检索java中json对象的所有嵌套键。

import org.json.JSONObject;

public class JsonKeyRetriever {
    public static void main(String[] args) {
        String jsonString = "{\"name\":\"John\",\"age\":30,\"address\":{\"street\":\"123 Main St\",\"city\":\"New York\"}}";
        JSONObject jsonObject = new JSONObject(jsonString);
        
        retrieveKeys(jsonObject, "");
    }
    
    public static void retrieveKeys(JSONObject jsonObject, String parentKey) {
        for (String key : jsonObject.keySet()) {
            String currentKey = parentKey.isEmpty() ? key : parentKey + "." + key;
            System.out.println(currentKey);
            
            if (jsonObject.get(key) instanceof JSONObject) {
                retrieveKeys(jsonObject.getJSONObject(key), currentKey);
            }
        }
    }
}

name
age
address.street
address.city