JSON - parsing document with JSONArray in Java

Question

I'm parsing this document: http://pastebin.com/M3Gsbf1t as you can see it's kind of big. This document was generated by Youtube Data API v3. I want to get all "title" elements and display them. My code:

Object obj = parser.parse(str); // str contains the JSON code
JSONObject jsonObject = (JSONObject) obj;               
JSONArray msg = (JSONArray) jsonObject.get("title");
Iterator iterator = msg.iterator();
while (iterator.hasNext()) {
  System.out.println(iterator.next());
}

but it returns "NullPointerException". If I replace the "title" with the "items" it works fine but it returns me a lot of informations that I don't need. I'm using the JSON.simple library.

Thanks for help :)

Answer 1

This code should work:

    JSONObject jsonObject = (JSONObject) obj;               
    JSONArray msg = (JSONArray) jsonObject.get("items");
    Iterator iterator = msg.iterator();
    while (iterator.hasNext()) {
      //System.out.println(iterator.next());
      JSONObject item = (JSONObject) iterator.next();
      JSONObject item_snippet = (JSONObject) item.get("snippet");
      System.out.println( item_snippet.get("title"));
    }

You have a JSONObject at the root of your JSON string. In it, there's an JSONArray named items. From it you have to pull out individual items in while loop.

For each item there's JSONObject snippet nested in. Finally you'll find your title string in it.

Answer 2

jquery solution, this should give you an array of titles unless I am reading the object wrong.

  titles = [];
  obj = $.parseJSON(str);
  $.each(obj.items,function(i,v{
     titles.push(v.snippet.title);
  });

Answer 3

Should be something like this:

Object obj = parser.parse(str); // str contains the JSON code
JSONObject jsonObject = (JSONObject) obj;               
JSONArray msg = (JSONArray) jsonObject.get("items");
Iterator iterator = msg.iterator();
while (iterator.hasNext()) {
  // cast next item to JSONObject
  JSONObject item = (JSONObject) iterator.next();
  // grab the title
  System.out.println(item.get("title"));
}