Owen Lin | a2fba68 | 2011-08-17 22:07:43 +0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2010 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.util; |
| 18 | |
Owen Lin | a2fba68 | 2011-08-17 22:07:43 +0800 | [diff] [blame] | 19 | import android.content.Context; |
| 20 | import android.content.SharedPreferences; |
| 21 | import android.preference.PreferenceManager; |
| 22 | |
Owen Lin | 73a04ff | 2012-03-14 17:27:24 +0800 | [diff] [blame] | 23 | import com.android.gallery3d.common.BlobCache; |
| 24 | |
Owen Lin | a2fba68 | 2011-08-17 22:07:43 +0800 | [diff] [blame] | 25 | import java.io.File; |
| 26 | import java.io.IOException; |
| 27 | import java.util.HashMap; |
| 28 | |
| 29 | public class CacheManager { |
| 30 | private static final String TAG = "CacheManager"; |
| 31 | private static final String KEY_CACHE_UP_TO_DATE = "cache-up-to-date"; |
| 32 | private static HashMap<String, BlobCache> sCacheMap = |
| 33 | new HashMap<String, BlobCache>(); |
| 34 | private static boolean sOldCheckDone = false; |
| 35 | |
| 36 | // Return null when we cannot instantiate a BlobCache, e.g.: |
| 37 | // there is no SD card found. |
| 38 | // This can only be called from data thread. |
| 39 | public static BlobCache getCache(Context context, String filename, |
| 40 | int maxEntries, int maxBytes, int version) { |
| 41 | synchronized (sCacheMap) { |
| 42 | if (!sOldCheckDone) { |
| 43 | removeOldFilesIfNecessary(context); |
| 44 | sOldCheckDone = true; |
| 45 | } |
| 46 | BlobCache cache = sCacheMap.get(filename); |
| 47 | if (cache == null) { |
| 48 | File cacheDir = context.getExternalCacheDir(); |
| 49 | String path = cacheDir.getAbsolutePath() + "/" + filename; |
| 50 | try { |
| 51 | cache = new BlobCache(path, maxEntries, maxBytes, false, |
| 52 | version); |
| 53 | sCacheMap.put(filename, cache); |
| 54 | } catch (IOException e) { |
| 55 | Log.e(TAG, "Cannot instantiate cache!", e); |
| 56 | } |
| 57 | } |
| 58 | return cache; |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | // Removes the old files if the data is wiped. |
| 63 | private static void removeOldFilesIfNecessary(Context context) { |
| 64 | SharedPreferences pref = PreferenceManager |
| 65 | .getDefaultSharedPreferences(context); |
| 66 | int n = 0; |
| 67 | try { |
| 68 | n = pref.getInt(KEY_CACHE_UP_TO_DATE, 0); |
| 69 | } catch (Throwable t) { |
| 70 | // ignore. |
| 71 | } |
| 72 | if (n != 0) return; |
| 73 | pref.edit().putInt(KEY_CACHE_UP_TO_DATE, 1).commit(); |
| 74 | |
| 75 | File cacheDir = context.getExternalCacheDir(); |
| 76 | String prefix = cacheDir.getAbsolutePath() + "/"; |
| 77 | |
| 78 | BlobCache.deleteFiles(prefix + "imgcache"); |
| 79 | BlobCache.deleteFiles(prefix + "rev_geocoding"); |
| 80 | BlobCache.deleteFiles(prefix + "bookmark"); |
| 81 | } |
| 82 | } |