Hi Ovidue. I have put this on my to-do list with high priority, and will
try and integrate this weekend.
-scott
Ovidiu
Predescu To: [EMAIL PROTECTED], Gary L Peskin
<[EMAIL PROTECTED]>, Costin
<[EMAIL PROTECTED] Manolache <[EMAIL PROTECTED]>
p.com> cc: [EMAIL PROTECTED]
Sent by: Subject: [DTM] [PATCH] file, line, column
number information for XML
ovidiu@orion. source document
rgv.hp.com
06/27/01
07:13 PM
Hi Scott,
Thanks for the clarification on DTMDocumentImpl and DTMBuilder, with
this in mind I was able to focus my attention on the SAX2DTM
implementation.
The following patch is a rework of a previous patch I've submitted on
May 24 against the Stree model, current at that time. This time the
patch is against the DTM model, and makes use of DTM features to
optimize the lookup time and storage requirements. I hope this time
the patch gets incorporated in the CVS repository, before any major
rework happens again ;-).
As with the previous patch, there is no overhead in space or time if
source information is not needed.
>From a user perspective, this feature can be turned on by passing the
-L flag to Xalan when invoking it from the command
line. Programmatically you can also enable it by invoking the
setProperty method on the TransformerImpl:
TransformerImpl impl = ((TransformerImpl) transformer);
impl.setProperty(org.apache.xalan.transformer.XalanProperties.SOURCE_LOCATION,
Boolean.TRUE);
A Transformer "property" is different from a "feature": while a
feature is specific to all the transformer instances and usually
refers to an implementation aspect, a property is a runtime capability
that is set per Transformer instance. Currently the only property
added by this patch is the source location in the XML source document.
The patch adds two methods to the DTM interface:
public void setProperty(String property, Object value);
public SourceLocator getSourceLocatorFor(int node);
The second method is used to obtain the source location given a node
handle.
There are two ways you can make use of the source location. The first
one is from within a stylesheet, where you can have something like
this:
<xsl:stylesheet
xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
xmlns:nodeinfo="xalan://org.apache.xalan.lib.NodeInfo"
version="1.0">
<xsl:template match="*">
//node <xsl:value-of select="name()"/>
//file <xsl:value-of select="nodeinfo:systemId()"/>
//line <xsl:value-of select="nodeinfo:lineNumber()"/>
//column <xsl:value-of select="nodeinfo:columnNumber()"/>
<xsl:apply-templates/>
</xsl:template>
</xsl:stylesheet>
If no arguments are passed to the systemId(), lineNumber() or
columnNumber() functions, the corresponding information of the current
context node is returned. A node can be passed as argument to the
above functions, in which case the corresponding information about
that node is returned. If a node set containing multiple nodes is
passed as argument, only the information of the first node in the set
is returned.
The second way of obtaining the source location is
programmatically. Given a Node instance, one can obtain the owner DTM
and the node handle (an integer) that represents the
node. Unfortunately I didn't see any way of hiding this: if you find
one please let me know and I'll fix it.
The following example is extracted from PrintTraceListener and
illustrates the API:
Node sourceNode = ev.m_sourceNode;
int nodeHandler = ((DTMNodeProxy)sourceNode).getDTMNodeNumber();
SourceLocator locator = ((DTMNodeProxy)sourceNode).getDTM()
.getSourceLocatorFor(nodeHandler);
m_pw.println("Selected source node '" + sourceNode.getNodeName()
+ "', at " + locator);
There are two patches attached. The first contains the changes to the
Xalan2J source code relative to the CVS source code as of today. The
second patch contains an XML and an XSL stylesheet test files, which
are placed in the test/ directory.
Please let me know if you have any issues with the patch.
Best regards,
--
Ovidiu Predescu <[EMAIL PROTECTED]>
http://orion.nsr.hp.com/ (inside HP's firewall only)
http://www.geocities.com/SiliconValley/Monitor/7464/ (GNU, Emacs, other
stuff)
