package com.mindprod.example;
import org.w3c.dom.Document;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import java.io.File;
import java.io.IOException;
import static java.lang.System.*;
/**
* Validate the syntax of an XML document.
*
* @author Roedy Green, Canadian Mind Products
* @version 1.0 2007-07-30
* @since 2007-07-30
*/
@SuppressWarnings( { "UnusedAssignment" } )
public final class TestXMLDTDValidator
{
/**
* Validate the syntax of an XML document that contains a DOCTYPE DTD to define the structure. XML docs to validate
* must start something like this:
* <p/>
* <?xml version="1.0" encoding="UTF-8"?>
* <p/>
* <!DOCTYPE web-app PUBLIC '-//Sun Microsystems, Inc.//DTD Web Application 2.2//EN'
* 'http://java.sun.com/j2ee/dtds/web-app_2_2.dtd'<
*
* @param args arg[0] is name of XML file.
*/
public static void main( String[] args )
{
try
{
final String filename = args[ 0 ];
out.println( "Parsing XML document: " + filename );
final DocumentBuilderFactory dbf =
DocumentBuilderFactory.newInstance();
dbf.setValidating( true );
final DocumentBuilder db = dbf.newDocumentBuilder();
db.setErrorHandler( new SimpleErrorHandler() );
final Document doc = db.parse( new File( filename ) );
}
catch ( IOException e )
{
err.println();
err.println( e.getMessage() );
err.println( "trouble opening file: " + args[ 0 ] );
err.println();
}
catch ( ParserConfigurationException e )
{
err.println();
err.println( e.getMessage() );
err.println( "Parser configuration problem" );
err.println();
}
catch ( SAXException e )
{
err.println();
err.println( e.getMessage() );
err.println( "Syntax error in XML file" );
err.println();
}
out.println( "done" );
}
}
/**
* handles errors discovered in the XML syntax
*/
final class SimpleErrorHandler implements ErrorHandler
{
/**
* default constructor
*/
public SimpleErrorHandler()
{
}
/**
* Receive notification of a recoverable error.
* <p/>
* This corresponds to the definition of "error" in section 1.2 of the W3C
* XML 1.0 Recommendation. For example, a validating parser would use this
* callback to report the violation of a validity constraint. The default
* behaviour is to take no action.
* <p/>
* <p/>
* <p/>
* The SAX parser must continue to provide normal parsing events after
* invoking this method: it should still be possible for the application to
* process the document through to the end. If the application cannot do so,
* then the parser should report a fatal error even if the XML recommendation
* does not require it to do so.
* <p/>
* Filters may use this method to report other, non-XML errors as well.
*
* @param exception The error information encapsulated in a SAX parse exception.
*
* @throws org.xml.sax.SAXException Any SAX exception, possibly wrapping another exception.
* @see org.xml.sax.SAXParseException
*/
public void error( SAXParseException exception ) throws SAXException
{
err.println( "error: " + exception );
}
/**
* Receive notification of a non-recoverable error. <p/> <p><strong>There is an apparent contradiction between the
* documentation for this method and the documentation for {@link org.xml.sax.ContentHandler#endDocument}. Until
* this ambiguity is resolved in a future major release, clients should make no assumptions about whether
* endDocument() will or will not be invoked when the parser has reported a fatalError() or thrown an
* exception.</strong></p> <p/> <p>This corresponds to the definition of "fatal error" in section 1.2 of the W3C XML
* 1.0 Recommendation. For example, a parser would use this callback to report the violation of a well-formedness
* constraint.</p> <p/> <p>The application must assume that the document is unusable after the parser has invoked
* this method, and should continue (if at all) only for the sake of collecting additional error messages: in fact,
* SAX parsers are free to stop reporting any other events once this method has been invoked.</p>
*
* @param exception The error information encapsulated in a SAX parse exception.
*
* @throws org.xml.sax.SAXException Any SAX exception, possibly wrapping another exception.
* @see org.xml.sax.SAXParseException
*/
public void fatalError( SAXParseException exception ) throws SAXException
{
err.println( "fatal: " + exception );
}
/**
* Receive notification of a warning. <p/> <p>SAX parsers will use this method to report conditions that are not
* errors or fatal errors as defined by the XML recommendation. The default behaviour is to take no action.</p>
* <p/> <p>The SAX parser must continue to provide normal parsing events after invoking this method: it should still
* be possible for the application to process the document through to the end.</p> <p/> <p>Filters may use this
* method to report other, non-XML warnings as well.</p>
*
* @param exception The warning information encapsulated in a SAX parse exception.
*
* @throws org.xml.sax.SAXException Any SAX exception, possibly wrapping another exception.
* @see org.xml.sax.SAXParseException
*/
public void warning( SAXParseException exception ) throws SAXException
{
err.println( "warning: " + exception );
}
}