replace extension with mime type

This change uses mime types in a functionally equivalent way to how we used the extension hint so far.

Using a mimeType instead of the extension has some advantages. Most importantly mimeTypes are used by the cast SDK with which we want to achieve interoperability in the cast extension.

Using a mimeType instead of the extension hint further appears to be a bit more clear (which might be opinionated). Further mime types are a well known and widely used concept to identify file type on the internet and it provides asterix based generalizations (audio/*, */*) which could express the media type OTHER that ExoPlayer is using internally (no usage of asterix required so far though).

PiperOrigin-RevId: 300058945

demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -473,9 +473,7 @@ public class PlayerActivity extends AppCompatActivity
   @Nullable
   private MediaSource createLeafMediaSource(UriSample parameters) {
     MediaItem.Builder builder = new MediaItem.Builder().setSourceUri(parameters.uri);
-    if (parameters.extension != null) {
+    builder.setMimeType(Sample.inferAdaptiveStreamMimeType(parameters.uri, parameters.extension));
-      builder.setExtension(parameters.extension);
-    }
     int[] drmSessionForClearTypes = new int[0];
     HttpDataSource.Factory drmDataSourceFactory = null;
     if (parameters.drmInfo != null) {

demos/main/src/main/java/com/google/android/exoplayer2/demo/Sample.java

@@ -35,6 +35,7 @@ import android.net.Uri;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.util.Assertions;
+import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.Util;
 import java.util.ArrayList;
 import java.util.HashSet;
@@ -42,6 +43,31 @@ import java.util.UUID;
 
 /* package */ abstract class Sample {
 
+  /**
+   * Returns the mime type which is one of {@link MimeTypes#APPLICATION_MPD} for DASH, {@link
+   * MimeTypes#APPLICATION_M3U8} for HLS, {@link MimeTypes#APPLICATION_SS} for SmoothStreaming or
+   * {@code null} for all other streams.
+   *
+   * @param uri The uri of the stream.
+   * @param extension The extension
+   * @return The adaptive mime type or {@code null} for non-adaptive streams.
+   */
+  @Nullable
+  public static String inferAdaptiveStreamMimeType(Uri uri, @Nullable String extension) {
+    @C.ContentType int contentType = Util.inferContentType(uri, extension);
+    switch (contentType) {
+      case C.TYPE_DASH:
+        return MimeTypes.APPLICATION_MPD;
+      case C.TYPE_HLS:
+        return MimeTypes.APPLICATION_M3U8;
+      case C.TYPE_SS:
+        return MimeTypes.APPLICATION_SS;
+      case C.TYPE_OTHER:
+      default:
+        return null;
+    }
+  }
+
   public static final class UriSample extends Sample {
 
     public static UriSample createFromIntent(Uri uri, Intent intent, String extrasKeySuffix) {

library/core/src/main/java/com/google/android/exoplayer2/MediaItem.java

@@ -55,7 +55,7 @@ public final class MediaItem {
 
     @Nullable private String mediaId;
     @Nullable private Uri sourceUri;
-    @Nullable private String extension;
+    @Nullable private String mimeType;
     @Nullable private Uri drmLicenseUri;
     private Map<String, String> drmLicenseRequestHeaders;
     @Nullable private UUID drmUuid;
@@ -70,7 +70,7 @@ public final class MediaItem {
     }
 
     /**
-     * Sets the optional media id which identifies the media item. If not specified, {@code
+     * Sets the optional media id which identifies the media item. If not specified, {@link
      * #setSourceUri} must be called and the string representation of {@link
      * PlaybackProperties#sourceUri} is used as the media id.
      */
@@ -96,16 +96,17 @@ public final class MediaItem {
     }
 
     /**
-     * Sets the optional extension of the item.
+     * Sets the optional mime type.
      *
-     * <p>The extension can be used to disambiguate media items that have a uri which does not allow
+     * <p>The mime type may be used as a hint for inferring the type of the media item.
-     * to infer the actual media type.
      *
-     * <p>If a {@link PlaybackProperties#sourceUri} is set, the extension is used to create a {@link
+     * <p>If a {@link PlaybackProperties#sourceUri} is set, the mime type is used to create a {@link
      * PlaybackProperties} object. Otherwise it will be ignored.
+     *
+     * @param mimeType The mime type.
      */
-    public Builder setExtension(@Nullable String extension) {
+    public Builder setMimeType(@Nullable String mimeType) {
-      this.extension = extension;
+      this.mimeType = mimeType;
       return this;
     }
 
@@ -208,7 +209,7 @@ public final class MediaItem {
         playbackProperties =
             new PlaybackProperties(
                 sourceUri,
-                extension,
+                mimeType,
                 drmUuid != null
                     ? new DrmConfiguration(
                         drmUuid, drmLicenseUri, drmLicenseRequestHeaders, drmMultiSession)
@@ -291,12 +292,12 @@ public final class MediaItem {
     public final Uri sourceUri;
 
     /**
-     * The optional extension of the item, or {@code null} if unspecified.
+     * The optional mime type of the item, or {@code null} if unspecified.
      *
-     * <p>The extension can be used to disambiguate media items that have a uri which does not allow
+     * <p>The mime type can be used to disambiguate media items that have a uri which does not allow
      * to infer the actual media type.
      */
-    @Nullable public final String extension;
+    @Nullable public final String mimeType;
 
     /** Optional {@link DrmConfiguration} for the media. */
     @Nullable public final DrmConfiguration drmConfiguration;
@@ -313,12 +314,12 @@ public final class MediaItem {
 
     public PlaybackProperties(
         Uri sourceUri,
-        @Nullable String extension,
+        @Nullable String mimeType,
         @Nullable DrmConfiguration drmConfiguration,
         List<StreamKey> streamKeys,
         @Nullable Object tag) {
       this.sourceUri = sourceUri;
-      this.extension = extension;
+      this.mimeType = mimeType;
       this.drmConfiguration = drmConfiguration;
       this.streamKeys = streamKeys;
       this.tag = tag;
@@ -335,7 +336,7 @@ public final class MediaItem {
       PlaybackProperties other = (PlaybackProperties) obj;
 
       return sourceUri.equals(other.sourceUri)
-          && Util.areEqual(extension, other.extension)
+          && Util.areEqual(mimeType, other.mimeType)
           && Util.areEqual(drmConfiguration, other.drmConfiguration)
           && Util.areEqual(streamKeys, other.streamKeys)
           && Util.areEqual(tag, other.tag);
@@ -344,7 +345,7 @@ public final class MediaItem {
     @Override
     public int hashCode() {
       int result = sourceUri.hashCode();
-      result = 31 * result + (extension == null ? 0 : extension.hashCode());
+      result = 31 * result + (mimeType == null ? 0 : mimeType.hashCode());
       result = 31 * result + (drmConfiguration == null ? 0 : drmConfiguration.hashCode());
       result = 31 * result + streamKeys.hashCode();
       result = 31 * result + (tag == null ? 0 : tag.hashCode());

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

@@ -16,6 +16,7 @@
 package com.google.android.exoplayer2.source;
 
 import android.content.Context;
+import android.net.Uri;
 import android.util.SparseArray;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
@@ -34,6 +35,7 @@ import com.google.android.exoplayer2.upstream.DefaultLoadErrorHandlingPolicy;
 import com.google.android.exoplayer2.upstream.HttpDataSource;
 import com.google.android.exoplayer2.upstream.LoadErrorHandlingPolicy;
 import com.google.android.exoplayer2.util.Assertions;
+import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.Util;
 import java.util.Arrays;
 import java.util.List;
@@ -47,19 +49,20 @@ import java.util.Map;
  *
  * <ul>
  *   <li>{@code DashMediaSource.Factory} if the item's {@link MediaItem.PlaybackProperties#sourceUri
- *       sourceUri} ends in '.mpd' or if its {@link MediaItem.PlaybackProperties#extension extension
+ *       sourceUri} ends in '.mpd' or if its {@link MediaItem.PlaybackProperties#mimeType mimeType
- *       field} is explicitly set to 'mpd' (Requires the <a
+ *       field} is explicitly set to {@link MimeTypes#APPLICATION_MPD} (Requires the <a
  *       href="https://exoplayer.dev/hello-world.html#add-exoplayer-modules">exoplayer-dash module
  *       to be added</a> to the app).
  *   <li>{@code HlsMediaSource.Factory} if the item's {@link MediaItem.PlaybackProperties#sourceUri
- *       sourceUri} ends in '.m3u8' or if its {@link MediaItem.PlaybackProperties#extension
+ *       sourceUri} ends in '.m3u8' or if its {@link MediaItem.PlaybackProperties#mimeType mimeType
- *       extension field} is explicitly set to 'hls' (Requires the <a
+ *       field} is explicitly set to {@link MimeTypes#APPLICATION_M3U8} (Requires the <a
  *       href="https://exoplayer.dev/hello-world.html#add-exoplayer-modules">exoplayer-hls module to
  *       be added</a> to the app).
  *   <li>{@code SsMediaSource.Factory} if the item's {@link MediaItem.PlaybackProperties#sourceUri
  *       sourceUri} ends in '.ism', '.ism/Manifest' or if its {@link
- *       MediaItem.PlaybackProperties#extension extension field} is explicitly set to 'ism'
+ *       MediaItem.PlaybackProperties#mimeType mimeType field} is explicitly set to {@link
- *       (Requires the <a href="https://exoplayer.dev/hello-world.html#add-exoplayer-modules">
+ *       MimeTypes#APPLICATION_SS} (Requires the <a
+ *       href="https://exoplayer.dev/hello-world.html#add-exoplayer-modules">
  *       exoplayer-smoothstreaming module to be added</a> to the app).
  *   <li>{@link ProgressiveMediaSource.Factory} serves as a fallback if the item's {@link
  *       MediaItem.PlaybackProperties#sourceUri sourceUri} doesn't match one of the above. It tries
@@ -231,8 +234,8 @@ public final class DefaultMediaSourceFactory implements MediaSourceFactory {
     Assertions.checkNotNull(mediaItem.playbackProperties);
     @C.ContentType
     int type =
-        Util.inferContentType(
+        inferContentType(
-            mediaItem.playbackProperties.sourceUri, mediaItem.playbackProperties.extension);
+            mediaItem.playbackProperties.sourceUri, mediaItem.playbackProperties.mimeType);
     @Nullable MediaSourceFactory mediaSourceFactory = mediaSourceFactories.get(type);
     Assertions.checkNotNull(
         mediaSourceFactory, "No suitable media source factory found for content type: " + type);
@@ -311,4 +314,20 @@ public final class DefaultMediaSourceFactory implements MediaSourceFactory {
     factories.put(C.TYPE_OTHER, new ProgressiveMediaSource.Factory(dataSourceFactory));
     return factories;
   }
+
+  private static int inferContentType(Uri sourceUri, @Nullable String mimeType) {
+    if (mimeType == null) {
+      return Util.inferContentType(sourceUri);
+    }
+    switch (mimeType) {
+      case MimeTypes.APPLICATION_MPD:
+        return C.TYPE_DASH;
+      case MimeTypes.APPLICATION_M3U8:
+        return C.TYPE_HLS;
+      case MimeTypes.APPLICATION_SS:
+        return C.TYPE_SS;
+      default:
+        return Util.inferContentType(sourceUri);
+    }
+  }
 }

library/core/src/test/java/com/google/android/exoplayer2/MediaItemTest.java

@@ -21,6 +21,7 @@ import static org.junit.Assert.assertThrows;
 import android.net.Uri;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import com.google.android.exoplayer2.offline.StreamKey;
+import com.google.android.exoplayer2.util.MimeTypes;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -58,18 +59,21 @@ public class MediaItemTest {
   }
 
   @Test
-  public void builderSetExtension_isNullByDefault() {
+  public void builderSetMimeType_isNullByDefault() {
     MediaItem mediaItem = MediaItem.fromUri(URI_STRING);
 
-    assertThat(mediaItem.playbackProperties.extension).isNull();
+    assertThat(mediaItem.playbackProperties.mimeType).isNull();
   }
 
   @Test
-  public void builderSetExtension_setsExtension() {
+  public void builderSetMimeType_setsMimeType() {
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_STRING).setExtension("mpd").build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_STRING)
+            .setMimeType(MimeTypes.APPLICATION_MPD)
+            .build();
 
-    assertThat(mediaItem.playbackProperties.extension).isEqualTo("mpd");
+    assertThat(mediaItem.playbackProperties.mimeType).isEqualTo(MimeTypes.APPLICATION_MPD);
   }
 
   @Test

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

@@ -31,11 +31,10 @@ public final class DefaultMediaSourceFactoryTest {
   private static final String URI_MEDIA = "http://exoplayer.dev/video";
 
   @Test
-  public void createMediaSource_withExtension_progressiveSource() {
+  public void createMediaSource_withoutMimeType_progressiveSource() {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
-    MediaItem mediaItem =
+    MediaItem mediaItem = new MediaItem.Builder().setSourceUri(URI_MEDIA).build();
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("mp4").build();
 
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);
 

library/dash/src/test/java/com/google/android/exoplayer2/source/dash/DefaultMediaSourceFactoryTest.java

@@ -23,6 +23,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.MediaItem;
 import com.google.android.exoplayer2.source.DefaultMediaSourceFactory;
 import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.util.MimeTypes;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -33,11 +34,14 @@ public class DefaultMediaSourceFactoryTest {
   private static final String URI_MEDIA = "http://exoplayer.dev/video";
 
   @Test
-  public void createMediaSource_withExtension_dashSource() {
+  public void createMediaSource_withMimeType_dashSource() {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("mpd").build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_MEDIA)
+            .setMimeType(MimeTypes.APPLICATION_MPD)
+            .build();
 
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);
 
@@ -50,7 +54,11 @@ public class DefaultMediaSourceFactoryTest {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("mpd").setTag(tag).build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_MEDIA)
+            .setMimeType(MimeTypes.APPLICATION_MPD)
+            .setTag(tag)
+            .build();
 
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);
 

library/hls/src/test/java/com/google/android/exoplayer2/source/hls/DefaultMediaSourceFactoryTest.java

@@ -23,6 +23,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.MediaItem;
 import com.google.android.exoplayer2.source.DefaultMediaSourceFactory;
 import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.util.MimeTypes;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -33,11 +34,14 @@ public class DefaultMediaSourceFactoryTest {
   private static final String URI_MEDIA = "http://exoplayer.dev/video";
 
   @Test
-  public void createMediaSource_withExtension_hlsSource() {
+  public void createMediaSource_withMimeType_hlsSource() {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("m3u8").build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_MEDIA)
+            .setMimeType(MimeTypes.APPLICATION_M3U8)
+            .build();
 
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);
 
@@ -50,7 +54,11 @@ public class DefaultMediaSourceFactoryTest {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("m3u8").setTag(tag).build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_MEDIA)
+            .setMimeType(MimeTypes.APPLICATION_M3U8)
+            .setTag(tag)
+            .build();
 
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);
 

library/smoothstreaming/src/test/java/com/google/android/exoplayer2/source/smoothstreaming/DefaultMediaSourceFactoryTest.java

@@ -23,6 +23,7 @@ import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.MediaItem;
 import com.google.android.exoplayer2.source.DefaultMediaSourceFactory;
 import com.google.android.exoplayer2.source.MediaSource;
+import com.google.android.exoplayer2.util.MimeTypes;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 
@@ -35,11 +36,14 @@ public class DefaultMediaSourceFactoryTest {
   private static final String URI_MEDIA = "http://exoplayer.dev/video";
 
   @Test
-  public void createMediaSource_withExtension_smoothstreamingSource() {
+  public void createMediaSource_withMimeType_smoothstreamingSource() {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("ism").build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_MEDIA)
+            .setMimeType(MimeTypes.APPLICATION_SS)
+            .build();
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);
     assertThat(mediaSource).isInstanceOf(SsMediaSource.class);
   }
@@ -50,7 +54,11 @@ public class DefaultMediaSourceFactoryTest {
     DefaultMediaSourceFactory defaultMediaSourceFactory =
         DefaultMediaSourceFactory.newInstance(ApplicationProvider.getApplicationContext());
     MediaItem mediaItem =
-        new MediaItem.Builder().setSourceUri(URI_MEDIA).setExtension("ism").setTag(tag).build();
+        new MediaItem.Builder()
+            .setSourceUri(URI_MEDIA)
+            .setMimeType(MimeTypes.APPLICATION_SS)
+            .setTag(tag)
+            .build();
 
     MediaSource mediaSource = defaultMediaSourceFactory.createMediaSource(mediaItem);