media3/extensions/cronet

ExoPlayer Cronet extension

The Cronet extension is an HttpDataSource implementation using Cronet.

Getting the extension

The easiest way to use the extension is to add it as a gradle dependency:

implementation 'com.google.android.exoplayer:extension-cronet:2.X.X'

where 2.X.X is the version, which must match the version of the ExoPlayer library being used.

Alternatively, you can clone the ExoPlayer repository and depend on the module locally. Instructions for doing this can be found in ExoPlayer's top level README.

Note that by default, the extension will use the Cronet implementation in Google Play Services. If you prefer, it's also possible to embed the Cronet implementation directly into your application. See below for more details.

Using the extension

ExoPlayer requests data through DataSource instances. These instances are either instantiated and injected from application code, or obtained from instances of DataSource.Factory that are instantiated and injected from application code.

If your application only needs to play http(s) content, using the Cronet extension is as simple as updating any DataSources and DataSource.Factory instantiations in your application code to use CronetDataSource and CronetDataSourceFactory respectively. If your application also needs to play non-http(s) content such as local files, use

new DefaultDataSource(
    ...
    new CronetDataSource(...) /* baseDataSource argument */);

and

new DefaultDataSourceFactory(
    ...
    new CronetDataSourceFactory(...) /* baseDataSourceFactory argument */);

respectively.

Choosing between Google Play Services Cronet and Cronet Embedded

The underlying Cronet implementation is available both via a Google Play Services API, and as a library that can be embedded directly into your application. When you depend on com.google.android.exoplayer:extension-cronet:2.X.X, the library will not be embedded into your application by default. The extension will attempt to use the Cronet implementation in Google Play Services. The benefits of this approach are:

• A negligible increase in the size of your application.
• The Cronet implementation is updated automatically by Google Play Services.

If Google Play Services is not available on a device, CronetDataSourceFactory will fall back to creating DefaultHttpDataSource instances, or HttpDataSource instances created by a fallbackFactory that you can specify.

It's also possible to embed the Cronet implementation directly into your application. To do this, add an additional gradle dependency to the Cronet Embedded library:

implementation 'com.google.android.exoplayer:extension-cronet:2.X.X'
implementation 'org.chromium.net:cronet-embedded:XX.XXXX.XXX'

where XX.XXXX.XXX is the version of the library that you wish to use. The extension will automatically detect and use the library. Embedding will add approximately 8MB to your application, however it may be suitable if:

• Your application is likely to be used in markets where Google Play Services is not widely available.
• You want to control the exact version of the Cronet implementation being used.

If you do embed the library, you can specify which implementation should be preferred if the Google Play Services implementation is also available. This is controlled by a preferGMSCoreCronet parameter, which can be passed to the CronetEngineWrapper constructor (GMS Core is another name for Google Play Services).

Links

• Javadoc: Classes matching com.google.android.exoplayer2.ext.cronet.* belong to this module.