XSD Tutorials - Herong's Tutorial Examples - v5.23, by Herong Yang
XSD Schema XML Validator - Final Version
This section describes the final version of the XML Schema (XSD) validator using the JAXP API.
The last XML Schema (XSD) validator, XsdSchemaSaxValidatorWithErrorHandler.java, needs one more enhancement to make to more user friendly. The error message needs to be printed out with the location where the error was detected. Here is the final version of my XML Schema validator using JAXP API, XsdSchemaValidator.java:
/* XsdSchemaValidator.java - Copyright (c) 2002-2013 HerongYang.com. All Rights Reserved. */ import javax.xml.validation.SchemaFactory; import javax.xml.validation.Schema; import javax.xml.XMLConstants; import javax.xml.transform.sax.SAXSource; import org.xml.sax.InputSource; import javax.xml.validation.Validator; import java.io.*; import org.xml.sax.SAXException; import org.xml.sax.SAXParseException; import org.xml.sax.ErrorHandler; class XsdSchemaValidator { private static int errorCount = 0; public static void main(String[] a) { if (a.length<2) { System.out.println("Usage:"); System.out.println("java XsdSchemaValidator schema_file_name " + "xml_file_name"); } else { String schemaName = a[0]; String xmlName = a[1]; Schema schema = loadSchema(schemaName); validateXml(schema, xmlName); } } public static void validateXml(Schema schema, String xmlName) { try { // creating a Validator instance Validator validator = schema.newValidator(); // setting my own error handler validator.setErrorHandler(new MyErrorHandler()); // preparing the XML file as a SAX source SAXSource source = new SAXSource( new InputSource(new java.io.FileInputStream(xmlName))); // validating the SAX source against the schema validator.validate(source); System.out.println(); if (errorCount>0) { System.out.println("Failed with errors: "+errorCount); } else { System.out.println("Passed."); } } catch (Exception e) { // catching all validation exceptions System.out.println(); System.out.println(e.toString()); } } public static Schema loadSchema(String name) { Schema schema = null; try { String language = XMLConstants.W3C_XML_SCHEMA_NS_URI; SchemaFactory factory = SchemaFactory.newInstance(language); schema = factory.newSchema(new File(name)); } catch (Exception e) { System.out.println(e.toString()); } return schema; } private static class MyErrorHandler implements ErrorHandler { public void warning(SAXParseException e) throws SAXException { System.out.println("Warning: "); printException(e); } public void error(SAXParseException e) throws SAXException { System.out.println("Error: "); printException(e); } public void fatalError(SAXParseException e) throws SAXException { System.out.println("Fattal error: "); printException(e); } private void printException(SAXParseException e) { errorCount++; System.out.println(" Line number: "+e.getLineNumber()); System.out.println(" Column number: "+e.getColumnNumber()); System.out.println(" Message: "+e.getMessage()); System.out.println(); } } }
Now try this final version on the XML file, first_html_extra_attribute.xml and the XSD file, first_html.xsd:
herong> javac XsdSchemaValidator.java herong> java XsdSchemaValidator first_html.xsd first_html_extra_attribute.xml Error: Line number: 3 Column number: 25 Message: cvc-type.3.1.1: Element 'body' is a simple type, so it cannot have attributes, excepting those whose namespace name is identical to 'http://www.w3.org/2001/XMLSchema-instance' and whose [local name] is one of 'type', 'nil', 'schemaLocation' or 'noNamespaceSchemaLocation'. However, the attribute, 'bgcolor' was found. Error: Line number: 5 Column number: 8 Message: cvc-type.3.1.2: Element 'body' is a simple type, so it must have no element information item [children]. Failed with errors: 2
Okay. I have a really good XML Schema processor based on JAXP API now.
Table of Contents
XML Editor and Schema Processor - XMLPad
Java API for XML Processing - JAXP
►JAXP - XML Schema (XSD) Validation
Standard Steps to Validate XML Documents Against a Schema
XSD Schema File Loader - XsdSchemaLoader.java
XSD Schema File Loading Errors
XSD Schema XML DOM Validator - XsdSchemaDomValidator.java
XSD Schema XML DOM Validation Errors
XSD Schema XML DOM Validator with Error Handler
XSD Schema XML SAX Validator - XsdSchemaSaxValidator.java
XSD Schema XML SAX Validation Errors
XSD Schema XML SAX Validator with Error Handler
►XSD Schema XML Validator - Final Version
XSD 1.1 Not Supported in JDK 13
Xerces2 Java Parser - Java API of XML Parsers
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
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