diff options
Diffstat (limited to 'src/com/android/gallery3d/data/ImageCacheService.java')
-rw-r--r-- | src/com/android/gallery3d/data/ImageCacheService.java | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/src/com/android/gallery3d/data/ImageCacheService.java b/src/com/android/gallery3d/data/ImageCacheService.java new file mode 100644 index 000000000..1c7cb8c5e --- /dev/null +++ b/src/com/android/gallery3d/data/ImageCacheService.java @@ -0,0 +1,123 @@ +/* + * 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.data; + +import android.content.Context; + +import com.android.gallery3d.common.BlobCache; +import com.android.gallery3d.common.BlobCache.LookupRequest; +import com.android.gallery3d.common.Utils; +import com.android.gallery3d.data.BytesBufferPool.BytesBuffer; +import com.android.gallery3d.util.CacheManager; +import com.android.gallery3d.util.GalleryUtils; + +import java.io.IOException; +import java.nio.ByteBuffer; + +public class ImageCacheService { + @SuppressWarnings("unused") + private static final String TAG = "ImageCacheService"; + + private static final String IMAGE_CACHE_FILE = "imgcache"; + private static final int IMAGE_CACHE_MAX_ENTRIES = 5000; + private static final int IMAGE_CACHE_MAX_BYTES = 200 * 1024 * 1024; + private static final int IMAGE_CACHE_VERSION = 7; + + private BlobCache mCache; + + public ImageCacheService(Context context) { + mCache = CacheManager.getCache(context, IMAGE_CACHE_FILE, + IMAGE_CACHE_MAX_ENTRIES, IMAGE_CACHE_MAX_BYTES, + IMAGE_CACHE_VERSION); + } + + /** + * Gets the cached image data for the given <code>path</code>, + * <code>timeModified</code> and <code>type</code>. + * + * The image data will be stored in <code>buffer.data</code>, started from + * <code>buffer.offset</code> for <code>buffer.length</code> bytes. If the + * buffer.data is not big enough, a new byte array will be allocated and returned. + * + * @return true if the image data is found; false if not found. + */ + public boolean getImageData(Path path, long timeModified, int type, BytesBuffer buffer) { + byte[] key = makeKey(path, timeModified, type); + long cacheKey = Utils.crc64Long(key); + try { + LookupRequest request = new LookupRequest(); + request.key = cacheKey; + request.buffer = buffer.data; + synchronized (mCache) { + if (!mCache.lookup(request)) return false; + } + if (isSameKey(key, request.buffer)) { + buffer.data = request.buffer; + buffer.offset = key.length; + buffer.length = request.length - buffer.offset; + return true; + } + } catch (IOException ex) { + // ignore. + } + return false; + } + + public void putImageData(Path path, long timeModified, int type, byte[] value) { + byte[] key = makeKey(path, timeModified, type); + long cacheKey = Utils.crc64Long(key); + ByteBuffer buffer = ByteBuffer.allocate(key.length + value.length); + buffer.put(key); + buffer.put(value); + synchronized (mCache) { + try { + mCache.insert(cacheKey, buffer.array()); + } catch (IOException ex) { + // ignore. + } + } + } + + public void clearImageData(Path path, long timeModified, int type) { + byte[] key = makeKey(path, timeModified, type); + long cacheKey = Utils.crc64Long(key); + synchronized (mCache) { + try { + mCache.clearEntry(cacheKey); + } catch (IOException ex) { + // ignore. + } + } + } + + private static byte[] makeKey(Path path, long timeModified, int type) { + return GalleryUtils.getBytes(path.toString() + "+" + timeModified + "+" + type); + } + + private static boolean isSameKey(byte[] key, byte[] buffer) { + int n = key.length; + if (buffer.length < n) { + return false; + } + for (int i = 0; i < n; ++i) { + if (key[i] != buffer[i]) { + return false; + } + } + return true; + } +} |