Java cast Arraylist to JsonElement

Question

I would like use this method:

json.add("myText", getList(id));

The function getList(id) return an arraylist, but the method json.add would like a JsonElement.

So, how can i cast an arraylist in JsonElement ?

I test this, but it doesn't work:

json.add("myText", (JsonElement)getList(id));

I test this too:

JsonElement jelement = new JsonElement() {

 private ArrayList<String> list= new ArrayList<String>();

 public ArrayList<String> getList(){ 
     return this.list;
 } 

};

Answer 1

com.google.gson has methods for serializing an ArrayList (or any collection). Once you have serialized it, you can parse the string with a JSONParser:

JSONParser.parse(gson.toJson(getList(id)));

ref: https://sites.google.com/site/gson/gson-user-guide#TOC-Array-Examples

Answer 2

In order to get a JsonElement out of a List, you can use JsonTree:

List<String> myList = new ArrayList<>();
jsonObject.add("myList", gson.toJsonTree(myList));