/**
* Search specific element by key and tagName.
*
* @param root root element
* @param key search keyword
* @param tagName search tag name
* @return search result, null of either input is invalid or the looking result is not found.
*/
private Element searchForKey(final Element root, final String key, final String tagName) {
if (root == null || StringUtils.isEmptyString(key)) {
return null;
}
final Queue<Element> queue = new LinkedList<>();
queue.offer(root);
while (!queue.isEmpty()) {
final Element pe = queue.poll();
final NodeList pchildrenList = pe.getChildNodes();
for (int i = 0; i < pchildrenList.getLength(); i++) {
final Node node = pchildrenList.item(i);
if (node.getNodeType() == Node.ELEMENT_NODE) {
queue.offer((Element) node);
}
}
String value = pe.getNodeName();
if (StringUtils.isEmptyString(value) || !value.equals(tagName)) {
continue;
}
value = pe.getAttribute(ATTRIBUTE_NAME_NAME);
if (StringUtils.isEmptyString(value)) {
continue;
}
if (value.equals(key)) {
return pe;
}
}
return null;
}
