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;
+    }
+}