GSON parse generic Json Array

Question

My question is very similiar to this: Unable to parse Json array using Gson

But I cann\'t get the answer from it. The answer from above link:

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Answer 1

I met the same problem. From the Javadoc of TypeToken:

This syntax cannot be used to create type literals that have wildcard parameters, such as Class<?> or List<? extends CharSequence>.

You must explicitly indicate the type of T in TypeToken<T>, without generics.

Answer 2

You can use this method in order to parse generic json string to map

    public Map<String, String> getMapFromJson(String jsonString) {
    Map<String, String> map = new HashMap<>();
    try {
        JSONObject object = new JSONObject(jsonString);
        Iterator<?> iterator = object.keys();
        while (iterator.hasNext()) {
            String key = (String) iterator.next();
            if(!key.isEmpty() && !object.getString(key).isEmpty()){
                map.put(key, object.getString(key));
            }
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
    return map;
}

Answer 3

you can do like this:

     Gson gson = new Gson();

    String jsonString = "[{\"id\":18,\"city\":\"test\",\"street\":\"test 1\",\"zipcode\":121209,\"state\":\"IL\",\"lat\":32.158138,\"lng\":34.807838},{\"id\":19,\"city\":\"test\",\"street\":\"1\",\"zipcode\":76812,\"state\":\"IL\",\"lat\":32.161041,\"lng\":34.810410}]";

    List<Map> tmpList = gson.fromJson(jsonString);
    List<T> resultList = new Arraylist<T>(tmplist.size());
    for(Map map:tmpList){
       String tmpJson = gson.toJson(map);
       resultList.add(gson.fromJson(tmpJson, classT));
    }
    return resultList;