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 :-)
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);
It suggests you have a StringMap where you have declared a Utente class. The source of the error is more than likely your users list
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