@@ -7,13 +7,25 @@
*/
package org.apache.myrmidon.components.builder;
import javax.xml.transform.Transformer;
import java.net.URL;
import java.io.InputStream;
import java.util.Properties;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.apache.avalon.framework.configuration.SAXConfigurationHandler;
import org.apache.avalon.framework.parameters.Parameterizable;
import org.apache.avalon.framework.parameters.Parameters;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.sax.SAXSource;
import javax.xml.transform.sax.SAXTransformerFactory;
import javax.xml.transform.sax.TransformerHandler;
import javax.xml.transform.stream.StreamSource;
import org.apache.avalon.framework.configuration.SAXConfigurationHandler;
import org.apache.avalon.excalibur.io.FileUtil;
import javax.xml.transform.stream.StreamResult;
/**
* Default implementation to construct project from a build file.
@@ -22,24 +34,173 @@ import org.apache.avalon.excalibur.io.FileUtil;
*/
public class XSLProjectBuilder
extends DefaultProjectBuilder
implements Parameterizable
{
protected void process( final String sourceID,
private final static String PARAM_EXCEPTION =
"Malformed PI: expected <?xsl-param name=\"foo\" value=\"bar\"?>";
private final static String PARAMS_EXCEPTION =
"Malformed PI: expected <?xsl-params location=\"myparams.properties\"?>";
private final static String STYLE_EXCEPTION =
"Malformed PI: expected <?xsl-params href=\"mystylesheet.xsl\"?>";
private Parameters m_parameters;
private URL m_systemID;
public void parameterize( final Parameters parameters )
{
m_parameters = parameters;
}
protected void process( final URL sourceID,
final SAXConfigurationHandler handler )
throws Exception
{
final String xslSheet = FileUtil.removeExtension( sourceID ) + ".xsl";
final SAXParserFactory saxParserFactory = SAXParserFactory.newInstance();
final SAXParser saxParser = saxParserFactory.newSAXParser();
final XMLReader reader = saxParser.getXMLReader();
reader.setFeature( "http://xml.org/sax/features/validation", false );
reader.setErrorHandler( handler );
final ReactorPIHandler reactorHandler = new ReactorPIHandler();
reader.setContentHandler( reactorHandler );
try { reader.parse( sourceID.toString() ); }
catch( final StopParsingException spe )
{
//Ignore me
}
Transformer transformer = null;
final int size = reactorHandler.getPICount();
for( int i = 0; i < size; i++ )
{
final String target = reactorHandler.getTarget( i );
final String data = reactorHandler.getData( i );
if( target.equals( "xsl-param" ) ) handleParameter( data );
else if( target.equals( "xsl-params" ) ) handleParameters( data, sourceID );
else if( target.equals( "xsl-stylesheet" ) )
{
if( null != transformer )
{
throw new SAXException( "Build file can not contain " +
"two xsl-stylesheet PIs" );
}
final TransformerFactory factory = TransformerFactory.newInstance();
final String stylesheet = getStylesheet( data, sourceID );
transformer = factory.newTransformer( new StreamSource( stylesheet ) );
}
}
if( null == transformer )
{
reader.setContentHandler( handler );
reader.parse( sourceID.toString() );
}
else
{
final SAXResult result = new SAXResult( handler );
transformer.transform( new StreamSource( sourceID.toString() ), result );
}
}
private void handleParameter( final String data )
throws SAXException
{
int index = data.indexOf( '\"' );
if( -1 == index )
{
throw new SAXException( PARAM_EXCEPTION );
}
index = data.indexOf( '\"', index + 1 );
if( -1 == index )
{
throw new SAXException( PARAM_EXCEPTION );
}
// Create a transform factory instance.
final TransformerFactory factory = TransformerFactory.newInstance();
//split between two "attributes" occurs on index
final String[] name = parseAttribute( data.substring( 0, index + 1 ) );
final String[] value = parseAttribute( data.substring( index + 1 ).trim() );
if( !name[ 0 ].equals( "name" ) || !value[ 0 ].equals( "value" ) )
{
throw new SAXException( PARAM_EXCEPTION );
}
// Create a transformer for the stylesheet.
final Transformer transformer = factory.newTransformer( new StreamSource( xslSheet ) );
m_parameters.setParameter( name[ 1 ], value[ 1 ] );
}
final SAXResult result = new SAXResult( handler );
private void handleParameters( final String data, final URL baseSource )
throws SAXException
{
final String[] params = parseAttribute( data );
if( !params[ 0 ].equals( "location" ) )
{
throw new SAXException( PARAMS_EXCEPTION );
}
try
{
final Properties properties = new Properties();
final URL url = new URL( baseSource, params[ 1 ] );
final InputStream input = url.openStream();
properties.load( input );
final Parameters parameters = Parameters.fromProperties( properties );
m_parameters.merge( parameters );
}
catch( final Exception e )
{
throw new SAXException( "Error loading parameters: " + e );
}
}
private String getStylesheet( final String data, final URL baseSource )
throws SAXException
{
final String[] stylesheet = parseAttribute( data );
if( !stylesheet[ 0 ].equals( "href" ) )
{
throw new SAXException( STYLE_EXCEPTION );
}
try { return new URL( baseSource, stylesheet[ 1 ] ).toString(); }
catch( final Exception e )
{
throw new SAXException( "Error locating stylesheet '" + stylesheet[ 1 ] +
"' due to " + e );
}
}
private String[] parseAttribute( final String data )
throws SAXException
{
//name="value"
int index = data.indexOf( '=' );
if( -1 == index )
{
throw new SAXException( "Expecting an attribute but received '" +
data + "'" );
}
//Make a debug option for this
//transformer.transform( new StreamSource( sourceID ), new StreamResult( System.out ) );
final int size = data.length();
if( '\"' != data.charAt( index + 1 ) ||
'\"' != data.charAt( size - 1 ) ||
size - 1 == index )
{
throw new SAXException( "Expecting the value of attribute " +
data.substring( 0, index ) +
" to be enclosed in quotes" );
}
final String[] result = new String[ 2 ];
result[ 0 ] = data.substring( 0, index );
result[ 1 ] = data.substring( index + 2, size - 1 );
transformer.transform( new StreamSource( sourceID ), result );
return result ;
}
}
Peter Donald