UncatchedException.kt

class RecognitionException(
        override val message: String
) : Throwable()

class Recognizer(
        private val documentReder: DocumentReader  
) {
  
  fun recognize(image: Bitmap, callback: ((RecognitionResult) -> Unit)) {
        documentReader.recognizeImage(image) { action, results, error ->
            if (error != null) {
                throw RecognitionException(error)
            } else {
                callback.invoke(RecognitionResult(action, results))
            }
        }
    }
}

class DocPresenter(
      private val recognizer: Recognizer
) {
  
  private fun recognize(image: Bitmap) {
        try {
            recognizer.recognize(image) { result ->
                if (result.result.textResult == null) {
                    onNotRecognized()
                } else {
                    onRecognized(result.result)
                }
            }
        } catch (ex: RecognitionException) {
            XLogger.e(ex)
        }
    }