[jdom-interest] builders not preserving namespace attributes in xsl files

[Brett McLaughlin]

Ed Morehouse wrote:
> 
> Brett McLaughlin wrote:
> >   I think I got attribute namespaces working correctly in Beta 5. At
> > least, I tested some documents with namespaces on just attributes (see
> > the contents.xml file in the samples directory of the JDOM core module),
> > and they worked. Now, mind you, this isn't declarations that aren't used
> > or multiple declarations on elements yet, as that is still in progress;
> > but attributes that have prefixes and namespaces should now be working.
> >
> > Let me know, OK?
> >
> > Thanks,
> > Brett
> --
> 
> Hi Brett,
> 
> I checked out the latest sources from CVS today and tried building the
> contents.xml file in the samples directory using both SAXBuilder and
> DOMBuilder.  In the case of SAXBuilder, it worked like a charm, but DOMBuilder
> choked on the following exception:

You're right, and I got it fixed, largely using your patch. Thanks ... I
always do SAXBuilder and forget about DOMBuilder ;-)

Works great now! Latest is in CVS.

-Brett

> 
> Exception in thread "main" org.jdom.JDOMException: The name "ora:category" is
> not legal for JDOM/XML attributes: Attribute names cannot contain colons.: The
> name "ora:category" is not legal for JDOM/XML attributes: Attribute names cannot
> contain colons.
>         at org.jdom.input.DOMBuilder.build(DOMBuilder.java:194)
>         at org.jdom.input.DOMBuilder.build(DOMBuilder.java:216)
>         at BugDemo.demoBug(BugDemo.java:41)
>         at BugDemo.main(BugDemo.java:19)
> Root cause: org.jdom.IllegalNameException: The name "ora:category" is not legal
> for JDOM/XML attributes: Attribute names cannot contain colons.
>         at org.jdom.Attribute.<init>(Attribute.java:107)
>         at org.jdom.Attribute.<init>(Attribute.java:151)
>         at org.jdom.Element.addAttribute(Element.java:1205)
>         at org.jdom.input.DOMBuilder.buildTree(DOMBuilder.java:358)
>         at org.jdom.input.DOMBuilder.buildTree(DOMBuilder.java:296)
>         at org.jdom.input.DOMBuilder.build(DOMBuilder.java:191)
>         at org.jdom.input.DOMBuilder.build(DOMBuilder.java:216)
>         at BugDemo.demoBug(BugDemo.java:41)
>         at BugDemo.main(BugDemo.java:19)
> 
> >From what i can tell, the trouble starts around line 358 of
> DOMBuilder.buildTree().  As an aside, the "if
> (!att.getNodeName().startsWith("xmlns:"))" statement on line 357 seems to be
> completely superfluous, since above in line 308, we are assured that namespace
> declarations don't get added to the elementAttribute list in the fist place.
> But anyway, line 358 causes an Attribute object to be constructed and added to
> the current Element object.  The problem seems to be that this is always done
> with the two argument constructor for Attribute, which expects a local name and
> a value, and thus assumes that the attribute is not associated with any
> namespace--even if it does have a namespace, indicated by the presence of a
> colon.  When this constructor calls the canonical, three argument constructor,
> the Verifier sees the colon and causes the constructor to throw an
> IllegalNameException (line 107 of Attribute.java).
> 
> The solution would seem to be that on line 357 of Dombuilder.java, in the
> buildTree() method, instead of checking whether the node name starts with
> "xmlns:", to check whether the node name contains a colon, and if so, to add the
> attribute to the element using a constructor for Attribute that accepts a
> namespace, which would be parsed from the namespace-enabled attribute name.
> Perhaps something like this:
> 
> (replaces DOMBuilder.java 356-360)
> /// begin patch
> 
>         // add the attributes:
>         if (att.getNodeName().indexOf(":") == -1)
>         {  // attribute is namespace-free:
>                 element.addAttribute(att.getNodeName(), att.getNodeValue());
>         }
>         else
>         {  // attribute has a namespace:
>                 String qualifiedAttributeName = att.getNodeName();
>                 int splitter = qualifiedAttributeName.indexOf(":");
>                 String prefix = qualifiedAttributeName.substring(0, splitter);
>                 String localName = qualifiedAttributeName.substring(splitter + 1);
>                 String uri = ((Namespace)prefixedNamespaces.get(prefix)).getURI();
>                 String value = att.getNodeValue();
>                 element.addAttribute(new Attribute(localname, prefix, uri, value));
>         }
> 
> /// end patch
> 
> and to finish things off, org.jdom.Attribute needs to be imported up at the top.
> 
> As far as i can see, that should work.  But, be warned, i am not a very active
> JDOM developer, so it is possible that i am missing something subtle.  Please
> let me know what you think.
> 
> -Ed
> 
> p.s.
> 
> If you would like to duplicate the behavior i have reported, you can run the
> following program on contents.xml:
> 
> /// begin source
> 
> import org.jdom.input.SAXBuilder;
> import org.jdom.input.DOMBuilder;
> import org.jdom.output.XMLOutputter;
> 
> import java.io.File;
> import java.io.InputStream;
> import java.io.OutputStream;
> import java.io.FileInputStream;
> 
> public class BugDemo
>         extends Object
> {
>         public static void main(String[] args)
>                 throws Exception
>         {
>                 if (args.length == 1)
>                 {
>                         File file = new File(args[0]);
>                         new BugDemo().demoBug(file);
>                 }
>                 else
>                 {
>                         System.out.println("useage: java BugDemo
> <XMLFileName>");
>                 }
>         }
> 
>         public void demoBug(File file)
>                 throws Exception
>         {
> 
> System.out.println("\n----------------------------------------\n");
>                 System.out.println("here's an XML file:");
> 
> System.out.println("\n----------------------------------------\n");
>                 copyStream(new FileInputStream(file), System.out);
> 
> System.out.println("\n----------------------------------------\n");
>                 System.out.println("here's the same file after the SAXBuilder
> has its way with it:");
> 
> System.out.println("\n----------------------------------------\n");
>                 new XMLOutputter().output(new SAXBuilder().build(file),
> System.out);
> 
> System.out.println("\n----------------------------------------\n");
>                 System.out.println("here's the same file after the DOMBuilder
> has its way with it:");
> 
> System.out.println("\n----------------------------------------\n");
>                 new XMLOutputter().output(new DOMBuilder().build(file),
> System.out);
> 
> System.out.println("\n----------------------------------------\n");
>                 System.out.println("notice that only the xmlns:xsl namespace is
> being preserved.");
>                 System.out.println("where did the rest of the namespace
> declarations go?");
> 
> System.out.println("\n----------------------------------------\n");
>         }
> 
>         private void copyStream(InputStream in, OutputStream out)
>                 throws Exception
>         {
>                 byte[] buffer = new byte[256];
>                 while (true)
>                 {
>                         int bytes = in.read(buffer);
>                         if (bytes == -1) break;
>                         out.write(buffer, 0, bytes);
>                 }
>         }
> 
> }
> /// end source
> 
>                                   ------------
> 
>  - The happiest of people aren't the ones
>    who always have the best of everything;
>    they are the ones who always make the best
>    of everything they have.
> 
>                                            Ed Morehouse
>                                            Software Engineer/Evil Genius
>                                            The Motley Fool

-- 
Brett McLaughlin, Enhydra Strategist
Lutris Technologies, Inc. 
1200 Pacific Avenue, Suite 300 
Santa Cruz, CA 95060 USA 
http://www.lutris.com
http://www.enhydra.org