Validating

import org.xml.sax.*;
import org.xml.sax.helpers.*;
import java.io.*;


public class Validator {

  public static void main(String[] args) {

    XMLReader parser = XMLReaderFactory.createXMLReader();

    // turn on validation
    try {
      parser.setFeature(
       "http://xml.org/sax/features/validation", true);
      parser.setErrorHandler(new ValidityErrorReporter());
    }
    catch (SAXNotRecognizedException e) {
      System.err.println(
       "Installed XML parser cannot validate;"
       + " checking for well-formedness instead...");
    }
    catch (SAXNotSupportedException e) {
      System.err.println(
       "Cannot turn on validation here; "
       + "checking for well-formedness instead...");
    }

    if (args.length == 0) {
      System.out.println("Usage: java Validator URL1 URL2...");
    }

    // start parsing...
    for (int i = 0; i < args.length; i++) {

      // command line should offer URIs or file names
      try {
        parser.parse(args[i]);
        // If there are no well-formedness errors,
        // then no exception is thrown
        System.out.println(args[i] + " is well formed.");
      }
      catch (SAXParseException e) { // well-formedness error
        System.out.println(args[i] + " is not well formed.");
        System.out.println(e.getMessage()
         + " at line " + e.getLineNumber()
         + ", column " + e.getColumnNumber());
      }
      catch (SAXException e) { // some other kind of error
        System.out.println(e.getMessage());
      }
      catch (IOException e) {
        System.out.println("Could not check " + args[i]
         + " because of the IOException " + e);
      }

    }

  }

}