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 <p>This code performs the following steps:</p> <ol> <li>Creates a new JSONObject object from the provided JSON string.</li> <li>Retrieves the "interests" array from the JSON object as a JSONArray object.</li> <li>Iterates through the JSONArray and extracts the "interestKey" string from each JSONObject.</li> <li>Adds the extracted "interestKey" string to a list of strings.</li> </ol></string></string>
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