | 9947f1e | 2019-08-16 10:20:39 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2019 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 android.content.res.loader; |
| 18 | |
| 19 | import android.annotation.Nullable; |
| 20 | import android.content.res.ApkAssets; |
| 21 | import android.content.res.AssetManager; |
| 22 | import android.content.res.Resources; |
| 23 | import android.content.res.ResourcesImpl; |
| 24 | import android.util.Pair; |
| 25 | |
| 26 | import com.android.internal.annotations.GuardedBy; |
| 27 | import com.android.internal.util.ArrayUtils; |
| 28 | |
| 29 | import java.util.ArrayList; |
| 30 | import java.util.List; |
| 31 | import java.util.Objects; |
| 32 | |
| 33 | /** |
| 34 | * @hide |
| 35 | */ |
| 36 | public class ResourceLoaderManager { |
| 37 | |
| 38 | private final Object mLock = new Object(); |
| 39 | |
| 40 | @GuardedBy("mLock") |
| 41 | private final List<Pair<ResourceLoader, ResourcesProvider>> mResourceLoaders = |
| 42 | new ArrayList<>(); |
| 43 | |
| 44 | @GuardedBy("mLock") |
| 45 | private ResourcesImpl mResourcesImpl; |
| 46 | |
| 47 | public ResourceLoaderManager(ResourcesImpl resourcesImpl) { |
| 48 | this.mResourcesImpl = resourcesImpl; |
| 49 | this.mResourcesImpl.getAssets().setResourceLoaderManager(this); |
| 50 | } |
| 51 | |
| 52 | /** |
| 53 | * Copies the list to ensure that ongoing mutations don't affect the list if it's being used |
| 54 | * as a search set. |
| 55 | * |
| 56 | * @see Resources#getLoaders() |
| 57 | */ |
| 58 | public List<Pair<ResourceLoader, ResourcesProvider>> getLoaders() { |
| 59 | synchronized (mLock) { |
| 60 | return new ArrayList<>(mResourceLoaders); |
| 61 | } |
| 62 | } |
| 63 | |
| 64 | /** |
| 65 | * Returns a list for searching for a loader. Locks and copies the list to ensure that |
| 66 | * ongoing mutations don't affect the search set. |
| 67 | */ |
| 68 | public List<Pair<ResourceLoader, ResourcesProvider>> getInternalList() { |
| 69 | synchronized (mLock) { |
| 70 | return new ArrayList<>(mResourceLoaders); |
| 71 | } |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * TODO(b/136251855): Consider optional boolean ignoreConfigurations to allow ResourceLoader |
| 76 | * to override every configuration in the target package |
| 77 | * |
| 78 | * @see Resources#addLoader(ResourceLoader, ResourcesProvider) |
| 79 | */ |
| 80 | public void addLoader(ResourceLoader resourceLoader, ResourcesProvider resourcesProvider, |
| 81 | int index) { |
| 82 | synchronized (mLock) { |
| 83 | for (int listIndex = 0; listIndex < mResourceLoaders.size(); listIndex++) { |
| 84 | if (Objects.equals(mResourceLoaders.get(listIndex).first, resourceLoader)) { |
| 85 | throw new IllegalArgumentException("Cannot add the same ResourceLoader twice"); |
| 86 | } |
| 87 | } |
| 88 | |
| 89 | mResourceLoaders.add(index, Pair.create(resourceLoader, resourcesProvider)); |
| 90 | updateLoaders(); |
| 91 | } |
| 92 | } |
| 93 | |
| 94 | /** |
| 95 | * @see Resources#removeLoader(ResourceLoader) |
| 96 | */ |
| 97 | public int removeLoader(ResourceLoader resourceLoader) { |
| 98 | synchronized (mLock) { |
| 99 | int indexOfLoader = -1; |
| 100 | |
| 101 | for (int index = 0; index < mResourceLoaders.size(); index++) { |
| 102 | if (mResourceLoaders.get(index).first == resourceLoader) { |
| 103 | indexOfLoader = index; |
| 104 | break; |
| 105 | } |
| 106 | } |
| 107 | |
| 108 | if (indexOfLoader < 0) { |
| 109 | return indexOfLoader; |
| 110 | } |
| 111 | |
| 112 | mResourceLoaders.remove(indexOfLoader); |
| 113 | updateLoaders(); |
| 114 | return indexOfLoader; |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | /** |
| 119 | * @see Resources#setLoaders(List) |
| 120 | */ |
| 121 | public void setLoaders( |
| 122 | @Nullable List<Pair<ResourceLoader, ResourcesProvider>> newLoadersAndProviders) { |
| 123 | synchronized (mLock) { |
| 124 | if (ArrayUtils.isEmpty(newLoadersAndProviders)) { |
| 125 | mResourceLoaders.clear(); |
| 126 | updateLoaders(); |
| 127 | return; |
| 128 | } |
| 129 | |
| 130 | int size = newLoadersAndProviders.size(); |
| 131 | for (int newIndex = 0; newIndex < size; newIndex++) { |
| 132 | ResourceLoader resourceLoader = newLoadersAndProviders.get(newIndex).first; |
| 133 | for (int oldIndex = 0; oldIndex < mResourceLoaders.size(); oldIndex++) { |
| 134 | if (Objects.equals(mResourceLoaders.get(oldIndex).first, resourceLoader)) { |
| 135 | throw new IllegalArgumentException( |
| 136 | "Cannot add the same ResourceLoader twice"); |
| 137 | } |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | mResourceLoaders.clear(); |
| 142 | mResourceLoaders.addAll(newLoadersAndProviders); |
| 143 | |
| 144 | updateLoaders(); |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | /** |
| 149 | * Swap the tracked {@link ResourcesImpl} and reattach any loaders to it. |
| 150 | */ |
| 151 | public void onImplUpdate(ResourcesImpl resourcesImpl) { |
| 152 | synchronized (mLock) { |
| 153 | this.mResourcesImpl = resourcesImpl; |
Winson | c932ff2 | 2019-12-05 16:42:54 -0800 | [diff] [blame] | 154 | this.mResourcesImpl.getAssets().setResourceLoaderManager(this); |
Winson | 9947f1e | 2019-08-16 10:20:39 -0700 | [diff] [blame] | 155 | updateLoaders(); |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | private void updateLoaders() { |
| 160 | synchronized (mLock) { |
| 161 | AssetManager assetManager = mResourcesImpl.getAssets(); |
| 162 | ApkAssets[] existingApkAssets = assetManager.getApkAssets(); |
| 163 | int baseApkAssetsSize = 0; |
| 164 | for (int index = existingApkAssets.length - 1; index >= 0; index--) { |
| 165 | // Loaders are always last, so the first non-loader is the end of the base assets |
| 166 | if (!existingApkAssets[index].isForLoader()) { |
| 167 | baseApkAssetsSize = index + 1; |
| 168 | break; |
| 169 | } |
| 170 | } |
| 171 | |
| 172 | List<ApkAssets> newAssets = new ArrayList<>(); |
| 173 | for (int index = 0; index < baseApkAssetsSize; index++) { |
| 174 | newAssets.add(existingApkAssets[index]); |
| 175 | } |
| 176 | |
| 177 | int size = mResourceLoaders.size(); |
| 178 | for (int index = 0; index < size; index++) { |
| 179 | ApkAssets apkAssets = mResourceLoaders.get(index).second.getApkAssets(); |
| 180 | newAssets.add(apkAssets); |
| 181 | } |
| 182 | |
| 183 | assetManager.setApkAssets(newAssets.toArray(new ApkAssets[0]), true); |
| 184 | |
| 185 | // Short of resolving every resource, it's too difficult to determine what has changed |
| 186 | // when a resource loader is changed, so just clear everything. |
| 187 | mResourcesImpl.clearAllCaches(); |
| 188 | } |
| 189 | } |
| 190 | } |