Java import android.support.v4.media.app.NotificationCompat.MediaStyle;

The MediaStyle class is a part of the Android Support Library v4 and is used to style a notification as a media notification, which is a type of notification that is used to display information about media playback.

To use the MediaStyle class, you will first need to include the Android Support Library v4 in your project. You can do this by adding the following dependency to your build.gradle file:

implementation 'com.android.support:support-v4:28.0.0'

Once you have included the library in your project, you can use the MediaStyle class as follows:

import android.support.v4.media.app.NotificationCompat;
import android.support.v4.media.app.NotificationCompat.MediaStyle;

...

NotificationCompat.Builder builder = new NotificationCompat.Builder(this, CHANNEL_ID)
    .setSmallIcon(R.drawable.ic_notification)
    .setContentTitle("Title")
    .setContentText("Content text")
    .setStyle(new MediaStyle()
        .setShowActionsInCompactView(0, 1, 2)
        .setMediaSession(mediaSession.getSessionToken()));

In this example, we create a notification builder and set the style to a MediaStyle object. We then use the setShowActionsInCompactView method to specify which actions should be shown in the compact view of the notification and the setMediaSession method to set the MediaSession object that this notification belongs to.

For more information about media notifications and the MediaStyle class, you can refer to the Android documentation.