Parse xml from httppost response

Question

During the execution of a http POST i store the response as a String response.

HttpResponse httpresponse = httpclient.execute(httppost);
HttpEntity resEntity = httpresponse.getEntity();
response = EntityUtils.toString(resEntity);

If I print response it looks like:

<?xml version="1.0" encoding="UTF-8"?>
<response status="ok">
<sessionID>lo8mdn7bientr71b5kn1kote90</sessionID>
</response>

I would like to store just the sessionID as a string. I've tried

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
InputSource is = new InputSource(new StringReader(xml));

and various methods like this but it won't let me run the code since DocumentBuildFactory and InputSource are invalid.

What should I be doing to extract specific strings from this XML?

Solution 1

This is just quick and dirty test. It worked for me.

import java.io.IOException;
import java.io.StringReader;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

public class Test {
    public static void main(String[] args) {
        String xml= "<?xml version=\"1.0\" encoding=\"UTF-8\"?><response status=\"ok\"><sessionID>lo8mdn7bientr71b5kn1kote90</sessionID></response>";
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        DocumentBuilder builder;
        InputSource is;
        try {
            builder = factory.newDocumentBuilder();
            is = new InputSource(new StringReader(xml));
            Document doc = builder.parse(is);
            NodeList list = doc.getElementsByTagName("sessionID");
            System.out.println(list.item(0).getTextContent());
        } catch (ParserConfigurationException e) {
        } catch (SAXException e) {
        } catch (IOException e) {
        }
    }
}

output: lo8mdn7bientr71b5kn1kote90

Solution 2

1. Use the DOM Parser.

Eg:

DocumentBuilderFactory odbf = DocumentBuilderFactory.newInstance();
 DocumentBuilder odb =  odbf.newDocumentBuilder();
            InputSource is = new InputSource(new StringReader(xml));
            Document odoc = odb.parse(is);
            odoc.getDocumentElement().normalize ();    // normalize text representation
            System.out.println ("Root element of the doc is " + odoc.getDocumentElement().getNodeName());
            NodeList LOP = odoc.getElementsByTagName("locations");
            int totalPersons =LOP.getLength();
            System.out.println("Total nos of locations:"+totalPersons);

            for(int s=0; s<LOP.getLength() ; s++)
            {
                Node FPN =LOP.item(s);
                if(FPN.getNodeType() == Node.ELEMENT_NODE)
                    {

                    Element latlon = (Element)FPN;                                                                

                    NodeList oNameList1 = latlon.getElementsByTagName("featured");                                       
                    Element firstNameElement = (Element)oNameList1.item(0);
                    NodeList textNList1 = firstNameElement.getChildNodes();
                    //this.setLocationId(((Node)textNList1.item(0)).getNodeValue().trim());    
                    featuredArr = changeToBoolean(((Node)textNList1.item(0)).getNodeValue().trim());                                    // value taken
                    System.out.println("#####The Parsed data#####");
                    System.out.println("featured : " + ((Node)textNList1.item(0)).getNodeValue().trim());           
                    System.out.println("#####The Parsed data#####");
     }

See this link for more details:

http://tutorials.jenkov.com/java-xml/dom.html