class MasterBackendVideoDataStore implements VideoDataStore {

    @Override
    public Observable<List<VideoMetadataInfoEntity>> getCategory( final String category ) {
        Log.d( TAG, "getCategory : enter" );

        Log.d( TAG, "getCategory : category=" + category );

        return this.api.getVideoList( null, null, false, -1, -1 )
                .flatMap( Observable::from )
                .filter( entity -> entity.contentType().equals( category ) )
                .toSortedList( ( entity1, entity2 ) -> entity1.title().compareTo( entity2.title() ) )
                .doOnNext( entity -> Log.d( TAG, "getCategory : entity=" + entity ) );

    }

    public  MasterBackendVideoDataStore( VideoApi api );

}