How I can add a property to a JSON was created GSON?

Question

I have the following class

public class OrderShoppingCart {
@Expose
@SerializedName("id")
private String _id;
@Expose
@SerializedName("quantity")
private int _quantity;
private String _description;
private String _name;
private int _price;
@Expose
@SerializedName("selections")
private List<SelectionShoppingCart> _selections;

public OrderShoppingCart(String id, int quantity, String description, String name,int price, List<SelectionShoppingCart> selections) {
    _id = id;
    _quantity = Integer.valueOf(quantity);
    _description = description;
    _name = name;
    _price = price;
    _selections = selections;
}
         //HERE GET AND SETTER
}

I built the GSON follows

Gson gson = new GsonBuilder().excludeFieldsWithoutExposeAnnotation().create();
                String jsonG = gson.toJson(OrderShoppingCart.getOrders());

//OrderShoppingCart.getOrders() return all atributes

And I got the following

[{"id":"525b207b16b1e9ca33000143","selections":[],"quantity":1}]

but I need this

{items:[{"id":"525b207b16b1e9ca33000143","selections":[],"quantity":1}]}

How I can add what I'm missing?

Answer 1

Try to create a JsonObject and add a member with name items and value your Json object.

Gson gson = new GsonBuilder().excludeFieldsWithoutExposeAnnotation().create();
JsonObject jObj = new JsonObject();
jObj.add("items", gson.toJson(OrderShoppingCart.getOrders()));
String jsonG = jObj.toString();