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.data; 18 19 import android.content.Context; 20 21 import com.android.gallery3d.common.BlobCache; 22 import com.android.gallery3d.common.BlobCache.LookupRequest; 23 import com.android.gallery3d.common.Utils; 24 import com.android.gallery3d.data.BytesBufferPool.BytesBuffer; 25 import com.android.gallery3d.util.CacheManager; 26 import com.android.gallery3d.util.GalleryUtils; 27 28 import java.io.IOException; 29 import java.nio.ByteBuffer; 30 31 public class ImageCacheService { 32 @SuppressWarnings("unused") 33 private static final String TAG = "ImageCacheService"; 34 35 private static final String IMAGE_CACHE_FILE = "imgcache"; 36 private static final int IMAGE_CACHE_MAX_ENTRIES = 5000; 37 private static final int IMAGE_CACHE_MAX_BYTES = 200 * 1024 * 1024; 38 private static final int IMAGE_CACHE_VERSION = 7; 39 40 private BlobCache mCache; 41 ImageCacheService(Context context)42 public ImageCacheService(Context context) { 43 mCache = CacheManager.getCache(context, IMAGE_CACHE_FILE, 44 IMAGE_CACHE_MAX_ENTRIES, IMAGE_CACHE_MAX_BYTES, 45 IMAGE_CACHE_VERSION); 46 } 47 48 /** 49 * Gets the cached image data for the given <code>path</code>, 50 * <code>timeModified</code> and <code>type</code>. 51 * 52 * The image data will be stored in <code>buffer.data</code>, started from 53 * <code>buffer.offset</code> for <code>buffer.length</code> bytes. If the 54 * buffer.data is not big enough, a new byte array will be allocated and returned. 55 * 56 * @return true if the image data is found; false if not found. 57 */ getImageData(Path path, long timeModified, int type, BytesBuffer buffer)58 public boolean getImageData(Path path, long timeModified, int type, BytesBuffer buffer) { 59 byte[] key = makeKey(path, timeModified, type); 60 long cacheKey = Utils.crc64Long(key); 61 try { 62 LookupRequest request = new LookupRequest(); 63 request.key = cacheKey; 64 request.buffer = buffer.data; 65 synchronized (mCache) { 66 if (!mCache.lookup(request)) return false; 67 } 68 if (isSameKey(key, request.buffer)) { 69 buffer.data = request.buffer; 70 buffer.offset = key.length; 71 buffer.length = request.length - buffer.offset; 72 return true; 73 } 74 } catch (IOException ex) { 75 // ignore. 76 } 77 return false; 78 } 79 putImageData(Path path, long timeModified, int type, byte[] value)80 public void putImageData(Path path, long timeModified, int type, byte[] value) { 81 byte[] key = makeKey(path, timeModified, type); 82 long cacheKey = Utils.crc64Long(key); 83 ByteBuffer buffer = ByteBuffer.allocate(key.length + value.length); 84 buffer.put(key); 85 buffer.put(value); 86 synchronized (mCache) { 87 try { 88 mCache.insert(cacheKey, buffer.array()); 89 } catch (IOException ex) { 90 // ignore. 91 } 92 } 93 } 94 clearImageData(Path path, long timeModified, int type)95 public void clearImageData(Path path, long timeModified, int type) { 96 byte[] key = makeKey(path, timeModified, type); 97 long cacheKey = Utils.crc64Long(key); 98 synchronized (mCache) { 99 try { 100 mCache.clearEntry(cacheKey); 101 } catch (IOException ex) { 102 // ignore. 103 } 104 } 105 } 106 makeKey(Path path, long timeModified, int type)107 private static byte[] makeKey(Path path, long timeModified, int type) { 108 return GalleryUtils.getBytes(path.toString() + "+" + timeModified + "+" + type); 109 } 110 isSameKey(byte[] key, byte[] buffer)111 private static boolean isSameKey(byte[] key, byte[] buffer) { 112 int n = key.length; 113 if (buffer.length < n) { 114 return false; 115 } 116 for (int i = 0; i < n; ++i) { 117 if (key[i] != buffer[i]) { 118 return false; 119 } 120 } 121 return true; 122 } 123 } 124