Vikram A K Gupta wrote:
Hi All,
Background
- We are developing a generic cross reference task for a middleware application.
- We will be processing multiple XML formats and the plan is to have a single
instance of the new cross reference task.
- We plan on configuring XPATH rules to extract a value (extraction is
processed by another task and is complete)
- After obtaining the value from the XML, we will do a cross reference look-up
via a database and then look to repopulate the new value back in the msg via
the original XPATH rule,
The issue we are having is around the re-insertion of the value.
Approach that we are using:
1) XercesLiaisonParser to parse message
2) XPathEvaluator to identify a particular node
3) XalanNode::setNodeValue to modify the value
But we are getting 'Unknown exception' when i try to do
XalanNode::setNodeValue. Any pointers to resolve it ?
Following is code snippet but it is failing with the UNKNOWN EXCEPTION
It should not an "unknown" exception, it should be a XalanDOMException.
Here's a snippet from the source code:
void
XalanSourceTreeElement::setNodeValue(const XalanDOMString& /*
nodeValue */)
{
throw XalanDOMException(XalanDOMException::NO_MODIFICATION_ALLOWED_ERR);
}
Any clue how to resolve it and also an alternative approach to achieve the
requirement !!
try{
// We'll use these to parse the XML file.
XercesDOMSupport theDOMSupport;
XercesParserLiaison theLiaison(theDOMSupport);
// Create an input source...
const MemBufInputSource theInputSource( reinterpret_cast<const
XMLByte*>(message.c_str()),
XalanDOMString::length(message.c_str()),
"SourceXML",
false );
// Parse the XML Stream
XalanDocument* const theDocument =
theLiaison.parseXMLStream(theInputSource);
XPathEvaluator theEvaluator;
XalanNode* const theContextNode = theDocument->getDocumentElement();
//Retrieve the XalanNode for the compiled XPath
XalanNode* pXalanNode, *pConstNode = NULL;
pConstNode = theEvaluator.selectSingleNode (theDOMSupport,
theContextNode,
*m_compiledXPATH);
XalanDOMString xalanDOMString("NewValue");
pConstNode->setNodeValue(xalanDOMString); // UNKNOWN EXCEPTION BEING
THROWN
}
catch(const XalanDOMException& xde)
{
}
catch(const DOMException& de)
{
}
catch (...) // UNKNOWN EXCEPTION BEING CAUGHT HERE
{
}
Unless the node is a null pointer, and you're not checking for that, I
don't know why you're getting an unknown exception. Often, running your
code in a debugger will help with determining what's wrong.
However, your approach will not work, as the Xalan-C source tree is not
mutable. The typical way to handle this is to either use the Xerces-C
source tree with the Xalan-C wrappers, or write an XSLT stylesheet that
does the transformation, changing the values as appropriate.
Dave
---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
