Notifying the class doesn't restart the service

[mNantern]

After upgrading my java version I notify the class['logstash'] in order to restart it. But it's not working, the service is not restarted:

puppet agent -t
Info: Using configured environment 'production'
Info: Retrieving pluginfacts
Info: Retrieving plugin
Info: Loading facts
Info: Caching catalog for lst1.dev.hub.docapost.io
Info: Applying configuration version '1519642246'
Notice: /Stage[main]/Java/Package[java]/ensure: created
Info: /Stage[main]/Java/Package[java]: Scheduling refresh of Class[Logstash]
Notice: Applied catalog in 16.96 seconds

systemctl status logstash
● logstash.service - logstash
   Loaded: loaded (/etc/systemd/system/logstash.service; enabled; vendor preset: disabled)
   Active: active (running) since ven. 2018-02-23 08:23:46 CET; 3 days ago

I have to explicitly notify the service['logstash'] and so this doesn't work unfortunately:

class { '::logstash':
    startup_options => $init_defaults_hash,
    version         => $logstash_version,
    manage_repo     => false,
    logstash_user   => $generic_user,
    logstash_group  => $generic_group,
    settings => {
      'path.logs' => "/VAR/logstash/logs",
      'path.data' => "/VAR/logstash/data"
    },
    subscribe => Package['java']
  }

I have to use an ugly workaround:

exec { '/usr/bin/ls /':
    notify      => Service['logstash'],
    subscribe   => Package['java'],
    refreshonly => true
  }