gwt解析xml

import com.google.gwt.xml.client.Document;import com.google.gwt.xml.client.Node;import com.google.gwt.xml.client.NodeList;import com.google.gwt.xml.client.XMLParser;private void parseMessage(String messageXml) {  try {    // parse the XML document into a DOM    Document messageDom = XMLParser.parse(messageXml);    // find the sender's display name in an attribute of the <from> tag    Node fromNode = messageDom.getElementsByTagName("from").item(0);    String from = ((Element)fromNode).getAttribute("displayName");    fromLabel.setText(from);    // get the subject using Node's getNodeValue() function    String subject = messageDom.getElementsByTagName("subject").item(0).getFirstChild().getNodeValue();    subjectLabel.setText(subject);    // get the message body by explicitly casting to a Text node    Text bodyNode = (Text)messageDom.getElementsByTagName("body").item(0).getFirstChild();    String body = bodyNode.getData();    bodyLabel.setText(body);  } catch (DOMException e) {    Window.alert("Could not parse XML document.");  }}