Add NonNull annotations to metadata packages

Also remove MetadataRenderer and SpliceInfoDecoder from the
nullness blacklist

PiperOrigin-RevId: 283744417

library/core/src/main/java/com/google/android/exoplayer2/metadata/Metadata.java

@@ -22,7 +22,6 @@ import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.util.Util;
 import java.util.Arrays;
 import java.util.List;
-import org.checkerframework.checker.nullness.compatqual.NullableType;
 
 /**
  * A collection of metadata entries.
@@ -57,19 +56,15 @@ public final class Metadata implements Parcelable {
    * @param entries The metadata entries.
    */
   public Metadata(Entry... entries) {
-    this.entries = entries == null ? new Entry[0] : entries;
+    this.entries = entries;
   }
 
   /**
    * @param entries The metadata entries.
    */
   public Metadata(List<? extends Entry> entries) {
-    if (entries != null) {
     this.entries = new Entry[entries.size()];
     entries.toArray(this.entries);
-    } else {
-      this.entries = new Entry[0];
-    }
   }
 
   /* package */ Metadata(Parcel in) {
@@ -118,9 +113,10 @@ public final class Metadata implements Parcelable {
    * @return The metadata instance with the appended entries.
    */
   public Metadata copyWithAppendedEntries(Entry... entriesToAppend) {
-    @NullableType Entry[] merged = Arrays.copyOf(entries, entries.length + entriesToAppend.length);
+    if (entriesToAppend.length == 0) {
-    System.arraycopy(entriesToAppend, 0, merged, entries.length, entriesToAppend.length);
+      return this;
-    return new Metadata(Util.castNonNullTypeArray(merged));
+    }
+    return new Metadata(Util.nullSafeArrayConcatenation(entries, entriesToAppend));
   }
 
   @Override

library/core/src/main/java/com/google/android/exoplayer2/metadata/MetadataRenderer.java

@@ -15,6 +15,8 @@
  */
 package com.google.android.exoplayer2.metadata;
 
+import static com.google.android.exoplayer2.util.Util.castNonNull;
+
 import android.os.Handler;
 import android.os.Handler.Callback;
 import android.os.Looper;
@@ -22,7 +24,6 @@ import android.os.Message;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.BaseRenderer;
 import com.google.android.exoplayer2.C;
-import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.FormatHolder;
 import com.google.android.exoplayer2.util.Assertions;
@@ -30,6 +31,7 @@ import com.google.android.exoplayer2.util.Util;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
+import org.checkerframework.checker.nullness.compatqual.NullableType;
 
 /**
  * A renderer for metadata.
@@ -46,12 +48,12 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
   private final MetadataOutput output;
   @Nullable private final Handler outputHandler;
   private final MetadataInputBuffer buffer;
-  private final Metadata[] pendingMetadata;
+  private final @NullableType Metadata[] pendingMetadata;
   private final long[] pendingMetadataTimestamps;
 
   private int pendingMetadataIndex;
   private int pendingMetadataCount;
-  private MetadataDecoder decoder;
+  @Nullable private MetadataDecoder decoder;
   private boolean inputStreamEnded;
   private long subsampleOffsetUs;
 
@@ -98,7 +100,7 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
   }
 
   @Override
-  protected void onStreamChanged(Format[] formats, long offsetUs) throws ExoPlaybackException {
+  protected void onStreamChanged(Format[] formats, long offsetUs) {
     decoder = decoderFactory.createDecoder(formats[0]);
   }
 
@@ -109,7 +111,7 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
   }
 
   @Override
-  public void render(long positionUs, long elapsedRealtimeUs) throws ExoPlaybackException {
+  public void render(long positionUs, long elapsedRealtimeUs) {
     if (!inputStreamEnded && pendingMetadataCount < MAX_PENDING_METADATA_COUNT) {
       buffer.clear();
       FormatHolder formatHolder = getFormatHolder();
@@ -124,7 +126,7 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
         } else {
           buffer.subsampleOffsetUs = subsampleOffsetUs;
           buffer.flip();
-          Metadata metadata = decoder.decode(buffer);
+          @Nullable Metadata metadata = castNonNull(decoder).decode(buffer);
           if (metadata != null) {
             List<Metadata.Entry> entries = new ArrayList<>(metadata.length());
             decodeWrappedMetadata(metadata, entries);
@@ -139,12 +141,13 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
           }
         }
       } else if (result == C.RESULT_FORMAT_READ) {
-        subsampleOffsetUs = formatHolder.format.subsampleOffsetUs;
+        subsampleOffsetUs = Assertions.checkNotNull(formatHolder.format).subsampleOffsetUs;
       }
     }
 
     if (pendingMetadataCount > 0 && pendingMetadataTimestamps[pendingMetadataIndex] <= positionUs) {
-      invokeRenderer(pendingMetadata[pendingMetadataIndex]);
+      Metadata metadata = castNonNull(pendingMetadata[pendingMetadataIndex]);
+      invokeRenderer(metadata);
       pendingMetadata[pendingMetadataIndex] = null;
       pendingMetadataIndex = (pendingMetadataIndex + 1) % MAX_PENDING_METADATA_COUNT;
       pendingMetadataCount--;
@@ -158,7 +161,7 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
    */
   private void decodeWrappedMetadata(Metadata metadata, List<Metadata.Entry> decodedEntries) {
     for (int i = 0; i < metadata.length(); i++) {
-      Format wrappedMetadataFormat = metadata.get(i).getWrappedMetadataFormat();
+      @Nullable Format wrappedMetadataFormat = metadata.get(i).getWrappedMetadataFormat();
       if (wrappedMetadataFormat != null && decoderFactory.supportsFormat(wrappedMetadataFormat)) {
         MetadataDecoder wrappedMetadataDecoder =
             decoderFactory.createDecoder(wrappedMetadataFormat);
@@ -167,7 +170,7 @@ public final class MetadataRenderer extends BaseRenderer implements Callback {
             Assertions.checkNotNull(metadata.get(i).getWrappedMetadataBytes());
         buffer.clear();
         buffer.ensureSpaceForWrite(wrappedMetadataBytes.length);
-        buffer.data.put(wrappedMetadataBytes);
+        castNonNull(buffer.data).put(wrappedMetadataBytes);
         buffer.flip();
         @Nullable Metadata innerMetadata = wrappedMetadataDecoder.decode(buffer);
         if (innerMetadata != null) {

library/core/src/main/java/com/google/android/exoplayer2/metadata/emsg/package-info.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+@NonNullApi
+package com.google.android.exoplayer2.metadata.emsg;
+
+import com.google.android.exoplayer2.util.NonNullApi;

library/core/src/main/java/com/google/android/exoplayer2/metadata/flac/package-info.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+@NonNullApi
+package com.google.android.exoplayer2.metadata.flac;
+
+import com.google.android.exoplayer2.util.NonNullApi;

library/core/src/main/java/com/google/android/exoplayer2/metadata/icy/IcyDecoder.java

@@ -15,6 +15,7 @@
  */
 package com.google.android.exoplayer2.metadata.icy;
 
+import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 import com.google.android.exoplayer2.metadata.Metadata;
 import com.google.android.exoplayer2.metadata.MetadataDecoder;
@@ -28,8 +29,6 @@ import java.util.regex.Pattern;
 /** Decodes ICY stream information. */
 public final class IcyDecoder implements MetadataDecoder {
 
-  private static final String TAG = "IcyDecoder";
-
   private static final Pattern METADATA_ELEMENT = Pattern.compile("(.+?)='(.*?)';", Pattern.DOTALL);
   private static final String STREAM_KEY_NAME = "streamtitle";
   private static final String STREAM_KEY_URL = "streamurl";
@@ -45,8 +44,8 @@ public final class IcyDecoder implements MetadataDecoder {
 
   @VisibleForTesting
   /* package */ Metadata decode(String metadata) {
-    String name = null;
+    @Nullable String name = null;
-    String url = null;
+    @Nullable String url = null;
     int index = 0;
     Matcher matcher = METADATA_ELEMENT.matcher(metadata);
     while (matcher.find(index)) {

library/core/src/main/java/com/google/android/exoplayer2/metadata/icy/package-info.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+@NonNullApi
+package com.google.android.exoplayer2.metadata.icy;
+
+import com.google.android.exoplayer2.util.NonNullApi;

library/core/src/main/java/com/google/android/exoplayer2/metadata/id3/ApicFrame.java

@@ -47,7 +47,7 @@ public final class ApicFrame extends Id3Frame {
   /* package */ ApicFrame(Parcel in) {
     super(ID);
     mimeType = castNonNull(in.readString());
-    description = castNonNull(in.readString());
+    description = in.readString();
     pictureType = in.readInt();
     pictureData = castNonNull(in.createByteArray());
   }

library/core/src/main/java/com/google/android/exoplayer2/metadata/id3/Id3Decoder.java

@@ -155,7 +155,8 @@ public final class Id3Decoder implements MetadataDecoder {
    * @param data A {@link ParsableByteArray} from which the header should be read.
    * @return The parsed header, or null if the ID3 tag is unsupported.
    */
-  private static @Nullable Id3Header decodeHeader(ParsableByteArray data) {
+  @Nullable
+  private static Id3Header decodeHeader(ParsableByteArray data) {
     if (data.bytesLeft() < ID3_HEADER_LENGTH) {
       Log.w(TAG, "Data too short to be an ID3 tag");
       return null;
@@ -269,7 +270,8 @@ public final class Id3Decoder implements MetadataDecoder {
     }
   }
 
-  private static @Nullable Id3Frame decodeFrame(
+  @Nullable
+  private static Id3Frame decodeFrame(
       int majorVersion,
       ParsableByteArray id3Data,
       boolean unsignedIntFrameSizeHack,
@@ -404,8 +406,9 @@ public final class Id3Decoder implements MetadataDecoder {
     }
   }
 
-  private static @Nullable TextInformationFrame decodeTxxxFrame(
+  @Nullable
-      ParsableByteArray id3Data, int frameSize) throws UnsupportedEncodingException {
+  private static TextInformationFrame decodeTxxxFrame(ParsableByteArray id3Data, int frameSize)
+      throws UnsupportedEncodingException {
     if (frameSize < 1) {
       // Frame is malformed.
       return null;
@@ -427,7 +430,8 @@ public final class Id3Decoder implements MetadataDecoder {
     return new TextInformationFrame("TXXX", description, value);
   }
 
-  private static @Nullable TextInformationFrame decodeTextInformationFrame(
+  @Nullable
+  private static TextInformationFrame decodeTextInformationFrame(
       ParsableByteArray id3Data, int frameSize, String id) throws UnsupportedEncodingException {
     if (frameSize < 1) {
       // Frame is malformed.
@@ -446,7 +450,8 @@ public final class Id3Decoder implements MetadataDecoder {
     return new TextInformationFrame(id, null, value);
   }
 
-  private static @Nullable UrlLinkFrame decodeWxxxFrame(ParsableByteArray id3Data, int frameSize)
+  @Nullable
+  private static UrlLinkFrame decodeWxxxFrame(ParsableByteArray id3Data, int frameSize)
       throws UnsupportedEncodingException {
     if (frameSize < 1) {
       // Frame is malformed.
@@ -557,7 +562,8 @@ public final class Id3Decoder implements MetadataDecoder {
     return new ApicFrame(mimeType, description, pictureType, pictureData);
   }
 
-  private static @Nullable CommentFrame decodeCommentFrame(ParsableByteArray id3Data, int frameSize)
+  @Nullable
+  private static CommentFrame decodeCommentFrame(ParsableByteArray id3Data, int frameSize)
       throws UnsupportedEncodingException {
     if (frameSize < 4) {
       // Frame is malformed.

library/core/src/main/java/com/google/android/exoplayer2/metadata/id3/package-info.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+@NonNullApi
+package com.google.android.exoplayer2.metadata.id3;
+
+import com.google.android.exoplayer2.util.NonNullApi;

library/core/src/main/java/com/google/android/exoplayer2/metadata/package-info.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+@NonNullApi
+package com.google.android.exoplayer2.metadata;
+
+import com.google.android.exoplayer2.util.NonNullApi;

library/core/src/main/java/com/google/android/exoplayer2/metadata/scte35/SpliceInfoDecoder.java

@@ -15,13 +15,16 @@
  */
 package com.google.android.exoplayer2.metadata.scte35;
 
+import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.metadata.Metadata;
 import com.google.android.exoplayer2.metadata.MetadataDecoder;
 import com.google.android.exoplayer2.metadata.MetadataInputBuffer;
+import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.ParsableBitArray;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 import com.google.android.exoplayer2.util.TimestampAdjuster;
 import java.nio.ByteBuffer;
+import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
 /**
  * Decodes splice info sections and produces splice commands.
@@ -37,7 +40,7 @@ public final class SpliceInfoDecoder implements MetadataDecoder {
   private final ParsableByteArray sectionData;
   private final ParsableBitArray sectionHeader;
 
-  private TimestampAdjuster timestampAdjuster;
+  @MonotonicNonNull private TimestampAdjuster timestampAdjuster;
 
   public SpliceInfoDecoder() {
     sectionData = new ParsableByteArray();
@@ -47,6 +50,8 @@ public final class SpliceInfoDecoder implements MetadataDecoder {
   @SuppressWarnings("ByteBufferBackingArray")
   @Override
   public Metadata decode(MetadataInputBuffer inputBuffer) {
+    ByteBuffer buffer = Assertions.checkNotNull(inputBuffer.data);
+
     // Internal timestamps adjustment.
     if (timestampAdjuster == null
         || inputBuffer.subsampleOffsetUs != timestampAdjuster.getTimestampOffsetUs()) {
@@ -54,7 +59,6 @@ public final class SpliceInfoDecoder implements MetadataDecoder {
       timestampAdjuster.adjustSampleTimestamp(inputBuffer.timeUs - inputBuffer.subsampleOffsetUs);
     }
 
-    ByteBuffer buffer = inputBuffer.data;
     byte[] data = buffer.array();
     int size = buffer.limit();
     sectionData.reset(data, size);
@@ -68,7 +72,7 @@ public final class SpliceInfoDecoder implements MetadataDecoder {
     sectionHeader.skipBits(20);
     int spliceCommandLength = sectionHeader.readBits(12);
     int spliceCommandType = sectionHeader.readBits(8);
-    SpliceCommand command = null;
+    @Nullable SpliceCommand command = null;
     // Go to the start of the command by skipping all fields up to command_type.
     sectionData.skipBytes(14);
     switch (spliceCommandType) {

library/core/src/main/java/com/google/android/exoplayer2/metadata/scte35/package-info.java

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+@NonNullApi
+package com.google.android.exoplayer2.metadata.scte35;
+
+import com.google.android.exoplayer2.util.NonNullApi;