Where can I find a Java implementation of an ISO Schematron validator?

Question

The ISO Schematron standard has been out for two years now, but I'm still unable to find a Java implementation using ISO Schematron XSLT files (as opposed to files from an older version of Schematron, e.g. here: http://uploading.com/files/c9c9cb87/SchematronXpath.jar/).

Does anyone know of a production-ready ISO schema validator that can be easily called from a Java method?

Answer 1

Additionally you may use ph-schematron which provides both support for conversion to XSLT as well as a native plain Java validation, which is quicker than the XSLT version in nearly all cases. See https://github.com/phax/ph-schematron/ for the details as well as a quick intro. Example code to check if an XML file matches a Schematron file:

public static boolean validateXMLViaPureSchematron (File aSchematronFile, File aXMLFile) throws Exception { 
  final ISchematronResource aResPure = SchematronResourcePure.fromFile (aSchematronFile);
  if (!aResPure.isValidSchematron ()) 
    throw new IllegalArgumentException ("Invalid Schematron!"); 
  return aResPure.getSchematronValidity(new StreamSource(aXMLFile)).isValid ();
}

Answer 2

Probatron4j can validate against ISO Schematron. The website provides a single, self-contained JAR that's designed to be run from the command line, but it's easy to call Probatron from a Java method if you have its source code. Here's a simplified version of how I did it:

public boolean validateSchematron(InputStream xmlDoc, File schematronSchema) {
    // Session = org.probatron.Session; think of it as the Main class
    Session theSession = new Session();
    theSession.setSchemaSysId(schematronSchema.getName());
    theSession.setFsContextDir(schematronSchema.getAbsolutePath());

    // ValidationReport = org.probatron.ValidationReport; the output class
    ValidationReport validationReport = null;
    try
    {
        validationReport = theSession.doValidation(xmlDoc);
    }
    catch(Exception e) { /* ignoring to keep this answer short */ }

    if (validationReport == null ||
        !validationReport.documentPassedValidation()) {
        return false;
    }
    return true;
}

You'll need to make a few minor modifications to let Probatron know it's not being run from within a JAR file, but it doesn't take long.