Remove DrmSessionManager.acquirePlaceholderSession

In order to acquire a placeholder session, clients can call acquireSession
with a format with a null drmInitData.

PiperOrigin-RevId: 327220249

library/core/src/main/java/com/google/android/exoplayer2/drm/DefaultDrmSessionManager.java

@@ -409,7 +409,7 @@ public class DefaultDrmSessionManager implements DrmSessionManager {
   /**
    * Sets the mode, which determines the role of sessions acquired from the instance. This must be
    * called before {@link #acquireSession(Looper, DrmSessionEventListener.EventDispatcher, Format)}
-   * or {@link #acquirePlaceholderSession} is called.
+   * is called.
    *
    * <p>By default, the mode is {@link #MODE_PLAYBACK} and a streaming license is requested when
    * required.
@@ -469,34 +469,6 @@ public class DefaultDrmSessionManager implements DrmSessionManager {
 
   @Override
   @Nullable
-  public DrmSession acquirePlaceholderSession(Looper playbackLooper, int trackType) {
-    initPlaybackLooper(playbackLooper);
-    ExoMediaDrm exoMediaDrm = Assertions.checkNotNull(this.exoMediaDrm);
-    boolean avoidPlaceholderDrmSessions =
-        FrameworkMediaCrypto.class.equals(exoMediaDrm.getExoMediaCryptoType())
-            && FrameworkMediaCrypto.WORKAROUND_DEVICE_NEEDS_KEYS_TO_CONFIGURE_CODEC;
-    // Avoid attaching a session to sparse formats.
-    if (avoidPlaceholderDrmSessions
-        || Util.linearSearch(useDrmSessionsForClearContentTrackTypes, trackType) == C.INDEX_UNSET
-        || exoMediaDrm.getExoMediaCryptoType() == null) {
-      return null;
-    }
-    maybeCreateMediaDrmHandler(playbackLooper);
-    if (placeholderDrmSession == null) {
-      DefaultDrmSession placeholderDrmSession =
-          createAndAcquireSessionWithRetry(
-              /* schemeDatas= */ ImmutableList.of(),
-              /* isPlaceholderSession= */ true,
-              /* eventDispatcher= */ null);
-      sessions.add(placeholderDrmSession);
-      this.placeholderDrmSession = placeholderDrmSession;
-    } else {
-      placeholderDrmSession.acquire(/* eventDispatcher= */ null);
-    }
-    return placeholderDrmSession;
-  }
-
-  @Override
   public DrmSession acquireSession(
       Looper playbackLooper,
       @Nullable DrmSessionEventListener.EventDispatcher eventDispatcher,
@@ -504,6 +476,11 @@ public class DefaultDrmSessionManager implements DrmSessionManager {
     initPlaybackLooper(playbackLooper);
     maybeCreateMediaDrmHandler(playbackLooper);
 
+    if (format.drmInitData == null) {
+      // Content is not encrypted.
+      return maybeAcquirePlaceholderSession(MimeTypes.getTrackType(format.sampleMimeType));
+    }
+
     @Nullable List<SchemeData> schemeDatas = null;
     if (offlineLicenseKeySetId == null) {
       schemeDatas = getSchemeDatas(Assertions.checkNotNull(format.drmInitData), uuid, false);
@@ -565,6 +542,32 @@ public class DefaultDrmSessionManager implements DrmSessionManager {
 
   // Internal methods.
 
+  @Nullable
+  private DrmSession maybeAcquirePlaceholderSession(int trackType) {
+    ExoMediaDrm exoMediaDrm = Assertions.checkNotNull(this.exoMediaDrm);
+    boolean avoidPlaceholderDrmSessions =
+        FrameworkMediaCrypto.class.equals(exoMediaDrm.getExoMediaCryptoType())
+            && FrameworkMediaCrypto.WORKAROUND_DEVICE_NEEDS_KEYS_TO_CONFIGURE_CODEC;
+    // Avoid attaching a session to sparse formats.
+    if (avoidPlaceholderDrmSessions
+        || Util.linearSearch(useDrmSessionsForClearContentTrackTypes, trackType) == C.INDEX_UNSET
+        || exoMediaDrm.getExoMediaCryptoType() == null) {
+      return null;
+    }
+    if (placeholderDrmSession == null) {
+      DefaultDrmSession placeholderDrmSession =
+          createAndAcquireSessionWithRetry(
+              /* schemeDatas= */ ImmutableList.of(),
+              /* isPlaceholderSession= */ true,
+              /* eventDispatcher= */ null);
+      sessions.add(placeholderDrmSession);
+      this.placeholderDrmSession = placeholderDrmSession;
+    } else {
+      placeholderDrmSession.acquire(/* eventDispatcher= */ null);
+    }
+    return placeholderDrmSession;
+  }
+
   private boolean canAcquireSession(DrmInitData drmInitData) {
     if (offlineLicenseKeySetId != null) {
       // An offline license can be restored so a session can always be acquired.

library/core/src/main/java/com/google/android/exoplayer2/drm/DrmSessionManager.java

@@ -17,7 +17,6 @@ package com.google.android.exoplayer2.drm;
 
 import android.os.Looper;
 import androidx.annotation.Nullable;
-import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 
 /** Manages a DRM session. */
@@ -33,13 +32,19 @@ public interface DrmSessionManager {
       new DrmSessionManager() {
 
         @Override
+        @Nullable
         public DrmSession acquireSession(
             Looper playbackLooper,
             @Nullable DrmSessionEventListener.EventDispatcher eventDispatcher,
             Format format) {
-          return new ErrorStateDrmSession(
-              new DrmSession.DrmSessionException(
-                  new UnsupportedDrmException(UnsupportedDrmException.REASON_UNSUPPORTED_SCHEME)));
+          if (format.drmInitData == null) {
+            return null;
+          } else {
+            return new ErrorStateDrmSession(
+                new DrmSession.DrmSessionException(
+                    new UnsupportedDrmException(
+                        UnsupportedDrmException.REASON_UNSUPPORTED_SCHEME)));
+          }
         }
 
         @Override
@@ -65,38 +70,26 @@ public interface DrmSessionManager {
   }
 
   /**
-   * Returns a {@link DrmSession} that does not execute key requests, with an incremented reference
-   * count. When the caller no longer needs to use the instance, it must call {@link
-   * DrmSession#release(DrmSessionEventListener.EventDispatcher)} to decrement the reference count.
-   *
-   * <p>Placeholder {@link DrmSession DrmSessions} may be used to configure secure decoders for
-   * playback of clear content periods. This can reduce the cost of transitioning between clear and
-   * encrypted content periods.
-   *
-   * @param playbackLooper The looper associated with the media playback thread.
-   * @param trackType The type of the track to acquire a placeholder session for. Must be one of the
-   *     {@link C}{@code .TRACK_TYPE_*} constants.
-   * @return The placeholder DRM session, or null if this DRM session manager does not support
-   *     placeholder sessions.
-   */
-  @Nullable
-  default DrmSession acquirePlaceholderSession(Looper playbackLooper, int trackType) {
-    return null;
-  }
-
-  /**
    * Returns a {@link DrmSession} for the specified {@link Format}, with an incremented reference
-   * count. When the caller no longer needs to use the instance, it must call {@link
+   * count. May return null if the {@link Format#drmInitData} is null and the DRM session manager is
+   * not configured to attach a {@link DrmSession} to clear content. When the caller no longer needs
+   * to use a returned {@link DrmSession}, it must call {@link
    * DrmSession#release(DrmSessionEventListener.EventDispatcher)} to decrement the reference count.
    *
+   * <p>If the provided {@link Format} contains a null {@link Format#drmInitData}, the returned
+   * {@link DrmSession} (if not null) will be a placeholder session which does not execute key
+   * requests, and cannot be used to handle encrypted content. However, a placeholder session may be
+   * used to configure secure decoders for playback of clear content periods, which can reduce the
+   * cost of transitioning between clear and encrypted content.
+   *
    * @param playbackLooper The looper associated with the media playback thread.
    * @param eventDispatcher The {@link DrmSessionEventListener.EventDispatcher} used to distribute
    *     events, and passed on to {@link
    *     DrmSession#acquire(DrmSessionEventListener.EventDispatcher)}.
-   * @param format The {@link Format} for which to acquire a {@link DrmSession}. Must contain a
-   *     non-null {@link Format#drmInitData}.
-   * @return The DRM session.
+   * @param format The {@link Format} for which to acquire a {@link DrmSession}.
+   * @return The DRM session. May be null if the given {@link Format#drmInitData} is null.
    */
+  @Nullable
   DrmSession acquireSession(
       Looper playbackLooper,
       @Nullable DrmSessionEventListener.EventDispatcher eventDispatcher,
@@ -105,16 +98,16 @@ public interface DrmSessionManager {
   /**
    * Returns the {@link ExoMediaCrypto} type associated to sessions acquired for the given {@link
    * Format}. Returns the {@link UnsupportedMediaCrypto} type if this DRM session manager does not
-   * support any of the DRM schemes defined in the given {@link Format}. If the {@link Format}
-   * describes unencrypted content, returns an {@link ExoMediaCrypto} type if this DRM session
-   * manager would associate a {@link #acquirePlaceholderSession placeholder session} to the given
-   * {@link Format}, or null otherwise.
+   * support any of the DRM schemes defined in the given {@link Format}. Returns null if {@link
+   * Format#drmInitData} is null and {@link #acquireSession} would return null for the given {@link
+   * Format}.
    *
    * @param format The {@link Format} for which to return the {@link ExoMediaCrypto} type.
-   * @return The {@link ExoMediaCrypto} type associated to sessions acquired using the given
-   *     parameters, or the {@link UnsupportedMediaCrypto} type if the provided {@code drmInitData}
-   *     is not supported, or {@code null} if {@code drmInitData} is null and no DRM session will be
-   *     associated to the given {@code trackType}.
+   * @return The {@link ExoMediaCrypto} type associated to sessions acquired using the given {@link
+   *     Format}, or {@link UnsupportedMediaCrypto} if this DRM session manager does not support any
+   *     of the DRM schemes defined in the given {@link Format}. May be null if {@link
+   *     Format#drmInitData} is null and {@link #acquireSession} would return null for the given
+   *     {@link Format}.
    */
   @Nullable
   Class<? extends ExoMediaCrypto> getExoMediaCryptoType(Format format);

library/core/src/main/java/com/google/android/exoplayer2/drm/OfflineLicenseHelper.java

@@ -184,7 +184,8 @@ public final class OfflineLicenseHelper {
   /**
    * Downloads an offline license.
    *
-   * @param format The {@link Format} of the content whose license is to be downloaded.
+   * @param format The {@link Format} of the content whose license is to be downloaded. Must contain
+   *     a non-null {@link Format#drmInitData}.
    * @return The key set id for the downloaded license.
    * @throws DrmSessionException Thrown when a DRM session error occurs.
    */
@@ -278,13 +279,14 @@ public final class OfflineLicenseHelper {
 
   private DrmSession openBlockingKeyRequest(
       @Mode int licenseMode, @Nullable byte[] offlineLicenseKeySetId, Format format) {
+    Assertions.checkNotNull(format.drmInitData);
     drmSessionManager.setMode(licenseMode, offlineLicenseKeySetId);
     conditionVariable.close();
     DrmSession drmSession =
         drmSessionManager.acquireSession(handlerThread.getLooper(), eventDispatcher, format);
     // Block current thread until key loading is finished
     conditionVariable.block();
-    return drmSession;
+    return Assertions.checkNotNull(drmSession);
   }
 
 }

library/core/src/main/java/com/google/android/exoplayer2/source/SampleQueue.java

@@ -327,13 +327,7 @@ public class SampleQueue implements TrackOutput {
    * Attempts to read from the queue.
    *
    * <p>{@link Format Formats} read from this method may be associated to a {@link DrmSession}
-   * through {@link FormatHolder#drmSession}, which is populated in two scenarios:
-   *
-   * <ul>
-   *   <li>The {@link Format} has a non-null {@link Format#drmInitData}.
-   *   <li>The {@link DrmSessionManager} provides placeholder sessions for this queue's track type.
-   *       See {@link DrmSessionManager#acquirePlaceholderSession(Looper, int)}.
-   * </ul>
+   * through {@link FormatHolder#drmSession}.
    *
    * @param formatHolder A {@link FormatHolder} to populate in the case of reading a format.
    * @param buffer A {@link DecoderInputBuffer} to populate in the case of reading a sample or the
@@ -842,10 +836,7 @@ public class SampleQueue implements TrackOutput {
     // is being used for both DrmInitData.
     @Nullable DrmSession previousSession = currentDrmSession;
     currentDrmSession =
-        newDrmInitData != null
-            ? drmSessionManager.acquireSession(playbackLooper, drmEventDispatcher, newFormat)
-            : drmSessionManager.acquirePlaceholderSession(
-                playbackLooper, MimeTypes.getTrackType(newFormat.sampleMimeType));
+        drmSessionManager.acquireSession(playbackLooper, drmEventDispatcher, newFormat);
     outputFormatHolder.drmSession = currentDrmSession;
 
     if (previousSession != null) {

library/core/src/test/java/com/google/android/exoplayer2/source/SampleQueueTest.java

@@ -38,6 +38,7 @@ import com.google.android.exoplayer2.drm.DrmInitData;
 import com.google.android.exoplayer2.drm.DrmSession;
 import com.google.android.exoplayer2.drm.DrmSessionEventListener;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
+import com.google.android.exoplayer2.drm.ExoMediaCrypto;
 import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.testutil.TestUtil;
 import com.google.android.exoplayer2.upstream.Allocator;
@@ -54,7 +55,6 @@ import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.ArgumentMatchers;
 import org.mockito.Mockito;
 
 /** Test for {@link SampleQueue}. */
@@ -69,6 +69,8 @@ public final class SampleQueueTest {
   private static final Format FORMAT_SPLICED = buildFormat(/* id= */ "spliced");
   private static final Format FORMAT_ENCRYPTED =
       new Format.Builder().setId(/* id= */ "encrypted").setDrmInitData(new DrmInitData()).build();
+  private static final Format FORMAT_ENCRYPTED_WITH_EXO_MEDIA_CRYPTO_TYPE =
+      FORMAT_ENCRYPTED.copyWithExoMediaCryptoType(MockExoMediaCrypto.class);
   private static final byte[] DATA = TestUtil.buildTestData(ALLOCATION_SIZE * 10);
 
   /*
@@ -128,7 +130,7 @@ public final class SampleQueueTest {
       new TrackOutput.CryptoData(C.CRYPTO_MODE_AES_CTR, new byte[16], 0, 0);
 
   private Allocator allocator;
-  private DrmSessionManager mockDrmSessionManager;
+  private MockDrmSessionManager mockDrmSessionManager;
   private DrmSession mockDrmSession;
   private DrmSessionEventListener.EventDispatcher eventDispatcher;
   private SampleQueue sampleQueue;
@@ -138,11 +140,8 @@ public final class SampleQueueTest {
   @Before
   public void setUp() {
     allocator = new DefaultAllocator(false, ALLOCATION_SIZE);
-    mockDrmSessionManager = Mockito.mock(DrmSessionManager.class);
     mockDrmSession = Mockito.mock(DrmSession.class);
-    when(mockDrmSessionManager.acquireSession(
-            ArgumentMatchers.any(), ArgumentMatchers.any(), ArgumentMatchers.any()))
-        .thenReturn(mockDrmSession);
+    mockDrmSessionManager = new MockDrmSessionManager(mockDrmSession);
     eventDispatcher = new DrmSessionEventListener.EventDispatcher();
     sampleQueue =
         new SampleQueue(
@@ -399,7 +398,7 @@ public final class SampleQueueTest {
   @Test
   public void isReadyReturnsTrueForValidDrmSession() {
     writeTestDataWithEncryptedSections();
-    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED);
+    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED_WITH_EXO_MEDIA_CRYPTO_TYPE);
     assertThat(sampleQueue.isReady(/* loadingFinished= */ false)).isFalse();
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED_WITH_KEYS);
     assertThat(sampleQueue.isReady(/* loadingFinished= */ false)).isTrue();
@@ -424,7 +423,7 @@ public final class SampleQueueTest {
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED);
     writeTestDataWithEncryptedSections();
 
-    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED);
+    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED_WITH_EXO_MEDIA_CRYPTO_TYPE);
     assertReadNothing(/* formatRequired= */ false);
     assertThat(inputBuffer.waitingForKeys).isTrue();
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED_WITH_KEYS);
@@ -464,9 +463,7 @@ public final class SampleQueueTest {
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED_WITH_KEYS);
     DrmSession mockPlaceholderDrmSession = Mockito.mock(DrmSession.class);
     when(mockPlaceholderDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED_WITH_KEYS);
-    when(mockDrmSessionManager.acquirePlaceholderSession(
-            ArgumentMatchers.any(), ArgumentMatchers.anyInt()))
-        .thenReturn(mockPlaceholderDrmSession);
+    mockDrmSessionManager.mockPlaceholderDrmSession = mockPlaceholderDrmSession;
     writeTestDataWithEncryptedSections();
 
     int result =
@@ -497,9 +494,7 @@ public final class SampleQueueTest {
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED_WITH_KEYS);
     DrmSession mockPlaceholderDrmSession = Mockito.mock(DrmSession.class);
     when(mockPlaceholderDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED_WITH_KEYS);
-    when(mockDrmSessionManager.acquirePlaceholderSession(
-            ArgumentMatchers.any(), ArgumentMatchers.anyInt()))
-        .thenReturn(mockPlaceholderDrmSession);
+    mockDrmSessionManager.mockPlaceholderDrmSession = mockPlaceholderDrmSession;
 
     writeFormat(ENCRYPTED_SAMPLE_FORMATS[0]);
     byte[] sampleData = new byte[] {0, 1, 2};
@@ -540,7 +535,7 @@ public final class SampleQueueTest {
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED);
     writeTestDataWithEncryptedSections();
 
-    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED);
+    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED_WITH_EXO_MEDIA_CRYPTO_TYPE);
     assertReadNothing(/* formatRequired= */ false);
     sampleQueue.maybeThrowError();
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_ERROR);
@@ -569,7 +564,7 @@ public final class SampleQueueTest {
     when(mockDrmSession.getState()).thenReturn(DrmSession.STATE_OPENED);
     writeTestDataWithEncryptedSections();
 
-    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED);
+    assertReadFormat(/* formatRequired= */ false, FORMAT_ENCRYPTED_WITH_EXO_MEDIA_CRYPTO_TYPE);
     assertReadEncryptedSample(/* sampleIndex= */ 0);
   }
 
@@ -1497,4 +1492,33 @@ public final class SampleQueueTest {
   private static Format copyWithLabel(Format format, String label) {
     return format.buildUpon().setLabel(label).build();
   }
+
+  private static final class MockExoMediaCrypto implements ExoMediaCrypto {}
+
+  private static final class MockDrmSessionManager implements DrmSessionManager {
+
+    private final DrmSession mockDrmSession;
+    @Nullable private DrmSession mockPlaceholderDrmSession;
+
+    private MockDrmSessionManager(DrmSession mockDrmSession) {
+      this.mockDrmSession = mockDrmSession;
+    }
+
+    @Nullable
+    @Override
+    public DrmSession acquireSession(
+        Looper playbackLooper,
+        @Nullable DrmSessionEventListener.EventDispatcher eventDispatcher,
+        Format format) {
+      return format.drmInitData != null ? mockDrmSession : mockPlaceholderDrmSession;
+    }
+
+    @Nullable
+    @Override
+    public Class<? extends ExoMediaCrypto> getExoMediaCryptoType(Format format) {
+      return mockPlaceholderDrmSession != null || format.drmInitData != null
+          ? MockExoMediaCrypto.class
+          : null;
+    }
+  }
 }

testutils/src/main/java/com/google/android/exoplayer2/testutil/FakeSampleStream.java

@@ -30,7 +30,6 @@ import com.google.android.exoplayer2.drm.DrmSessionManager;
 import com.google.android.exoplayer2.source.MediaSourceEventListener;
 import com.google.android.exoplayer2.source.SampleStream;
 import com.google.android.exoplayer2.util.Assertions;
-import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.Util;
 import com.google.common.collect.Iterables;
 import java.io.IOException;
@@ -274,10 +273,7 @@ public class FakeSampleStream implements SampleStream {
     @Nullable DrmSession previousSession = currentDrmSession;
     Looper playbackLooper = Assertions.checkNotNull(Looper.myLooper());
     currentDrmSession =
-        newDrmInitData != null
-            ? drmSessionManager.acquireSession(playbackLooper, drmEventDispatcher, newFormat)
-            : drmSessionManager.acquirePlaceholderSession(
-                playbackLooper, MimeTypes.getTrackType(newFormat.sampleMimeType));
+        drmSessionManager.acquireSession(playbackLooper, drmEventDispatcher, newFormat);
     outputFormatHolder.drmSession = currentDrmSession;
 
     if (previousSession != null) {