如何将JSON对象转换为DBObject？

import com.mongodb.BasicDBObject;
import org.json.JSONObject;

public class JsonToDbObjectConverter {
    public static BasicDBObject convert(JSONObject json) {
        BasicDBObject dbObject = new BasicDBObject();

        for (String key : json.keySet()) {
            Object value = json.get(key);

            if (value instanceof JSONObject) {
                value = convert((JSONObject) value);
            }

            dbObject.append(key, value);
        }

        return dbObject;
    }

    public static void main(String[] args) {
        JSONObject json = new JSONObject("{\"name\": \"John\", \"age\": 30, \"address\": {\"city\": \"New York\", \"country\": \"USA\"}}");
        BasicDBObject dbObject = convert(json);
        System.out.println(dbObject);
    }
}