how to extract values from below xml code using java? Here I want to extract to,from,body,thread values using java. Here total code is condider as string.
<message to="[email protected]/Smack"
from="[email protected]"
type="chat">
<body>sai</body>
<thread>NNLWF1</thread>
<active xmlns="http://jabber.org/protocol/chatstates" />
</message>
One possibility would be to use Java's in built XPath capabailities, for example...
try {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document document = db.parse(new File("Test.xml"));
XPath xPath = XPathFactory.newInstance().newXPath();
XPathExpression expression = xPath.compile("/message[@from]");
Node node = (Node)expression.evaluate(document, XPathConstants.NODE);
System.out.println("From: " + node.getAttributes().getNamedItem("from").getNodeValue());
expression = xPath.compile("/message/body");
node = (Node)expression.evaluate(document, XPathConstants.NODE);
System.out.println("Body: " + node.getTextContent());
expression = xPath.compile("/message/thread");
node = (Node)expression.evaluate(document, XPathConstants.NODE);
System.out.println("Thread: " + node.getTextContent());
} catch (ParserConfigurationException | SAXException | IOException | DOMException | XPathExpressionException exp) {
exp.printStackTrace();
}
Which outputs...
From: [email protected]
Body: sai
Thread: NNLWF1
Take a look at:
For more details
String xmlString="<message>....</message>";//above xml code
JAXBContext jc = JAXBContext.newInstance( message.class );
Unmarshaller u = jc.createUnmarshaller();
message o =(message) u.unmarshal( new StreamSource( new StringReader(xmlString ) ) );
System.out.println("------getTo-------"+o.getTo());
System.out.println("------getFrom-------"+o.getFrom());
System.out.println("------getBody-------"+o.getBody());
System.out.println("------getThread-------"+o.getThread());
And Bean class(message) code.
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement
public class message {
public message(){}
private String to;
@XmlAttribute
public String getTo() {
return to;
}
public void setTo(String to) {
this.to = to;
}
@XmlAttribute
public String getFrom() {
return from;
}
public void setFrom(String from) {
this.from = from;
}
@XmlElement
public String getBody() {
return body;
}
public void setBody(String body) {
this.body = body;
}
@XmlElement
public String getThread() {
return thread;
}
public void setThread(String thread) {this.thread = thread;
}
private String from;
private String body;
private String thread;
public message(String to, String from, String body,String thread ){
super();
this.to = to;
this.from = from;
this.body = body;
this.thread = thread;
}
}
One way you can read your XML in java is:
import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
public class Demo {
public static void main(String[] args) throws Exception {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document document = db.parse(new File("yourFile.xml"));
NodeList nodeList = document.getElementsByTagName("message");
for(int x=0,size= nodeList.getLength(); x<size; x++) {
System.out.println(nodeList.item(x).getAttributes().getNamedItem("to").getNodeValue());
}
}
}
Hope it helps.
Here a complete example using a data projection library:
public class DataProjection {
public interface Message {
@XBRead("/message/@to")
String getTo();
@XBRead("/message/@from")
String getFrom();
@XBRead("/message/body")
String getBody();
@XBRead("/message/thread")
String getThread();
}
public static void main(String[] args) {
String xml="<message to=\"[email protected]/Smack\" \n" +
"from=\"[email protected]\" \n" +
"type=\"chat\">\n" +
"<body>sai</body>\n" +
"<thread>NNLWF1</thread>\n" +
"<active xmlns=\"http://jabber.org/protocol/chatstates\" />\n" +
"</message>";
Message message = new XBProjector().projectXMLString(xml, Message.class);
System.out.println(message.getFrom());
System.out.println(message.getTo());
System.out.println(message.getBody());
System.out.println(message.getThread());
}
This program prints out:
[email protected]
[email protected]/Smack
sai
NNLWF1
