XSLT result type is extremely slow for actions that produce a large xml document

XSL transformations take what seems like an exponential increase in time with respect to the size of the xml document produced from the action. I ran our app through a profiler and determined almost all of the time was being spent in a couple of log statements in the following method from the class, org.apache.struts2.views.xslt.AbstractAdapterNode.

public Node getChildBeforeOrAfter(Node child, boolean before)

{ log.debug("getChildBeforeOrAfter: "); List adapters = getChildAdapters(); log.debug("childAdapters = " + adapters); log.debug("child = " + child); int index = adapters.indexOf(child); if (index < 0) throw new StrutsException(child + " is no child of " + this); int siblingIndex = before ? index - 1 : index + 1; return ((0 < siblingIndex) && (siblingIndex < adapters.size())) ? ((Node) adapters.get(siblingIndex)) : null; }

This method gets called very frequently while the transformer is traversing the document, multiple times for each node. Since there is not a guard around the debug statements, the toString method on the adapters and child variables is called even when not in debug mode. I added the guard if (log.isDebugEnabled()) around the two lines and the transformation only took about 4 seconds instead of 80+ seconds for our action which returned about 1000 users.

I created a patch and will attach it to this ticket. This is the first time that I have created a patch using subversion so let me know if I am missing something. It would be nice if this could be back ported to 2.0.X since we are using that branch for the time being.