static boolean isHadoopWritable(Class<?> typeClass) {
		// check if this is directly the writable interface
		if (typeClass.getName().equals(HADOOP_WRITABLE_CLASS)) {
			return false;
		}

		final HashSet<Class<?>> alreadySeen = new HashSet<>();
		alreadySeen.add(typeClass);
		return hasHadoopWritableInterface(typeClass, alreadySeen);
	}
static boolean isHadoopWritable ( Class < ? > typeClass ) { if ( typeClass . getName ( ) . equals ( HADOOP_WRITABLE_CLASS ) ) { return false ; } final HashSet < Class < ? > > alreadySeen = new HashSet < > ( ) ; alreadySeen . add ( typeClass ) ; return hasHadoopWritableInterface ( typeClass , alreadySeen ) ; }
visible for testing