protected static void setAgePredictorClient(AgePredicterLocal agePredicter) {
        if (AgeRecogniser.agePredictor == null) {
            AgeRecogniser.agePredictor = agePredicter;
        }
    }
USED in test cases to mock response of AgeClassifier
tika-parsers/tika-parsers-ml/tika-age-recogniser/src/main/java/org/apache/tika/parser/recognition/AgeRecogniser.java