如何在后台线程中打开URL，以便解析XML并获取值

import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

public class XMLParser {
    public static void main(String[] args) {
        Thread thread = new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    // 打开URL连接
                    URL url = new URL("http://example.com/data.xml");
                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();
                    connection.setRequestMethod("GET");
                    connection.connect();

                    // 获取XML数据流
                    InputStream inputStream = connection.getInputStream();

                    // 创建DOM解析器
                    DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
                    DocumentBuilder builder = factory.newDocumentBuilder();

                    // 解析XML数据
                    Document document = builder.parse(inputStream);

                    // 获取根节点
                    Node root = document.getDocumentElement();

                    // 获取所需的值
                    NodeList nodeList = root.getChildNodes();
                    for (int i = 0; i < nodeList.getLength(); i++) {
                        Node node = nodeList.item(i);
                        if (node.getNodeType() == Node.ELEMENT_NODE) {
                            String value = node.getTextContent();
                            System.out.println(value);
                        }
                    }

                    // 关闭连接和流
                    inputStream.close();
                    connection.disconnect();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });

        // 启动后台线程
        thread.start();
    }
}