Java で XML を迅速かつ効率的に JSON に変換するにはどうすればよいですか?

<dependency>
  <groupId>org.json</groupId>
  <artifactId>json</artifactId>
  <version>20180813</version>
</dependency>

import com.fasterxml.jackson.dataformat.xml.XmlMapper;
import com.fasterxml.jackson.databind.JsonNode;

public class JacksonExample {

    public static void main(String[] args) throws IOException {
        String xml = "<test attrib=\"moretest\">Turn this to JSON</test>";
        XmlMapper xmlMapper = new XmlMapper();
        JsonNode jsonNode = xmlMapper.readTree(xml);
        String json = xmlMapper.writeValueAsString(jsonNode);
        System.out.println(json);
    }
}

import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
import com.google.gson.Gson;

public class JaxbExample {

    public static void main(String[] args) throws Exception {
        String xml = "<test attrib=\"moretest\">Turn this to JSON</test>";
        JAXBContext context = JAXBContext.newInstance(Test.class);
        Unmarshaller unmarshaller = context.createUnmarshaller();
        Test test = (Test) unmarshaller.unmarshal(new StringReader(xml));
        Gson gson = new Gson();
        String json = gson.toJson(test);
        System.out.println(json);
    }
}