Android : how to access inner tag in XML using DOM Parsing Android?

I want to access the inner tag of an XML. Here is an XML I want to get URL From the Image tag.

<item>
    <title>`
    </title>

    <image>
            <url> any url here </url>
    </image>
<description>
</description>
<pubDate></pubDate>
</item>

here is the following code I am using please can you tell how to access url of image?

NodeList nl = doc.getElementsByTagName("item");
            int length = nl.getLength();

            for (int i = 0; i < length; i++) {
                Node currentNode = nl.item(i);
                RSSItem _item = new RSSItem();

                NodeList nchild = currentNode.getChildNodes();
                int clength = nchild.getLength();

                // Get the required elements from each Item
                for (int j = 0; j < clength; j = j + 1) {

                    Node thisNode = nchild.item(j);
                    String theString = null;
                    String nodeName = thisNode.getNodeName();

                    theString = nchild.item(j).getFirstChild().getNodeValue();

if (theString != null) {
                        if ("title".equals(nodeName)) {
                            // Node name is equals to 'title' so set the Node
                            // value to the Title in the RSSItem.
                            _item.setTitle(theString);
                        }

like I have set title I want to store the url in thestring and set image url. I need to retrieve this feed for my app that I am making.

Help would be appreciated. Thanks.