List<Type> and java.lang.ClassCastException: com.google.gson.internal.StringMap

Question

Below my function,

public <T> List<T> jsonToListBean(String json, Class<T> clazz) {
    Gson gson = new Gson();     
    Type listType = new TypeToken<List<T>>(){}.getType();       
    List<T> returnValue = gson.fromJson(json, listType);
    return returnValue;
}

but the system returns this exception:

java.lang.ClassCastException: com.google.gson.internal.StringMap

I notice also that if I use the following line code

Type listType = new TypeToken<ArrayList<ShapeBean>>(){}.getType();

it works, but my target is to be absolutly as generic as possible to make my code more efficient.

How should i change my code to make usable also passing the type "T" instead the "ShapeBean"?

Answer 1

Solved. Thanks to kan's link below the code:

public <T> List<T> listEntity(String jsonCommand, Class<T> clazz) {

    List<T> lst =  new ArrayList<T>();
    try {
        // Consuming remote method
        JsonParser parser = new JsonParser();
        JsonArray array = parser.parse(jsonCommand).getAsJsonArray();

        for(final JsonElement json: array){
            Gson g = new Gson();
            T entity = g.fromJson(json, clazz);
            lst.add(entity);
        }
    } catch (Exception e) {
        e.printStackTrace();
    } return lst;
}

check also this: Gson TypeToken with dynamic ArrayList item type