CarAudioRecord

@RequiresCarApi(value = 5)
public abstract class CarAudioRecord

CarAudioRecord car = CarAudioRecord.create(carContext);
car.startRecording();

byte[] data = new byte[CarAudioRecord.AUDIO_CONTENT_BUFFER_SIZE];
while(car.read(data, 0, CarAudioRecord.AUDIO_CONTENT_BUFFER_SIZE) >= 0) {
    // Use data array
    // Potentially calling car.stopRecording() if your processing finds end of speech
}
car.stopRecording();

CarAudioRecord record = CarAudioRecord.create(carContext);
// Take audio focus so that user's media is not recorded
AudioAttributes audioAttributes =
        new AudioAttributes.Builder()
                .setContentType(AudioAttributes.CONTENT_TYPE_SPEECH)
                .setUsage(USAGE_ASSISTANCE_NAVIGATION_GUIDANCE)
                .build();

AudioFocusRequest audioFocusRequest =
        new AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE)
                .setAudioAttributes(audioAttributes)
                .setOnAudioFocusChangeListener(state -> {
                    if (state == AudioManager.AUDIOFOCUS_LOSS) {
                        // Stop recording if audio focus is lost
                        record.stopRecording();
                    }
                })
                .build();

if (mCarContext.getSystemService(AudioManager.class).requestAudioFocus(audioFocusRequest)
        != AUDIOFOCUS_REQUEST_GRANTED) {
    return;
}

record.startRecording();