Question

this is my first time using StAX for parsing XML documents (still in the learning stage). During the process to parse an XML document using XMLStreamReader and generate a copy of the document using XMLStreamWriter, I encountered the following warning represented as a comment in the output of the writer:

 <!-- Exception scanning External DTD Subset.  True contents of DTD cannot be determined.  Processing will continue as XMLInputFactory.IS_VALIDATING == false. -->

I understood the cause of the warning, but I wanted it to become an error rather than silently became a warning, so then I tried to set XMLInputFactory.IS_VALIDATING to true:

 XMLInputFactory factory = XMLInputFactory.newInstance();
 factory.setProperty(XMLInputFactory.IS_VALIDATING, Boolean.TRUE);

But the above threw an exception for me:

Exception in thread “main”
java.lang.IllegalArgumentException:
true value of isValidating not
supported at
com.sun.org.apache.xerces.internal.impl.PropertyManager.setProperty(PropertyManager.java:150)
at
com.sun.xml.internal.stream.XMLInputFactoryImpl.setProperty(XMLInputFactoryImpl.java:257)
at
com.test.test2.helper.SgmlDocumentParser.parse(SgmlDocumentParser.java:83)
at
com.test.test2.helper.Test.main(Test.java:66)

So what is wrong with my approach?

Thanks!

Answer 1

It looks like Sun’s StAX implementation just doesn’t support DTD validation. You could try using Woodstox instead, it appears to support validation.