public void testGetNamespaceURI() {
// <e2 xmlns="http://www.blankns.com" ><e2child>I've no attributes</e2child></e2>
OMElement e2 = dp.omDocEle.getFirstChildWithName(new QName("http://www.blankns.com", "e2"));
// get the wrapped element
Element e = (Element) dp.fac.getNode(e2);
assertEquals("http://www.blankns.com", e.getNamespaceURI());
// <e2child>I've no attributes</e2child>
e = (Element) e.getFirstChild();
// e2child inherits the default namespace of e2
assertEquals("http://www.blankns.com", e.getNamespaceURI());
// <e3 name = "elem3" id="elem3"/>
OMElement e3 = dp.omDocEle.getFirstChildWithName(new QName("e3"));
// get the wrapped element
e = (Element) dp.fac.getNode(e3);
assertNull("Namespace URI of e3 is null", e.getNamespaceURI());
}