Using this XML example:
<A>
<B>
<id>0</id>
</B>
<B>
<id>1</id>
</B>
</A>
I want a simple method to extract the XML block of node B, returning the XML String:
<B>
<id>1</id>
</B>
To retrieve this node i should use some Java XPath library like XOM or Java XPath, but i couldn't find how to get the complete XML string.
I found two equivalent answered questions using C#: C# How to extract complete xml node set and how can I extract an XML block from an XML document?
Adding to lwburk's solution, to convert a DOM Node to string form, you can use a Transformer:
private static String nodeToString(Node node)
throws TransformerException
{
StringWriter buf = new StringWriter();
Transformer xform = TransformerFactory.newInstance().newTransformer();
xform.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
xform.transform(new DOMSource(node), new StreamResult(buf));
return(buf.toString());
}
Complete example:
public static void main(String... args)
throws Exception
{
String xml = "<A><B><id>0</id></B><B><id>1</id></B></A>";
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
Document doc = dbf.newDocumentBuilder().parse(new InputSource(new StringReader(xml)));
XPath xPath = XPathFactory.newInstance().newXPath();
Node result = (Node)xPath.evaluate("A/B[id = '1']", doc, XPathConstants.NODE);
System.out.println(nodeToString(result));
}
private static String nodeToString(Node node)
throws TransformerException
{
StringWriter buf = new StringWriter();
Transformer xform = TransformerFactory.newInstance().newTransformer();
xform.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
xform.transform(new DOMSource(node), new StreamResult(buf));
return(buf.toString());
}