Decouple ProgressiveMediaPeriod and ExtractorHolder

- Avoid having ExtractorHolder expose the underlying extractor.
- Make ProgressiveMP inject a DataSource instead of a DefaultExtractor.

This CL should introduce no functional changes.

PiperOrigin-RevId: 296944788

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

@@ -15,11 +15,16 @@
  */
 package com.google.android.exoplayer2.source;
 
-import android.net.Uri;
 import androidx.annotation.Nullable;
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.extractor.DefaultExtractorInput;
 import com.google.android.exoplayer2.extractor.Extractor;
 import com.google.android.exoplayer2.extractor.ExtractorInput;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
+import com.google.android.exoplayer2.extractor.PositionHolder;
+import com.google.android.exoplayer2.extractor.mp3.Mp3Extractor;
+import com.google.android.exoplayer2.upstream.DataSource;
+import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
 import java.io.EOFException;
 import java.io.IOException;
@@ -30,6 +35,7 @@ import java.io.IOException;
   private final Extractor[] extractors;
 
   @Nullable private Extractor extractor;
+  @Nullable private ExtractorInput extractorInput;
 
   /**
    * Creates a holder that will select an extractor and initialize it using the specified output.
@@ -41,36 +47,47 @@ import java.io.IOException;
   }
 
   /**
-   * Returns an initialized extractor for reading {@code input}, and returns the same extractor on
+   * Disables seeking in MP3 streams.
-   * later calls.
    *
-   * @param input The {@link ExtractorInput} from which data should be read.
+   * <p>MP3 live streams commonly have seekable metadata, despite being unseekable.
+   */
+  public void disableSeekingOnMp3Streams() {
+    if (extractor instanceof Mp3Extractor) {
+      ((Mp3Extractor) extractor).disableSeeking();
+    }
+  }
+
+  /**
+   * Initializes any necessary resources for extraction.
+   *
+   * @param dataSource The {@link DataSource} from which data should be read.
+   * @param position The initial position of the {@code dataSource} in the stream.
+   * @param length The length of the stream, or {@link C#LENGTH_UNSET} if it is unknown.
    * @param output The {@link ExtractorOutput} that will be used to initialize the selected
    *     extractor.
-   * @param uri The {@link Uri} of the data.
-   * @return An initialized extractor for reading {@code input}.
    * @throws UnrecognizedInputFormatException Thrown if the input format could not be detected.
    * @throws IOException Thrown if the input could not be read.
    * @throws InterruptedException Thrown if the thread was interrupted.
    */
-  public Extractor selectExtractor(ExtractorInput input, ExtractorOutput output, Uri uri)
+  public void init(DataSource dataSource, long position, long length, ExtractorOutput output)
       throws IOException, InterruptedException {
+    extractorInput = new DefaultExtractorInput(dataSource, position, length);
     if (extractor != null) {
-      return extractor;
+      return;
     }
     if (extractors.length == 1) {
       this.extractor = extractors[0];
     } else {
       for (Extractor extractor : extractors) {
         try {
-          if (extractor.sniff(input)) {
+          if (extractor.sniff(extractorInput)) {
             this.extractor = extractor;
             break;
           }
         } catch (EOFException e) {
           // Do nothing.
         } finally {
-          input.resetPeekPosition();
+          extractorInput.resetPeekPosition();
         }
       }
       if (extractor == null) {
@@ -78,17 +95,50 @@ import java.io.IOException;
             "None of the available extractors ("
                 + Util.getCommaDelimitedSimpleClassNames(extractors)
                 + ") could read the stream.",
-            uri);
+            Assertions.checkNotNull(dataSource.getUri()));
       }
     }
     extractor.init(output);
-    return extractor;
   }
 
+  /**
+   * Returns the current read position in the input stream, or {@link C#POSITION_UNSET} if no input
+   * is available.
+   */
+  public long getCurrentInputPosition() {
+    return extractorInput != null ? extractorInput.getPosition() : C.POSITION_UNSET;
+  }
+
+  /**
+   * Notifies the underlying extractor that a seek has occurred.
+   *
+   * @param position The byte offset in the stream from which data will be provided.
+   * @param seekTimeUs The seek time in microseconds.
+   */
+  public void seek(long position, long seekTimeUs) {
+    Assertions.checkNotNull(extractor).seek(position, seekTimeUs);
+  }
+
+  /**
+   * Extracts data starting at the current input stream position.
+   *
+   * @param positionHolder If {@link Extractor#RESULT_SEEK} is returned, this holder is updated to
+   *     hold the position of the required data.
+   * @return One of the {@link Extractor}{@code .RESULT_*} values.
+   * @throws IOException If an error occurred reading from the input.
+   * @throws InterruptedException If the thread was interrupted.
+   */
+  public int read(PositionHolder positionHolder) throws IOException, InterruptedException {
+    return Assertions.checkNotNull(extractor)
+        .read(Assertions.checkNotNull(extractorInput), positionHolder);
+  }
+
+  /** Releases any held resources. */
   public void release() {
     if (extractor != null) {
       extractor.release();
       extractor = null;
     }
+    extractorInput = null;
   }
 }

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

@@ -25,16 +25,13 @@ import com.google.android.exoplayer2.ParserException;
 import com.google.android.exoplayer2.SeekParameters;
 import com.google.android.exoplayer2.decoder.DecoderInputBuffer;
 import com.google.android.exoplayer2.drm.DrmSessionManager;
-import com.google.android.exoplayer2.extractor.DefaultExtractorInput;
 import com.google.android.exoplayer2.extractor.Extractor;
-import com.google.android.exoplayer2.extractor.ExtractorInput;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
 import com.google.android.exoplayer2.extractor.PositionHolder;
 import com.google.android.exoplayer2.extractor.SeekMap;
 import com.google.android.exoplayer2.extractor.SeekMap.SeekPoints;
 import com.google.android.exoplayer2.extractor.SeekMap.Unseekable;
 import com.google.android.exoplayer2.extractor.TrackOutput;
-import com.google.android.exoplayer2.extractor.mp3.Mp3Extractor;
 import com.google.android.exoplayer2.metadata.Metadata;
 import com.google.android.exoplayer2.metadata.icy.IcyHeaders;
 import com.google.android.exoplayer2.source.MediaSourceEventListener.EventDispatcher;
@@ -955,7 +952,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
     public void load() throws IOException, InterruptedException {
       int result = Extractor.RESULT_CONTINUE;
       while (result == Extractor.RESULT_CONTINUE && !loadCanceled) {
-        ExtractorInput input = null;
         try {
           long position = positionHolder.position;
           dataSpec = buildDataSpec(position);
@@ -963,7 +959,6 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
           if (length != C.LENGTH_UNSET) {
             length += position;
           }
-          Uri uri = Assertions.checkNotNull(dataSource.getUri());
           icyHeaders = IcyHeaders.parse(dataSource.getResponseHeaders());
           DataSource extractorDataSource = dataSource;
           if (icyHeaders != null && icyHeaders.metadataInterval != C.LENGTH_UNSET) {
@@ -971,23 +966,22 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
             icyTrackOutput = icyTrack();
             icyTrackOutput.format(ICY_FORMAT);
           }
-          input = new DefaultExtractorInput(extractorDataSource, position, length);
+          extractorHolder.init(extractorDataSource, position, length, extractorOutput);
-          Extractor extractor = extractorHolder.selectExtractor(input, extractorOutput, uri);
 
-          // MP3 live streams commonly have seekable metadata, despite being unseekable.
+          if (icyHeaders != null) {
-          if (icyHeaders != null && extractor instanceof Mp3Extractor) {
+            extractorHolder.disableSeekingOnMp3Streams();
-            ((Mp3Extractor) extractor).disableSeeking();
           }
 
           if (pendingExtractorSeek) {
-            extractor.seek(position, seekTimeUs);
+            extractorHolder.seek(position, seekTimeUs);
             pendingExtractorSeek = false;
           }
           while (result == Extractor.RESULT_CONTINUE && !loadCanceled) {
             loadCondition.block();
-            result = extractor.read(input, positionHolder);
+            result = extractorHolder.read(positionHolder);
-            if (input.getPosition() > position + continueLoadingCheckIntervalBytes) {
+            long currentInputPosition = extractorHolder.getCurrentInputPosition();
-              position = input.getPosition();
+            if (currentInputPosition > position + continueLoadingCheckIntervalBytes) {
+              position = currentInputPosition;
               loadCondition.close();
               handler.post(onContinueLoadingRequestedRunnable);
             }
@@ -995,8 +989,8 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
         } finally {
           if (result == Extractor.RESULT_SEEK) {
             result = Extractor.RESULT_CONTINUE;
-          } else if (input != null) {
+          } else if (extractorHolder.getCurrentInputPosition() != C.POSITION_UNSET) {
-            positionHolder.position = input.getPosition();
+            positionHolder.position = extractorHolder.getCurrentInputPosition();
           }
           Util.closeQuietly(dataSource);
         }