Can I validate an XML file using an external DTD

Question

Hi,
I'm trying to use an external DTD to validate an XML
file (which does not refer to this DTD). The java docs that ship
with the XML parser aren't clear on how exactly to do this (or
whether it can be done). I'd appreciate any advice on how I
should perform this operation.
Here's what I'm doing right now.
1) The Java file
import oracle.xml.parser.v2.*;
public class ParseWithExternalDTD
public static void main(String args[]) throws Exception
DOMParser dp=new DOMParser();
dp.parseDTD
("file:d:/jdk1.2/sample/test/family.DTD","family");
DTD dtd=dp.getDoctype();
dp.setDoctype(dtd);
dp.parse("file:d:/jdk1.2/sample/test/family.xml");
System.out.println("Finished with no errors!");
2) The family.DTD file
<!ELEMENT family (member*)>
<!ATTLIST family lastname CDATA #REQUIRED>
<!ELEMENT member (#PCDATA)>
<!ATTLIST member memberid ID #REQUIRED>
<!ATTLIST member dad IDREF #IMPLIED>
<!ATTLIST member mom IDREF #IMPLIED>
3) The family.xml file
<?xml version="1.0" standalone="no"?>
<family lastname="Smith">
<TagToFoilParserValidation>
</TagToFoilParserValidation>
<member memberid="m1">Sarah</member>
<member memberid="m2">Bob</member>
<member memberid="m3" mom="m1" dad="m2">Joanne</member>
<member memberid="m4" mom="m1" dad="m2">Jim</member>
</family>
4) The output
Finished with no errors!
As you can see, the DOMParser failed to validate the family.xml
file against the family dtd otherwise, it would have reported a
validation error when it came across the
TagToFoilParserValidation.
Any insight as to what I'm doing wrong would be much appreciated.
Sincerely,
Keki
Project Iona
Manufacturing Applications
Oracle Corporation
The views and opinions expressed here are
my own and do not reflect the views and
opinions of Oracle Corporation
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Answer 1

Keki Burjorjee (Oracle) (guest) wrote:
: 2 further questions related to this issue.
: 1) Say I am using XSLT to transform A.xml into B.xml, and I
: want to embed a reference to B.dtd within the B.xml file. Is
: there an XSLT command which will allow me to do this?
: 2) Is it possible for your team to give me a mechanism whereby
I
: can preset the xml parser to validate the next xml file (or
: inputstream) it receives against a particular DTD? This scheme
: does not require the dtd to be present within the XML file
: Thanks,
: - Keki
: Oracle XML Team wrote:
: : What you are doing wrong is not including a reference to the
: : applicable DTD in your XML document. Without it there is no
: way
: : that the parser knows what to validate against. Including
the
: : reference is the XML standard way of specifying an external
: : DTD. Otherwise you need to embed the DTD in your XML
Document.
: : Oracle XML Team
: : http://technet.oracle.com
: : Oracle Technology Network
: : Keki Burjorjee (guest) wrote:
: : : Hi,
: : : I'm trying to use an external DTD to validate an XML
: : : file (which does not refer to this DTD). The java docs that
: : ship
: : : with the XML parser aren't clear on how exactly to do this
: (or
: : : whether it can be done). I'd appreciate any advice on how I
: : : should perform this operation.
: : : Here's what I'm doing right now.
: : : 1) The Java file
: : : import oracle.xml.parser.v2.*;
: : : public class ParseWithExternalDTD
: : : public static void main(String args[]) throws Exception
: : : DOMParser dp=new DOMParser();
: : : dp.parseDTD
: : : ("file:d:/jdk1.2/sample/test/family.DTD","family");
: : : DTD dtd=dp.getDoctype();
: : : dp.setDoctype(dtd);
: : : dp.parse("file:d:/jdk1.2/sample/test/family.xml");
: : : System.out.println("Finished with no errors!");
: : : 2) The family.DTD file
: : : <!ELEMENT family (member*)>
: : : <!ATTLIST family lastname CDATA #REQUIRED>
: : : <!ELEMENT member (#PCDATA)>
: : : <!ATTLIST member memberid ID #REQUIRED>
: : : <!ATTLIST member dad IDREF #IMPLIED>
: : : <!ATTLIST member mom IDREF #IMPLIED>
: : : 3) The family.xml file
: : : <?xml version="1.0" standalone="no"?>
: : : <family lastname="Smith">
: : : <TagToFoilParserValidation>
: : : </TagToFoilParserValidation>
: : : <member memberid="m1">Sarah</member>
: : : <member memberid="m2">Bob</member>
: : : <member memberid="m3" mom="m1" dad="m2">Joanne</member>
: : : <member memberid="m4" mom="m1" dad="m2">Jim</member>
: : : </family>
: : : 4) The output
: : : Finished with no errors!
: : : As you can see, the DOMParser failed to validate the
: : family.xml
: : : file against the family dtd otherwise, it would have
: reported
: : a
: : : validation error when it came across the
: : : TagToFoilParserValidation.
: : : Any insight as to what I'm doing wrong would be much
: : appreciated.
: : : Sincerely,
: : : Keki
: : : Project Iona
: : : Manufacturing Applications
: : : Oracle Corporation
: : : The views and opinions expressed here are
: : : my own and do not reflect the views and
: : : opinions of Oracle Corporation
1) No XSLT commands exist that allow you to embed a DTD while
doing the transformation.
2) You can use the setDocType() method in the parser, to set a
DTD based on which the XML document will be validated. The
parseDTD() method allows you to parse a DTD file separately and
get a DTD object. Here is a sample code :
DOMParser domparser = new DOMParser();
domparser.setValidationMode(true);
// parse the DTD file
domparser.parseDTD(new FileReader(dtdfile));
DTD dtd = domparser.getDocType();
// Parse XML file - XML file will be validated based on the DTD.
domparser.setDocType(dtd);
domparser.parse(new FileReader(xmlfile));
Document doc = domparser.getDocument();
Oracle XML Team
http://technet.oracle.com
Oracle Technology Network
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