code: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements. See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership. The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the  "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  /*
   * $Id$
   */
  import javax.xml.parsers.SAXParserFactory;
  import javax.xml.transform.Transformer;
  import javax.xml.transform.TransformerException;
  import javax.xml.transform.TransformerFactory;
  import javax.xml.transform.sax.SAXSource;
  import javax.xml.transform.stream.StreamResult;
  import javax.xml.transform.stream.StreamSource;
  
  import org.xml.sax.InputSource;
  import org.xml.sax.SAXException;
  import org.xml.sax.SAXParseException;
  import org.xml.sax.XMLReader;
  import org.xml.sax.helpers.DefaultHandler;
  
  /**
   * Validate the XML input by using SAXParserFactory to turn on namespace awareness and 
   * validation, and a SAX XMLReader to parse the input and report problems to an error 
   * handler.
   * 
   * This sample uses birds.xml with an internal DOCTYPE declaration. As shipped, birds.xml
   * contains an element that violates the declared document type.
   */
  public class ValidateXMLInput
  {
    
    public static void main(String[] args) 
      throws Exception
    {
      ValidateXMLInput v = new ValidateXMLInput();
      v.validate();
    }
  
    void validate()
      throws Exception
     {
       // Since we're going to use a SAX feature, the transformer must support 
      // input in the form of a SAXSource.
      TransformerFactory tfactory = TransformerFactory.newInstance();
      if(tfactory.getFeature(SAXSource.FEATURE))
      {
        // Standard way of creating an XMLReader in JAXP 1.1.
        SAXParserFactory pfactory= SAXParserFactory.newInstance();
        pfactory.setNamespaceAware(true); // Very important!
        // Turn on validation.
        pfactory.setValidating(true);
        // Get an XMLReader.
        XMLReader reader = pfactory.newSAXParser().getXMLReader();
    
        // Instantiate an error handler (see the Handler inner class below) that will report any
        // errors or warnings that occur as the XMLReader is parsing the XML input.
        Handler handler = new Handler();
        reader.setErrorHandler(handler);
    
        // Standard way of creating a transformer from a URL.
        Transformer t = tfactory.newTransformer(
          new StreamSource("birds.xsl"));
        
        // Specify a SAXSource that takes both an XMLReader and a URL.
        SAXSource source = new SAXSource(reader,
          new InputSource("birds.xml"));
        
        // Transform to a file.
        try
        {
          t.transform(source, new StreamResult("birds.out"));
        }
        catch (TransformerException te)
        {
          // The TransformerException wraps someting other than a SAXParseException
          // warning or error, either of which should be "caught" by the Handler.
          System.out.println("Not a SAXParseException warning or error: " + te.getMessage());
        }
                                    
        System.out.println("=====Done=====");
      }
      else
        System.out.println("tfactory does not support SAX features!");
    }
  
    // Catch any errors or warnings from the XMLReader.
    class Handler extends DefaultHandler
    {
      public void warning (SAXParseException spe)
  	     throws SAXException
      {
        System.out.println("SAXParseException warning: " + spe.getMessage());
      }    
  
      public void error (SAXParseException spe)
      	throws SAXException
      {
        System.out.println("SAXParseException error: " + spe.getMessage());
      }     
    }
  }
  