Clean up some extrator SeekMap implementations

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=177173618

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

@@ -32,7 +32,7 @@ import java.lang.annotation.RetentionPolicy;
 /**
  * Extracts data from the FLV container format.
  */
-public final class FlvExtractor implements Extractor, SeekMap {
+public final class FlvExtractor implements Extractor {
 
   /**
    * Factory for {@link FlvExtractor} instances.
@@ -70,32 +70,28 @@ public final class FlvExtractor implements Extractor, SeekMap {
   // FLV container identifier.
   private static final int FLV_TAG = Util.getIntegerCodeForString("FLV");
 
-  // Temporary buffers.
   private final ParsableByteArray scratch;
   private final ParsableByteArray headerBuffer;
   private final ParsableByteArray tagHeaderBuffer;
   private final ParsableByteArray tagData;
+  private final ScriptTagPayloadReader metadataReader;
 
-  // Extractor outputs.
   private ExtractorOutput extractorOutput;
-
-  // State variables.
   private @States int state;
   private int bytesToNextTagHeader;
   private int tagType;
   private int tagDataSize;
   private long tagTimestampUs;
-
-  // Tags readers.
+  private boolean outputSeekMap;
   private AudioTagPayloadReader audioReader;
   private VideoTagPayloadReader videoReader;
-  private ScriptTagPayloadReader metadataReader;
 
   public FlvExtractor() {
     scratch = new ParsableByteArray(4);
     headerBuffer = new ParsableByteArray(FLV_HEADER_SIZE);
     tagHeaderBuffer = new ParsableByteArray(FLV_TAG_HEADER_SIZE);
     tagData = new ParsableByteArray();
+    metadataReader = new ScriptTagPayloadReader();
     state = STATE_READING_FLV_HEADER;
   }
 
@@ -203,11 +199,7 @@ public final class FlvExtractor implements Extractor, SeekMap {
       videoReader = new VideoTagPayloadReader(
           extractorOutput.track(TAG_TYPE_VIDEO, C.TRACK_TYPE_VIDEO));
     }
-    if (metadataReader == null) {
-      metadataReader = new ScriptTagPayloadReader(null);
-    }
     extractorOutput.endTracks();
-    extractorOutput.seekMap(this);
 
     // We need to skip any additional content in the FLV header, plus the 4 byte previous tag size.
     bytesToNextTagHeader = headerBuffer.readInt() - FLV_HEADER_SIZE + 4;
@@ -263,11 +255,18 @@ public final class FlvExtractor implements Extractor, SeekMap {
   private boolean readTagData(ExtractorInput input) throws IOException, InterruptedException {
     boolean wasConsumed = true;
     if (tagType == TAG_TYPE_AUDIO && audioReader != null) {
+      ensureOutputSeekMap();
       audioReader.consume(prepareTagData(input), tagTimestampUs);
     } else if (tagType == TAG_TYPE_VIDEO && videoReader != null) {
+      ensureOutputSeekMap();
       videoReader.consume(prepareTagData(input), tagTimestampUs);
-    } else if (tagType == TAG_TYPE_SCRIPT_DATA && metadataReader != null) {
+    } else if (tagType == TAG_TYPE_SCRIPT_DATA && !outputSeekMap) {
       metadataReader.consume(prepareTagData(input), tagTimestampUs);
+      long durationUs = metadataReader.getDurationUs();
+      if (durationUs != C.TIME_UNSET) {
+        extractorOutput.seekMap(new SeekMap.Unseekable(durationUs));
+        outputSeekMap = true;
+      }
     } else {
       input.skipFully(tagDataSize);
       wasConsumed = false;
@@ -289,21 +288,11 @@ public final class FlvExtractor implements Extractor, SeekMap {
     return tagData;
   }
 
-  // SeekMap implementation.
-
-  @Override
-  public boolean isSeekable() {
-    return false;
+  private void ensureOutputSeekMap() {
+    if (!outputSeekMap) {
+      extractorOutput.seekMap(new SeekMap.Unseekable(C.TIME_UNSET));
+      outputSeekMap = true;
     }
-
-  @Override
-  public long getDurationUs() {
-    return metadataReader.getDurationUs();
-  }
-
-  @Override
-  public long getPosition(long timeUs) {
-    return 0;
   }
 
 }

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

@@ -17,7 +17,6 @@ package com.google.android.exoplayer2.extractor.flv;
 
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.ParserException;
-import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.util.ParsableByteArray;
 import java.util.ArrayList;
 import java.util.Date;
@@ -44,11 +43,8 @@ import java.util.Map;
 
   private long durationUs;
 
-  /**
-   * @param output A {@link TrackOutput} to which samples should be written.
-   */
-  public ScriptTagPayloadReader(TrackOutput output) {
-    super(output);
+  public ScriptTagPayloadReader() {
+    super(null);
     durationUs = C.TIME_UNSET;
   }
 

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

@@ -23,7 +23,6 @@ import com.google.android.exoplayer2.extractor.ExtractorInput;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
 import com.google.android.exoplayer2.extractor.ExtractorsFactory;
 import com.google.android.exoplayer2.extractor.PositionHolder;
-import com.google.android.exoplayer2.extractor.SeekMap;
 import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.util.MimeTypes;
 import java.io.IOException;
@@ -31,7 +30,7 @@ import java.io.IOException;
 /**
  * Extracts data from WAV byte streams.
  */
-public final class WavExtractor implements Extractor, SeekMap {
+public final class WavExtractor implements Extractor {
 
   /**
    * Factory for {@link WavExtractor} instances.
@@ -95,7 +94,7 @@ public final class WavExtractor implements Extractor, SeekMap {
 
     if (!wavHeader.hasDataBounds()) {
       WavHeaderReader.skipToData(input, wavHeader);
-      extractorOutput.seekMap(this);
+      extractorOutput.seekMap(wavHeader);
     }
 
     int bytesAppended = trackOutput.sampleData(input, MAX_INPUT_SIZE - pendingBytes, true);
@@ -115,20 +114,4 @@ public final class WavExtractor implements Extractor, SeekMap {
     return bytesAppended == RESULT_END_OF_INPUT ? RESULT_END_OF_INPUT : RESULT_CONTINUE;
   }
 
-  // SeekMap implementation.
-
-  @Override
-  public long getDurationUs() {
-    return wavHeader.getDurationUs();
-  }
-
-  @Override
-  public boolean isSeekable() {
-    return true;
-  }
-
-  @Override
-  public long getPosition(long timeUs) {
-    return wavHeader.getPosition(timeUs);
-  }
 }

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

@@ -16,9 +16,10 @@
 package com.google.android.exoplayer2.extractor.wav;
 
 import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.extractor.SeekMap;
 
 /** Header for a WAV file. */
-/*package*/ final class WavHeader {
+/* package */ final class WavHeader implements SeekMap {
 
   /** Number of audio chanels. */
   private final int numChannels;
@@ -49,12 +50,56 @@ import com.google.android.exoplayer2.C;
     this.encoding = encoding;
   }
 
-  /** Returns the duration in microseconds of this WAV. */
+  // Setting bounds.
+
+  /**
+   * Sets the data start position and size in bytes of sample data in this WAV.
+   *
+   * @param dataStartPosition The data start position in bytes.
+   * @param dataSize The data size in bytes.
+   */
+  public void setDataBounds(long dataStartPosition, long dataSize) {
+    this.dataStartPosition = dataStartPosition;
+    this.dataSize = dataSize;
+  }
+
+  /** Returns whether the data start position and size have been set. */
+  public boolean hasDataBounds() {
+    return dataStartPosition != 0 && dataSize != 0;
+  }
+
+  // SeekMap implementation.
+
+  @Override
+  public boolean isSeekable() {
+    return true;
+  }
+
+  @Override
   public long getDurationUs() {
     long numFrames = dataSize / blockAlignment;
     return (numFrames * C.MICROS_PER_SECOND) / sampleRateHz;
   }
 
+  @Override
+  public long getPosition(long timeUs) {
+    long unroundedPosition = (timeUs * averageBytesPerSecond) / C.MICROS_PER_SECOND;
+    // Round down to nearest frame.
+    long position = (unroundedPosition / blockAlignment) * blockAlignment;
+    return Math.min(position, dataSize - blockAlignment) + dataStartPosition;
+  }
+
+  // Misc getters.
+
+  /**
+   * Returns the time in microseconds for the given position in bytes.
+   *
+   * @param position The position in bytes.
+   */
+  public long getTimeUs(long position) {
+    return position * C.MICROS_PER_SECOND / averageBytesPerSecond;
+  }
+
   /** Returns the bytes per frame of this WAV. */
   public int getBytesPerFrame() {
     return blockAlignment;
@@ -75,33 +120,8 @@ import com.google.android.exoplayer2.C;
     return numChannels;
   }
 
-  /** Returns the position in bytes in this WAV for the given time in microseconds. */
-  public long getPosition(long timeUs) {
-    long unroundedPosition = (timeUs * averageBytesPerSecond) / C.MICROS_PER_SECOND;
-    // Round down to nearest frame.
-    long position = (unroundedPosition / blockAlignment) * blockAlignment;
-    return Math.min(position, dataSize - blockAlignment) + dataStartPosition;
-  }
-
-  /** Returns the time in microseconds for the given position in bytes in this WAV. */
-  public long getTimeUs(long position) {
-    return position * C.MICROS_PER_SECOND / averageBytesPerSecond;
-  }
-
-  /** Returns true if the data start position and size have been set. */
-  public boolean hasDataBounds() {
-    return dataStartPosition != 0 && dataSize != 0;
-  }
-
-  /** Sets the start position and size in bytes of sample data in this WAV. */
-  public void setDataBounds(long dataStartPosition, long dataSize) {
-    this.dataStartPosition = dataStartPosition;
-    this.dataSize = dataSize;
-  }
-
   /** Returns the PCM encoding. **/
-  @C.PcmEncoding
-  public int getEncoding() {
+  public @C.PcmEncoding int getEncoding() {
     return encoding;
   }