IterableConverter does not override marshal, causes ClassCastException when iterable is NOT a Collection

    public void marshal(Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
        Collection collection = (Collection) source;
        for (Iterator iterator = collection.iterator(); iterator.hasNext();) {
            Object item = iterator.next();
            writeItem(item, context, writer);
        }
    }

        @Override
        public void marshal( final Object                     value,
                             final HierarchicalStreamWriter   writer,
                             final MarshallingContext         context ) {
            Iterable<?> it = (Iterable<?>) value;

            writer.startNode( "list" );
            for( Object o : it ) {
                context.convertAnother( o );
            }
            writer.endNode();
        }
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