| /* |
| * Copyright (C) 2010 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.gallery3d.util; |
| |
| import com.android.gallery3d.common.BlobCache; |
| |
| import android.content.Context; |
| import android.content.SharedPreferences; |
| import android.preference.PreferenceManager; |
| |
| import java.io.File; |
| import java.io.IOException; |
| import java.util.HashMap; |
| |
| public class CacheManager { |
| private static final String TAG = "CacheManager"; |
| private static final String KEY_CACHE_UP_TO_DATE = "cache-up-to-date"; |
| private static HashMap<String, BlobCache> sCacheMap = |
| new HashMap<String, BlobCache>(); |
| private static boolean sOldCheckDone = false; |
| |
| // Return null when we cannot instantiate a BlobCache, e.g.: |
| // there is no SD card found. |
| // This can only be called from data thread. |
| public static BlobCache getCache(Context context, String filename, |
| int maxEntries, int maxBytes, int version) { |
| synchronized (sCacheMap) { |
| if (!sOldCheckDone) { |
| removeOldFilesIfNecessary(context); |
| sOldCheckDone = true; |
| } |
| BlobCache cache = sCacheMap.get(filename); |
| if (cache == null) { |
| File cacheDir = context.getExternalCacheDir(); |
| String path = cacheDir.getAbsolutePath() + "/" + filename; |
| try { |
| cache = new BlobCache(path, maxEntries, maxBytes, false, |
| version); |
| sCacheMap.put(filename, cache); |
| } catch (IOException e) { |
| Log.e(TAG, "Cannot instantiate cache!", e); |
| } |
| } |
| return cache; |
| } |
| } |
| |
| // Removes the old files if the data is wiped. |
| private static void removeOldFilesIfNecessary(Context context) { |
| SharedPreferences pref = PreferenceManager |
| .getDefaultSharedPreferences(context); |
| int n = 0; |
| try { |
| n = pref.getInt(KEY_CACHE_UP_TO_DATE, 0); |
| } catch (Throwable t) { |
| // ignore. |
| } |
| if (n != 0) return; |
| pref.edit().putInt(KEY_CACHE_UP_TO_DATE, 1).commit(); |
| |
| File cacheDir = context.getExternalCacheDir(); |
| String prefix = cacheDir.getAbsolutePath() + "/"; |
| |
| BlobCache.deleteFiles(prefix + "imgcache"); |
| BlobCache.deleteFiles(prefix + "rev_geocoding"); |
| BlobCache.deleteFiles(prefix + "bookmark"); |
| } |
| } |