XSD Tutorials - Herong's Tutorial Examples - Version 5.10, by Dr. Herong Yang

XML Schema (XSD) Validation using SAXParser

This section describes a tutorial example on how to the Xerces2 SAXParser class to validate an XML document assigned with an XSD file. The sample program SAXValidator.java works up to JDK 1.6. It is not working with JDK 1.7.

Xerces-J package can also be loaded by the SAXParserFactory.newInstance() method to do XSD schema validation. Here is my sample program SAXValidator.java:

/* SAXValidator.java
 - Copyright (c) 2013, HerongYang.com, All Rights Reserved.
 */
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.ParserConfigurationException;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;
class SAXValidator {
   public static void main(String[] args) {
      String schemaFeature 
         = "http://apache.org/xml/features/validation/schema";
      try {
         File x = new File(args[0]);
         SAXParserFactory f = SAXParserFactory.newInstance();
         System.out.println(f.toString());
         f.setValidating(true);
         f.setFeature(schemaFeature,true);
         SAXParser p = f.newSAXParser();
         System.out.println(p.toString());
         DefaultHandler h = new MyErrorHandler();
         p.parse(x,h);
      } catch (ParserConfigurationException e) {
         System.out.println(e.toString()); 
      } catch (SAXException e) {
         System.out.println(e.toString()); 
      } catch (IOException e) {
         System.out.println(e.toString()); 
      }
   }
   private static class MyErrorHandler extends DefaultHandler {
      public void warning(SAXParseException e) throws SAXException {
         System.out.println("Warning: "); 
         printInfo(e);
      }
      public void error(SAXParseException e) throws SAXException {
         System.out.println("Error: "); 
         printInfo(e);
      }
      public void fatalError(SAXParseException e) throws SAXException {
         System.out.println("Fattal error: "); 
         printInfo(e);
      }
      private void printInfo(SAXParseException e) {
         System.out.println("   Public ID: "+e.getPublicId());
         System.out.println("   System ID: "+e.getSystemId());
         System.out.println("   Line number: "+e.getLineNumber());
         System.out.println("   Column number: "+e.getColumnNumber());
         System.out.println("   Message: "+e.getMessage());
      }
   }
}

Note that the schema feature is set to the SAXParserFactory object, not to the SAXParser object.

Running SAXValidator.java with JDK 1.4 and Xerces-J 2.3 in 2002:

javac SAXValidator.java

java -cp . SAXValidator dictrionary_invalid_xsd.xml

org.apache.crimson.jaxp.SAXParserFactoryImpl@1004901
org.xml.sax.SAXNotRecognizedException: 
   Feature: http://apache.org/xml/features/validation/schema

Note that the default SAXParser in JDK 1.4 is the "crimson" implementation, doesn't support XSD validation.

We need to run SAXValidator.java with Xerces-J 2.3 JAR file specified:

java -cp ".;\local\xerces-2_3_0\xercesImpl.jar"
   SAXValidator dictrionary_invalid_xsd.xml

org.apache.xerces.jaxp.SAXParserFactoryImpl@f72617
org.apache.xerces.jaxp.SAXParserImpl@173831b

Error:
   Public ID: null
   System ID: file:///C:/herong/dictionary_invalid_xsd.xml
   Line number: 7
   Column number: 22
   Message: cvc-datatype-valid.1.2.1: 'yes' is not a valid value for 
   'boolean'.

...

Conclusion: my SAXValidator.java can be used with the "Xerces-J 2.3" implementation of SAXParser to validate XML documents with XSD schema.

Running SAXValidator.java with JDK 1.6 and Xerces2 2.9.1 in 2009: I am getting the same result as JDK 1.4 with Xerces-J 2.3.

Running SAXValidator.java with JDK 1.7 and Xerces2 2.11.0 in 2013:

c:\Progra~1\Java\jdk1.7.0_07\bin\javac XMLReaderValidator.java
   
c:\Progra~1\Java\jdk1.7.0_07\bin\java 
   SAXValidator dictionary_invalid_xsd.xml

com.sun.org.apache.xerces.internal.jaxp.SAXParserFactoryImpl@e86da0
com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl@17c2891
Error:
   Public ID: null
   System ID: file:/C:/herong/dictionary_invalid_xsd.xml
   Line number: 3
   Column number: 49
   Message: cvc-elt.1: Cannot find the declaration of element 'dictionary'.

Notice that the default SAXParser in JDK 1.7 is the "xerces" implementation. But it is not able to load the XSD document specified in the XML document as: xsi:noNamespaceSchemaLocation="dictionary.xsd"

See next tutorial on how to resolve this issue.

Last update: 2013.

Table of Contents

 About This Book

 Introduction to XML Schema

 XML Editor and Schema Processor - XMLPad

 Java API for XML Processing - JAXP

 JAXP - XML Schema (XSD) Validation

 Xerces2 Java Parser - Java API of XML Parsers

Using Xerces2 Java API

 XML Schema (XSD) Validation using XMLReader

 Running XMLReaderValidator with Xerces2 2.11.0 Beta

 Running XMLReaderValidator on XSD 1.1 Schema

XML Schema (XSD) Validation using SAXParser

 SAXParser for XSD Validation in JDK 1.7

 SAXParser for XSD 1.1 Validation

 Xsd11SchemaValidator.java for XSD 1.1 Validation

 Xsd11SchemaValidator.java XSD 1.1 Test Result

 XML Schema Language - Basics

 Introduction of XSD Built-in Datatypes

 "string" and Its Derived Datatypes

 "decimal" and Its Derived Datatypes

 "dateTime" and Its Related Datatypes

 Miscellaneous Built-in Datatypes

 Facets, Constraining Facets and Restriction Datatypes

 "simpleType" - Defining Your Own Simple Datatypes

 Complex Element Declaration

 Identity-Constraints: unique, key and keyref

 Assertion as Custom Validation Rules

 XML Schema Location and Namespace in XML Documents

 Overriding Element Types in XML Documents

 Linking Multiple Schema Documents Together

 Glossary

 References

 PDF Printing Version

XML Schema (XSD) Validation using SAXParser - Updated in 2014, by Dr. Herong Yang