How to Extract Array Elements from a JSON Object in Java?

Extracting Array Elements from JSON in Java

Parsing JSON data into accessible Java objects can be a challenge, especially when dealing with nested structures. Consider the task of extracting interest keys from a JSON object like this:

member = "{interests : [{interestKey:Dogs}, {interestKey:Cats}]}";

To achieve this in Java, we can leverage the power of the org.json library. Let's dive into the code:

import org.json.JSONObject;
import org.json.JSONArray;
import java.util.List;
import java.util.ArrayList;

JSONObject obj = new JSONObject("{interests : [{interestKey:Dogs}, {interestKey:Cats}]}");

List<String> list = new ArrayList<String>();
JSONArray array = obj.getJSONArray("interests");
for(int i = 0 ; i < array.length() ; i++){
    list.add(array.getJSONObject(i).getString("interestKey"));
}

This code performs the following steps:

1. Creates a new JSONObject object from the provided JSON string.
2. Retrieves the "interests" array from the JSON object as a JSONArray object.
3. Iterates through the JSONArray and extracts the "interestKey" string from each JSONObject.
4. Adds the extracted "interestKey" string to a list of strings.

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