1 files changed, 162 insertions, 0 deletions
diff --git a/src/com/android/messaging/datamodel/media/EncodedImageResource.java b/src/com/android/messaging/datamodel/media/EncodedImageResource.java
new file mode 100644
index 0000000..0bc94e5
--- /dev/null
+++ b/src/com/android/messaging/datamodel/media/EncodedImageResource.java
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2015 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.messaging.datamodel.media;
+
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.graphics.drawable.Drawable;
+
+import com.android.messaging.util.Assert;
+import com.android.messaging.util.Assert.DoesNotRunOnMainThread;
+
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * A cache-facing image resource that's much more compact than the raw Bitmap objects stored in
+ * {@link com.android.messaging.datamodel.media.DecodedImageResource}.
+ *
+ * This resource is created from a regular Bitmap-based ImageResource before being pushed to
+ * {@link com.android.messaging.datamodel.media.MediaCache}, if the image request
+ * allows for resource encoding/compression.
+ *
+ * During resource retrieval on cache hit,
+ * {@link #getMediaDecodingRequest(MediaRequest)} is invoked to create a async
+ * decode task, which decodes the compressed byte array back to a regular image resource to
+ * be consumed by the UI.
+ */
+public class EncodedImageResource extends ImageResource {
+    private final byte[] mImageBytes;
+
+    public EncodedImageResource(String key, byte[] imageBytes, int orientation) {
+        super(key, orientation);
+        mImageBytes = imageBytes;
+    }
+
+    @Override
+    @DoesNotRunOnMainThread
+    public Bitmap getBitmap() {
+        acquireLock();
+        try {
+            // This should only be called during the decode request.
+            Assert.isNotMainThread();
+            return BitmapFactory.decodeByteArray(mImageBytes, 0, mImageBytes.length);
+        } finally {
+            releaseLock();
+        }
+    }
+
+    @Override
+    public byte[] getBytes() {
+        acquireLock();
+        try {
+            return Arrays.copyOf(mImageBytes, mImageBytes.length);
+        } finally {
+            releaseLock();
+        }
+    }
+
+    @Override
+    public Bitmap reuseBitmap() {
+        return null;
+    }
+
+    @Override
+    public boolean supportsBitmapReuse() {
+        return false;
+    }
+
+    @Override
+    public int getMediaSize() {
+        return mImageBytes.length;
+    }
+
+    @Override
+    protected void close() {
+    }
+
+    @Override
+    public Drawable getDrawable(Resources resources) {
+        return null;
+    }
+
+    @Override
+    boolean isEncoded() {
+        return true;
+    }
+
+    @Override
+    MediaRequest<? extends RefCountedMediaResource> getMediaDecodingRequest(
+            final MediaRequest<? extends RefCountedMediaResource> originalRequest) {
+        Assert.isTrue(isEncoded());
+        return new DecodeImageRequest();
+    }
+
+    /**
+     * A MediaRequest that decodes the encoded image resource. This class is chained to the
+     * original media request that requested the image, so it inherits the listener and
+     * properties such as binding.
+     */
+    private class DecodeImageRequest implements MediaRequest<ImageResource> {
+        public DecodeImageRequest() {
+            // Hold a ref onto the encoded resource before the request finishes.
+            addRef();
+        }
+
+        @Override
+        public String getKey() {
+            return EncodedImageResource.this.getKey();
+        }
+
+        @Override
+        @DoesNotRunOnMainThread
+        public ImageResource loadMediaBlocking(List<MediaRequest<ImageResource>> chainedTask)
+                throws Exception {
+            Assert.isNotMainThread();
+            acquireLock();
+            try {
+                final Bitmap decodedBitmap = BitmapFactory.decodeByteArray(mImageBytes, 0,
+                        mImageBytes.length);
+                return new DecodedImageResource(getKey(), decodedBitmap, getOrientation());
+            } finally {
+                releaseLock();
+                release();
+            }
+        }
+
+        @Override
+        public MediaCache<ImageResource> getMediaCache() {
+            // Decoded resource is non-cachable, it's for UI consumption only (for now at least)
+            return null;
+        }
+
+        @Override
+        public int getCacheId() {
+            return 0;
+        }
+
+        @Override
+        public int getRequestType() {
+            return REQUEST_DECODE_MEDIA;
+        }
+
+        @Override
+        public MediaRequestDescriptor<ImageResource> getDescriptor() {
+            return null;
+        }
+    }
+}