deserialize json string with gson

arraylist, gson, java, json, jsp

Solution

I solved with this code:

String lista = (String)request.getAttribute("lista");
Gson gson = new Gson();                         
Type listType = new TypeToken<ArrayList<Utente>>() {}.getType();
ArrayList<Utente> users = new Gson().fromJson(lista, listType);

Problem

My java servlet returns a json string in this way: ``` Gson gson = new Gson(); String lista = gson.toJson(utenti); System.out.println(lista); request.setAttribute("lista", lista); request.getRequestDispatcher("GestioneUtenti.jsp").forward(request, response); ``` now, in the jsp page I want to have my arrayList again. I try to do this: ``` <% String lista = (String)request.getAttribute("lista"); Gson gson = new Gson(); ArrayList<Utente> users = gson.fromJson(lista, TypeToken.get(new ArrayList<Utente>().getClass()).getType()); out.println(users.get(0).getUsername()); %> ``` I have this exception: ``` java.lang.ClassCastException: com.google.gson.internal.StringMap cannot be cast to classi.Utente ``` can Youu help me? If i miss some particulars tell me! thanks :-)

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