mapping a pojo with json via gson

1  class SaltPOJO {
2        @SerializedName("CODE")
3        private String code = null;
4        @SerializedName("USER")
5        private User user = null;
6        ...
7
8        class User {
9            @SerializedName("E_MAIL")
10            private String e_mail = null;
11            @SerializedName("SALT")
12            private String salt = null;