How google gson library can be used to parse given below json

Question

I have this JSON

{
    \"309\":{ \"productId\":309,  \"name\":\"Heat Gear Polo\"},
    \"315\":{ \"productId\":310,  \"name\":\"Nike\"},
    \"410\":{ \"productI         


        

Answer 1

public static void main(String[] args)
{
    try
    {
        Gson gson = new Gson();

        String json = "{\"309\":{ \"productId\":309,  \"name\":\"Heat Gear Polo\"},\"315\":{ \"productId\":310,  \"name\":\"Nike\"},\"410\":{ \"productId\":311,  \"name\":\"Armani\"}}";
        Type type = new TypeToken<Map<String, Product>>(){}.getType();
        Map<String, Product> myMap = gson.fromJson(json, type);
        System.out.println(myMap);
    }
    catch (Exception e)
    {
        // TODO: handle exception
    }
}

Answer 2

You need parse the whole JSON string as a Map<Integer, Product>, using TypeToken to specify the generic type. Here's some working code:

import java.lang.reflect.Type;
import java.util.Map;

import com.google.common.reflect.TypeToken;
import com.google.gson.Gson;

public class JsonTest {
  private static final String JSON = "{" +
    "\"309\":{ \"productId\":309,  \"name\":\"Heat Gear Polo\"}," +
    "\"315\":{ \"productId\":310,  \"name\":\"Nike\"},"+
    "\"410\":{ \"productId\":311,  \"name\":\"Armani\"}"+
  "}";

  public static void main(String... args) {
    Gson g = new Gson();
    Type type = new TypeToken<Map<Integer, Product>>(){}.getType();
    Map<Integer, Product> map = g.fromJson(JSON, type);

    System.out.println(map);
  }

  public static class Product
  {
     private int productId;
     private String name;

    @Override
    public String toString() {
      return String.format("Product [productId=%s, name=%s]", productId, name);
    }     
  }
}