I am creating a JSON object in which i am adding a key and a value which is an array. The value for both key and value comes from a TreeSet which has data in sorted form. Ho
Even if this post is quite old, I thought it is worth posting an alternative without GSON:
First store your keys in an ArrayList, then sort it and loop through the ArrayList of keys:
Iterator<String> it= MyTreeSet.iterator();
ArrayList<String>keys = new ArrayList();
while (it.hasNext()) {
keys.add(it.next());
}
Collections.sort(keys);
for (int i = 0; i < keys.size(); i++) {
String country = keys.get(i);
System.out.println("----country"+country);
JSONArray jsonArray = new JSONArray();
jsonArray.put(country);
jsonArray.put("this");
jsonObj.put(country, jsonArray);
}
It works with Google Gson API. Try it out.
try{
TreeSet<String> MyTreeSet = new TreeSet<String>();
MyTreeSet.add("SPAIN");
MyTreeSet.add("TAIWNA");
MyTreeSet.add("INDIA");
MyTreeSet.add("JAPAN");
System.out.println(MyTreeSet);
Iterator<String> it= MyTreeSet.iterator();
JsonObject gsonObj = new JsonObject();
JSONObject jsonObj = new JSONObject();
while (it.hasNext()) {
String country = it.next();
System.out.println("----country"+country);
JSONArray jsonArray = new JSONArray();
jsonArray.put(country);
jsonArray.put("this");
jsonObj.put(country, jsonArray);
JsonArray gsonArray = new JsonArray();
gsonArray.add(new JsonPrimitive("country"));
gsonArray.add(new JsonPrimitive("this"));
gsonObj.add(country, gsonArray);
}
System.out.println(gsonObj.toString());
System.out.println(jsonObj.toString());
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Below are what the doc says from http://www.json.org/java/index.html.
"A JSONObject is an unordered collection of name/value pairs."
"A JSONArray is an ordered sequence of values. "
In order to get an sorted Json Object, you can use Gson which is already provided a good answer by @user748316.