Issue with XML child nodes iteration when mix of text and element nodes

I was trying to parse following strings to form a xml document and then trying to extract all child nodes of and add to a different document object which is already available to me.

<dhruba><test>this</test>that<test2>wang chu</test2> something.... </dhruba>

<dhruba>this is text node <test>this</test>that<test2>wang chu</test2> anything..</dhruba>

while I am trying to read the child nodes, it is returning null child for TEXT_NODE for 1st string and null for ELEMENT_NODE for 2nd String, this is wrong, is it API problem ??

I am using following code … it compile , I am using java 6.

        Node n = null;
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
                try {
                    db = dbf.newDocumentBuilder();
                } catch (ParserConfigurationException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
                dom = db.newDocument();
                Element rootEle = dom.createElement("resources");
        // adding the root element to the document
        dom.appendChild(rootEle);

        Element element = dom.createElement("string");

        element.setAttribute("name", "some_name");
        try {

            n = db.parse(new InputSource(new StringReader("<dhruba><test>this</test>that<test2>node value</test2> some text</dhruba>"))).getDocumentElement();
            n = dom.importNode(n, true);


            NodeList nodeList = n.getChildNodes();
            int length = nodeList.getLength();
            System.out.println("Total no of childs : "+length);
            for(int count = 0 ; count < length ; count++ ){
                Node node = nodeList.item(count);
                if(node != null ){
                    element.appendChild(node);
                }
            }
        } catch (SAXException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        rootEle.appendChild(element);

INPUT :: as string

             <dhruba><string name="some_name">
                        that
                        <test>this</test>                             
                        <test2>node   value</test2>
                        some text
                     </string>
              </dhruba>

EXPECTED OUTPUT :: as document

               <string>
                 <string name="some_name">
                            <test>this</test>
                             <test2>node   value</test2>
                 </string>
              </string>

if I try to parse

          <test>this</test>that<test2>wang chu</test2> something.... 

then output comes as “thiswang chu”

Why is this happening?  what needs to be done if I want to add following node under another document element, i.e. <string>.
    <test>this</test>
                        that                             
                        <test2>node   value</test2>
                        some text 
[notice that it does not have <dhruba>] inside parent node of another 
document.

Hope I am clear. Above code compiles in Java 6

Answer

Probably you want Node.cloneNode() method:

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();

Document dom = db.newDocument();

Element element = dom.createElement("string");
element.setAttribute("name", "some_name");

String inputXMLString = 
    "<dhruba><test>this</test>that<test2>node value</test2> some text</dhruba>";
Node n = db.parse(new InputSource(new StringReader(inputXMLString))).getDocumentElement();
n = dom.importNode(n, true);

NodeList nodeList = n.getChildNodes();
for (int i = 0; i < nodeList.getLength(); ++i)
{
    Node node = nodeList.item(i);
    element.appendChild(node.cloneNode(true));
}
dom.appendChild(element);

To get dom into stdout or file you could write:

TransformerFactory tFactory = TransformerFactory.newInstance();
Transformer transformer = tFactory.newTransformer();
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
DOMSource source = new DOMSource(dom);
StreamResult result = new StreamResult(System.out);
transformer.transform(source, result); 

Result:

<string name="some_name">
<test>this</test>that<test2>node value</test2> some text</string>

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