Deleting the children from node - xml

[Sathish Kumar Subramanian]

Hi

I want to remove total list of children from the node selected.


Here is the xml which I use,

<Diagram id="abc"> <Child1 id="1" name="Child1"/> <Child2 id="2" name="Child2"/> <Child3 id="3" name="Child3"/> </Diagram>


When selecting the diagram id 'abc', all the children inside the <Diagram> </Diagram> tag must be deleted, and also the Diagram tag.

Here the code i used,

		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
		DocumentBuilder docBuilder = null;
		try {
			docBuilder = factory.newDocumentBuilder();
		} catch (ParserConfigurationException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		Document doc = null;
		try {
			doc = (Document) docBuilder.parse(new File(propXmlFile));
		} catch (SAXException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		System.out.println("starting parser");
		 NodeList list = 
		 ((org.w3c.dom.Document) doc).getElementsByTagName("Diagram");
//		String xpath = "//Diagram";
//		List<NodeList> nodes = (List<NodeList>) XmlUtil.getElements(document,
//				xpath);

		for (int i = 0; i < ((NodeList) list).getLength(); i++) {
			// Get Node
			Node node = (Node) ((NodeList) list).item(i);
						
				NodeList childList = node.getChildNodes();
				// Look through all the children
				for (int x = 0; x < childList.getLength(); x++) {
					Node child = (Node) childList.item(x);

					node.getParentNode().removeChild(child);
			
			}
		}
	

[Paul Clapham]

You have this list: (0=child1, 1=child2, 2=child3). The first time through the loop you delete entry number 0, so now you have (0=child2, 1=child3). Then you delete entry number 1, so now you have (0=child2). Finally you delete entry number 2, which doesn't exist, so you still have (0=child2).

Either you should delete the entries in reverse order (2, then 1, then 0) or you should delete entry number 0 every time through the loop.

This is a classic gotcha of programming languages, nothing to do with XML at all, and people have been getting tricked by it for over 40 years now. You aren't the first.