All classes that implement FormatterInterface in RESTful 7.2

class \Drupal\restful\Plugin\formatter\Formatter extends \Drupal\Component\Plugin\PluginBase implements FormatterInterface uses ConfigurablePluginTrait
class \Drupal\restful\Plugin\formatter\FormatterHalJson implements FormatterInterface
class \Drupal\restful\Plugin\formatter\FormatterJson implements FormatterInterface
class \Drupal\restful\Plugin\formatter\FormatterJsonApi implements FormatterInterface
class \Drupal\restful\Plugin\formatter\FormatterSingleJson
class \Drupal\restful_example\Plugin\formatter\FormatterHalXml implements FormatterInterface

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