Серіалізувати в Json

1. Закачати gson-2.6.2.jar 

google.com/search - нова версія

2. Build Path -> Configure Build Path... -> Libraries -> Add External JARs

Gson gson = new Gson();

String json = gson.toJson(obj);

// {"FirstName":"Taras","LastName":"Shevchenko","year":1814}

Person objnew = gson.fromJson(json, Person.class); 

System.out.println(objnew.getFirstName() + " " + 

                            objnew.getLastName() + " " + objnew.GetYear());

// Taras Shevchenko 1814