* This utility class is useful to combine JAXB with * other Java/XML technologies. * *
* The following example shows how to use JAXB to marshal a document * for transformation by XSLT. * *
*
* MyObject o = // get JAXB content tree
*
* // jaxbContext is a JAXBContext object from which 'o' is created.
* JAXBSource source = new JAXBSource( jaxbContext, o );
*
* // set up XSLT transformation
* TransformerFactory tf = TransformerFactory.newInstance();
* Transformer t = tf.newTransformer(new StreamSource("test.xsl"));
*
* // run transformation
* t.transform(source,new StreamResult(System.out));
*
*
*
* * The fact that JAXBSource derives from SAXSource is an implementation * detail. Thus in general applications are strongly discouraged from * accessing methods defined on SAXSource. In particular, * the setXMLReader and setInputSource methods shall never be called. * The XMLReader object obtained by the getXMLReader method shall * be used only for parsing the InputSource object returned by * the getInputSource method. * *
* Similarly the InputSource object obtained by the getInputSource
* method shall be used only for being parsed by the XMLReader object
* returned by the getXMLReader.
*
* @author
* Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)
*/
public class JAXBSource extends SAXSource {
/**
* Creates a new {@link javax.xml.transform.Source} for the given content object.
*
* @param context
* JAXBContext that was used to create
* contentObject. This context is used
* to create a new instance of marshaller and must not be null.
* @param contentObject
* An instance of a JAXB-generated class, which will be
* used as a {@link javax.xml.transform.Source} (by marshalling it into XML). It must
* not be null.
* @throws JAXBException if an error is encountered while creating the
* JAXBSource or if either of the parameters are null.
*/
public JAXBSource( JAXBContext context, Object contentObject )
throws JAXBException {
this(
( context == null ) ?
assertionFailed( Messages.format( Messages.SOURCE_NULL_CONTEXT ) ) :
context.createMarshaller(),
( contentObject == null ) ?
assertionFailed( Messages.format( Messages.SOURCE_NULL_CONTENT ) ) :
contentObject);
}
/**
* Creates a new {@link javax.xml.transform.Source} for the given content object.
*
* @param marshaller
* A marshaller instance that will be used to marshal
* contentObject into XML. This must be
* created from a JAXBContext that was used to build
* contentObject and must not be null.
* @param contentObject
* An instance of a JAXB-generated class, which will be
* used as a {@link javax.xml.transform.Source} (by marshalling it into XML). It must
* not be null.
* @throws JAXBException if an error is encountered while creating the
* JAXBSource or if either of the parameters are null.
*/
public JAXBSource( Marshaller marshaller, Object contentObject )
throws JAXBException {
if( marshaller == null )
throw new JAXBException(
Messages.format( Messages.SOURCE_NULL_MARSHALLER ) );
if( contentObject == null )
throw new JAXBException(
Messages.format( Messages.SOURCE_NULL_CONTENT ) );
this.marshaller = marshaller;
this.contentObject = contentObject;
super.setXMLReader(pseudoParser);
// pass a dummy InputSource. We don't care
super.setInputSource(new InputSource());
}
private final Marshaller marshaller;
private final Object contentObject;
// this object will pretend as an XMLReader.
// no matter what parameter is specified to the parse method,
// it just parse the contentObject.
private final XMLReader pseudoParser = new XMLReader() {
public boolean getFeature(String name) throws SAXNotRecognizedException {
if(name.equals("http://xml.org/sax/features/namespaces"))
return true;
if(name.equals("http://xml.org/sax/features/namespace-prefixes"))
return false;
throw new SAXNotRecognizedException(name);
}
public void setFeature(String name, boolean value) throws SAXNotRecognizedException {
if(name.equals("http://xml.org/sax/features/namespaces") && value)
return;
if(name.equals("http://xml.org/sax/features/namespace-prefixes") && !value)
return;
throw new SAXNotRecognizedException(name);
}
public Object getProperty(String name) throws SAXNotRecognizedException {
if( "http://xml.org/sax/properties/lexical-handler".equals(name) ) {
return lexicalHandler;
}
throw new SAXNotRecognizedException(name);
}
public void setProperty(String name, Object value) throws SAXNotRecognizedException {
if( "http://xml.org/sax/properties/lexical-handler".equals(name) ) {
this.lexicalHandler = (LexicalHandler)value;
return;
}
throw new SAXNotRecognizedException(name);
}
private LexicalHandler lexicalHandler;
// we will store this value but never use it by ourselves.
private EntityResolver entityResolver;
public void setEntityResolver(EntityResolver resolver) {
this.entityResolver = resolver;
}
public EntityResolver getEntityResolver() {
return entityResolver;
}
private DTDHandler dtdHandler;
public void setDTDHandler(DTDHandler handler) {
this.dtdHandler = handler;
}
public DTDHandler getDTDHandler() {
return dtdHandler;
}
// SAX allows ContentHandler to be changed during the parsing,
// but JAXB doesn't. So this repeater will sit between those
// two components.
private XMLFilterImpl repeater = new XMLFilterImpl();
public void setContentHandler(ContentHandler handler) {
repeater.setContentHandler(handler);
}
public ContentHandler getContentHandler() {
return repeater.getContentHandler();
}
private ErrorHandler errorHandler;
public void setErrorHandler(ErrorHandler handler) {
this.errorHandler = handler;
}
public ErrorHandler getErrorHandler() {
return errorHandler;
}
public void parse(InputSource input) throws SAXException {
parse();
}
public void parse(String systemId) throws SAXException {
parse();
}
public void parse() throws SAXException {
// parses a content object by using the given marshaller
// SAX events will be sent to the repeater, and the repeater
// will further forward it to an appropriate component.
try {
marshaller.marshal( contentObject, repeater );
} catch( JAXBException e ) {
// wrap it to a SAXException
SAXParseException se =
new SAXParseException( e.getMessage(),
null, null, -1, -1, e );
// if the consumer sets an error handler, it is our responsibility
// to notify it.
if(errorHandler!=null)
errorHandler.fatalError(se);
// this is a fatal error. Even if the error handler
// returns, we will abort anyway.
throw se;
}
}
};
/**
* Hook to throw exception from the middle of a contructor chained call
* to this
*/
private static Marshaller assertionFailed( String message )
throws JAXBException {
throw new JAXBException( message );
}
}