try {
    $response = (new \Jetifier\Jetifier('API_KEY'))
        ->setTitle('title') // title of notification
        ->setTopic('topic') // topic recipient
        ->send();
}catch (\Jetifier\Exceptions\JetifierException $ex){
    //Exception
}

$client = new Client('API_KEY');
$message = new Message();
$recipient = new Device('TOKEN');
$notification = new Notification();

$notification->setTitle('title');

$message->setRecipient($recipient)
    ->setNotification($notification)

$client->send($message);

$client = new Client('API_KEY');
$message = new Message();
$recipient = new Topic('topic_name');
$notification = new Notification();

$notification->setTitle('title');

$message->setRecipient($recipient)
    ->setNotification($notification)

$client->send($message);

$client = new Client('API_KEY');
$message = new Message();

$recipient = new Condition(new Topic('topic_name'));
$recipient->orTopic(new Topic('second_topic');

$notification = new Notification();
$notification->setTitle('title');

$message->setRecipient($recipient)
    ->setNotification($notification)

$client->send($message);

...

$recipient = new Condition(new Topic('topic_name'));
$subCondition = new Condition(new Topic('second_topic'));
$subCondition->orTopic(new Topic('third_topic');
$recipient->andCondition($subCondition);

...

$client = new Client('API_KEY');
$client->setSender(new \Jetifier\Sender\Post());

...