Box has a list of Product public class Box { private Integer id; private String name; private List<Product> products = new ArrayList<Product>(); // getters and setters } I serialize the box instance to json, the result is {"box":{"id":"1","name":"box1","products":{"product":[ {"id":"1","name":"product1","price":"11.0"}, {"id":"3","name":"product3","price":"33.0"} ] }}} but what I want is( without alias of class name: "box" , "product") {"id":"1","name":"box1", "products": [ {"id":"1","name":"product1","price":"11.0"}, {"id":"3","name":"product3","price":"33.0"} ] } The tree of Ext requires the latter form So if possible, please provide a option to hide the class names, thanks