Use FlacLibrary.isAvailable in FlacExtractor selection

PiperOrigin-RevId: 288667790

extensions/flac/src/test/java/com/google/android/exoplayer2/ext/flac/DefaultExtractorsFactoryTest.java

-/*
- * Copyright (C) 2016 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.google.android.exoplayer2.ext.flac;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import androidx.test.ext.junit.runners.AndroidJUnit4;
-import com.google.android.exoplayer2.extractor.DefaultExtractorsFactory;
-import com.google.android.exoplayer2.extractor.Extractor;
-import com.google.android.exoplayer2.extractor.amr.AmrExtractor;
-import com.google.android.exoplayer2.extractor.flv.FlvExtractor;
-import com.google.android.exoplayer2.extractor.mkv.MatroskaExtractor;
-import com.google.android.exoplayer2.extractor.mp3.Mp3Extractor;
-import com.google.android.exoplayer2.extractor.mp4.FragmentedMp4Extractor;
-import com.google.android.exoplayer2.extractor.mp4.Mp4Extractor;
-import com.google.android.exoplayer2.extractor.ogg.OggExtractor;
-import com.google.android.exoplayer2.extractor.ts.Ac3Extractor;
-import com.google.android.exoplayer2.extractor.ts.Ac4Extractor;
-import com.google.android.exoplayer2.extractor.ts.AdtsExtractor;
-import com.google.android.exoplayer2.extractor.ts.PsExtractor;
-import com.google.android.exoplayer2.extractor.ts.TsExtractor;
-import com.google.android.exoplayer2.extractor.wav.WavExtractor;
-import java.util.ArrayList;
-import java.util.List;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-
-/** Unit test for {@link DefaultExtractorsFactory}. */
-@RunWith(AndroidJUnit4.class)
-public final class DefaultExtractorsFactoryTest {
-
-  @Test
-  public void testCreateExtractors_returnExpectedClasses() {
-    DefaultExtractorsFactory defaultExtractorsFactory = new DefaultExtractorsFactory();
-
-    Extractor[] extractors = defaultExtractorsFactory.createExtractors();
-    List<Class<?>> listCreatedExtractorClasses = new ArrayList<>();
-    for (Extractor extractor : extractors) {
-      listCreatedExtractorClasses.add(extractor.getClass());
-    }
-
-    Class<?>[] expectedExtractorClassses =
-        new Class<?>[] {
-          MatroskaExtractor.class,
-          FragmentedMp4Extractor.class,
-          Mp4Extractor.class,
-          Mp3Extractor.class,
-          AdtsExtractor.class,
-          Ac3Extractor.class,
-          Ac4Extractor.class,
-          TsExtractor.class,
-          FlvExtractor.class,
-          OggExtractor.class,
-          PsExtractor.class,
-          WavExtractor.class,
-          AmrExtractor.class,
-          FlacExtractor.class
-        };
-
-    assertThat(listCreatedExtractorClasses).containsNoDuplicates();
-    assertThat(listCreatedExtractorClasses).containsExactlyElementsIn(expectedExtractorClassses);
-  }
-}

library/core/proguard-rules.txt

@@ -5,6 +5,12 @@
   public static android.net.Uri buildRawResourceUri(int);
 }
 
+# Methods accessed via reflection in DefaultExtractorsFactory
+-dontnote com.google.android.exoplayer2.ext.flac.FlacLibrary
+-keepclassmembers class com.google.android.exoplayer2.ext.flac.FlacLibrary {
+  public static boolean isAvailable();
+}
+
 # Some members of this class are being accessed from native methods. Keep them unobfuscated.
 -keep class com.google.android.exoplayer2.video.VideoDecoderOutputBuffer {
   *;

library/core/src/main/java/com/google/android/exoplayer2/extractor/DefaultExtractorsFactory.java

@@ -62,10 +62,18 @@ public final class DefaultExtractorsFactory implements ExtractorsFactory {
     Constructor<? extends Extractor> flacExtensionExtractorConstructor = null;
     try {
       // LINT.IfChange
-      flacExtensionExtractorConstructor =
-          Class.forName("com.google.android.exoplayer2.ext.flac.FlacExtractor")
-              .asSubclass(Extractor.class)
-              .getConstructor();
+      @SuppressWarnings("nullness:argument.type.incompatible")
+      boolean isFlacNativeLibraryAvailable =
+          Boolean.TRUE.equals(
+              Class.forName("com.google.android.exoplayer2.ext.flac.FlacLibrary")
+                  .getMethod("isAvailable")
+                  .invoke(/* obj= */ null));
+      if (isFlacNativeLibraryAvailable) {
+        flacExtensionExtractorConstructor =
+            Class.forName("com.google.android.exoplayer2.ext.flac.FlacExtractor")
+                .asSubclass(Extractor.class)
+                .getConstructor();
+      }
       // LINT.ThenChange(../../../../../../../../proguard-rules.txt)
     } catch (ClassNotFoundException e) {
       // Expected if the app was built without the FLAC extension.