SimpleBitmapLoader.java
/*
* Copyright 2022 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 androidx.media3.session;
import static androidx.media3.common.util.Assertions.checkStateNotNull;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import androidx.annotation.Nullable;
import androidx.media3.common.util.UnstableApi;
import com.google.common.base.Supplier;
import com.google.common.base.Suppliers;
import com.google.common.io.ByteStreams;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.MoreExecutors;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLConnection;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
/**
* A simple bitmap loader that delegates all tasks to an executor and supports fetching images from
* HTTP/HTTPS endpoints.
*
* <p>Loading tasks are delegated to an {@link ExecutorService} (or {@link
* ListeningExecutorService}) defined during construction. If no executor service is defined, all
* tasks are delegated to a single-thread executor service that is shared between instances of this
* class.
*
* <p>The supported URI scheme is only HTTP/HTTPS and this class reads a resource only when the
* endpoint responds with an {@code HTTP 200} after sending the HTTP request.
*/
@UnstableApi
public final class SimpleBitmapLoader implements BitmapLoader {
private static final Supplier<ListeningExecutorService> DEFAULT_EXECUTOR_SERVICE =
Suppliers.memoize(
() -> MoreExecutors.listeningDecorator(Executors.newSingleThreadExecutor()));
private final ListeningExecutorService executorService;
/**
* Creates an instance that delegates all load tasks to a single-thread executor service shared
* between instances.
*/
public SimpleBitmapLoader() {
this(checkStateNotNull(DEFAULT_EXECUTOR_SERVICE.get()));
}
/** Creates an instance that delegates loading tasks to the {@code executorService}. */
public SimpleBitmapLoader(ExecutorService executorService) {
this.executorService = MoreExecutors.listeningDecorator(executorService);
}
@Override
public ListenableFuture<Bitmap> decodeBitmap(byte[] data) {
return executorService.submit(() -> decode(data));
}
@Override
public ListenableFuture<Bitmap> loadBitmap(Uri uri) {
return executorService.submit(() -> load(uri));
}
private static Bitmap decode(byte[] data) {
@Nullable Bitmap bitmap = BitmapFactory.decodeByteArray(data, /* offset= */ 0, data.length);
if (bitmap == null) {
throw new IllegalArgumentException("Could not decode bitmap");
}
return bitmap;
}
private static Bitmap load(Uri uri) throws IOException {
URLConnection connection = new URL(uri.toString()).openConnection();
if (!(connection instanceof HttpURLConnection)) {
throw new UnsupportedOperationException("Unsupported scheme: " + uri.getScheme());
}
HttpURLConnection httpConnection = (HttpURLConnection) connection;
httpConnection.connect();
int responseCode = httpConnection.getResponseCode();
if (responseCode != HttpURLConnection.HTTP_OK) {
throw new IOException("Invalid response status code: " + responseCode);
}
try (InputStream inputStream = httpConnection.getInputStream()) {
return decode(ByteStreams.toByteArray(inputStream));
}
}
}