public Object get(AnnotationClass annotationClass,String key) {
        Annotations annotations = get(annotationClass);
        if(annotations != null) {
            return annotations.get(key);
        } else {
            return null;
        }
    }
Gets the value of a property set on an annotation.
If the annotation or the key/value pair does not exists, null
is returned.
container-search/src/main/java/com/yahoo/text/interpretation/Interpretation.java