Question

I’m making a simple drawing program with slides in it and I have an XML file with the following schema:

For every slide, I store a line or multiple line segments such as:

http://orhancanceylan.com/stack/file.xml

I’m taking “Slides” with this code:

NodeList nodeLst = doc.getElementsByTagName("Slide");
System.out.println(nodeLst.getLength());

And iterate by taking nodes:

Node fstNode = nodeLst.item(i);

But in my iteration, I couldn’t figure out how I should take the line segment or lines only for the first node(first slide).

How should I parse these XML properly?

Thanks.

Answer 1

Perhaps you could consider using XPath to do the dirty work of looking up your XML nodes:

http://download.oracle.com/javase/6/docs/api/javax/xml/xpath/package-summary.html

To get just the segment from the first slide, the XPath could be: //Slide[id='0']/segment

For example, maybe something like this:

XPathFactory factory = XPathFactory.newInstance();
XPath xpath = factory.newXPath();
XPathExpression expr = xpath.compile("//Slide[id='0']/segment");

Then evaluate your doc with the given XPath expression, and typecast the resulte:

Object result = expr.evaluate(doc, XPathConstants.NODESET);
NodeList nodes = (NodeList) result;

That will give you just the first slide’s <segment> node in your XML. You can probably extrapolate from that answer on how to get more XML nodes using XPath. See http://www.ibm.com/developerworks/library/x-javaxpathapi/index.html