Optional elements not supported in XML parser for java

Question

I am using v2 parser version 2.0.2.8.0 for java. Looks like this parser does not support optional elements.
My DTD looks like
<!ELEMENT Graph (Background, ImageSize)?>
<!ELEMENT ImageSize EMPTY>
<!ATTLIST ImageSize
width CDATA #IMPLIED
height CDATA #IMPLIED >
<!ELEMENT Background EMPTY>
<!ATTLIST Background
fillColor CDATA #IMPLIED>
If I set the XML following XML
<?xml version="1.0" ?>
<Graph>
<ImageSize width="422" height="477"/>
</Graph>
I am getting XMLParseException :Invalid element 'ImageSize' in content of 'Graph', expected elements '[Background]'
The parser expects all the elements to be present in the XML although the elements are defined as optional in the DTD. It used to work fine until v2 parser version 2.0.2.7.0. Is this a bug?
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Answer 1

The value of JAXP is that it allows one to
freely switch parsers without changing any code. I have an application that uses the JAXP interfaces to create my DOM parser. I am using the Xerces-J parser now. I wanted to try Oracle's parser to see how it compares. To my great surprise, I found the Oracle DOM parser doesn't support JAXP. Because of this I have to CHANGE my code to user the Oracle DOM parser. Thus defeating the purpose of coding my app to the JAXP interface.
I have to add that I am surprised to see that a developer of Oracle's XML parser has to even ask what the value of JAXP is. I would think that being a parser developer, you would know and understand the value of JAXP.
I would like to know why Oracle has chosen not to support JAXP? Or have you just not even thought about whether or not you should support it.
Thanks,
Keith Jensen
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Steven Muench ([email protected]):
What is the perceived value in implementing the JAXP standard? We already implement SAX, have plans for SAX2, and are working with other XSLT vendors on the TRAX api for XSLT processors.
If there is strong customer demand, we'll clearly consider it, but at the moment that has not been the case.<HR></BLOCKQUOTE>
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