Java Array list adding only 1 item(the last key)while iterating over keys in a JSON object

Question

So I'm trying to get all the keys within a specific JSON Object but only the last key is obtained.

   public void setUpSearch(JSONObject data_json){

    Iterator<String> keys = data_json.keys();
    while (keys.hasNext()) {
        //get the key
        String key = keys.next();
        scripts = new ArrayList<String>();
        scripts.add(key);
        Log.i(TAG, key);
        Log.i(TAG, String.valueOf(scripts));
    }

Logtagging key shows all keys (around 300 of em), however logtagging scripts shows only the last one.

Any help will be highly appreciated.

Answer 1

Because there is a BUG in your code. ArrayList initialization should be outside loop, otherwise you're overwriting previous one every time.

Use below code:

public void setUpSearch(JSONObject data_json){

    Iterator<String> keys = data_json.keys();
     scripts = new ArrayList<String>();

    while (keys.hasNext()) {
        //get the key
        String key = keys.next();
        scripts.add(key);
        Log.i(TAG, key);
        Log.i(TAG, String.valueOf(scripts));
    }