Initial checkin of AOSP Messaging app.

b/23110861

Change-Id: I9aa980d7569247d6b2ca78f5dcb4502e1eaadb8a

src/com/android/messaging/datamodel/media/MediaRequest.java

@@ -0,0 +1,70 @@
+/*
+ * 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 java.util.List;
+
+/**
+ * Keeps track of a media loading request. MediaResourceManager uses this interface to load, encode,
+ * decode, and cache different types of media resource.
+ *
+ * This interface defines a media request class that's threading-model-blind. Wrapper classes
+ * (such as {@link AsyncMediaRequestWrapper} wraps around any base media request to offer async
+ * extensions).
+ */
+public interface MediaRequest<T extends RefCountedMediaResource> {
+    public static final int REQUEST_ENCODE_MEDIA = 1;
+    public static final int REQUEST_DECODE_MEDIA = 2;
+    public static final int REQUEST_LOAD_MEDIA = 3;
+
+    /**
+     * Returns a unique key used for storing and looking up the MediaRequest.
+     */
+    String getKey();
+
+    /**
+     * This method performs the heavy-lifting work of synchronously loading the media bytes for
+     * this MediaRequest on a single threaded executor.
+     * @param chainedTask subsequent tasks to be performed after this request is complete. For
+     * example, an image request may need to compress the image resource before putting it in the
+     * cache
+     */
+    T loadMediaBlocking(List<MediaRequest<T>> chainedTask) throws Exception;
+
+    /**
+     * Returns the media cache where this MediaRequest wants to store the loaded
+     * media resource.
+     */
+    MediaCache<T> getMediaCache();
+
+    /**
+     * Returns the id of the cache where this MediaRequest wants to store the loaded
+     * media resource.
+     */
+    int getCacheId();
+
+    /**
+     * Returns the request type of this media request, i.e. one of {@link #REQUEST_ENCODE_MEDIA},
+     * {@link #REQUEST_DECODE_MEDIA}, or {@link #REQUEST_LOAD_MEDIA}. The default is
+     * {@link #REQUEST_LOAD_MEDIA}
+     */
+    int getRequestType();
+
+    /**
+     * Returns the descriptor defining the request.
+     */
+    MediaRequestDescriptor<T> getDescriptor();
+}