* {@link Transformer} which accepts / transforms only specific classes of\r
* input, and is useful if the selection of transformer should be based on the\r
* class of the input and there is one-to-one mapping between input class and\r
* transformer.\r
* {@link Transformer} which accepts / transforms only specific classes of\r
* input, and is useful if the selection of transformer should be based on the\r
* class of the input and there is one-to-one mapping between input class and\r
* transformer.\r