XML Node Class in Salesforce

XmlNode Class:

Use the XmlNode class to work with a node in an XML document. The DOM represents an XML document as a hierarchy
of nodes. Some nodes may be branch nodes and have child nodes, while others are leaf nodes with no children.

Node Types:
There are different types of DOM nodes available in Apex. XmlNodeType is an enum of these different types. The values
are:
• COMMENT
• ELEMENT
• TEXT

It is important to distinguish between elements and nodes in an XML document. The following is a simple XML example:

<name>
<firstName>Suvain</firstName>
<lastName>Singh</lastName>
</name>

This example contains three XML elements: name, firstName, and lastName. It contains five nodes: the three name,
firstName, and lastName element nodes, as well as two text nodes—Suvain and Singh. Note that the text within an
element node is considered to be a separate text node.

Methods:

The XmlNode class has the following methods:

XmlNode Example:

This example shows how to use XmlNode methods and namespaces to create an XML request.

public class DomNamespaceSample
{
public void sendRequest(String endpoint)
{
// Create the request envelope
DOM.Document doc = new DOM.Document();
String soapNS = 'http://schemas.xmlsoap.org/soap/envelope/';
String xsi = 'http://www.w3.org/2001/XMLSchema-instance';
String serviceNS = 'http://www.myservice.com/services/MyService/';
dom.XmlNode envelope
= doc.createRootElement('Envelope', soapNS, 'soapenv');
envelope.setNamespace('xsi', xsi);
envelope.setAttributeNS('schemaLocation', soapNS, xsi, null);
dom.XmlNode body
= envelope.addChildElement('Body', soapNS, null);
body.addChildElement('echo', serviceNS, 'req').
addChildElement('category', serviceNS, null).
addTextNode('classifieds');
System.debug(doc.toXmlString());
// Send the request
HttpRequest req = new HttpRequest();
req.setMethod('POST');
req.setEndpoint(endpoint);
req.setHeader('Content-Type', 'text/xml');
req.setBodyDocument(doc);
Http http = new Http();
HttpResponse res = http.send(req);
System.assertEquals(200, res.getStatusCode());
dom.Document resDoc = res.getBodyDocument();
envelope = resDoc.getRootElement();
String wsa = 'http://schemas.xmlsoap.org/ws/2004/08/addressing';
dom.XmlNode header = envelope.getChildElement('Header', soapNS);
System.assert(header != null);
String messageId= header.getChildElement('MessageID', wsa).getText();

System.debug(messageId);
System.debug(resDoc.toXmlString());
System.debug(resDoc);
System.debug(header);
System.assertEquals(
'http://schemas.xmlsoap.org/ws/2004/08/addressing/role/anonymous',
header.getChildElement(
'ReplyTo', wsa).getChildElement('Address', wsa).getText());
System.assertEquals(
envelope.getChildElement('Body', soapNS).
getChildElement('echo', serviceNS).
getChildElement('something', 'http://something.else').
getChildElement(
'whatever', serviceNS).getAttribute('bb', null),
'cc');
System.assertEquals('classifieds',
envelope.getChildElement('Body', soapNS).
getChildElement('echo', serviceNS).
getChildElement('category', serviceNS).getText());
}
}