/*
* Copyright 2003 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.xml.bind.util;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.UnmarshallerHandler;
import javax.xml.transform.sax.SAXResult;
/**
* JAXP {@link javax.xml.transform.Result} implementation
* that unmarshals a JAXB object.
*
* <p>
* This utility class is useful to combine JAXB with
* other Java/XML technologies.
*
* <p>
* The following example shows how to use JAXB to unmarshal a document
* resulting from an XSLT transformation.
*
* <blockquote>
* <pre>
* JAXBResult result = new JAXBResult(
* JAXBContext.newInstance("org.acme.foo") );
*
* // set up XSLT transformation
* TransformerFactory tf = TransformerFactory.newInstance();
* Transformer t = tf.newTransformer(new StreamSource("test.xsl"));
*
* // run transformation
* t.transform(new StreamSource("document.xml"),result);
*
* // obtain the unmarshalled content tree
* Object o = result.getResult();
* </pre>
* </blockquote>
*
* <p>
* The fact that JAXBResult derives from SAXResult is an implementation
* detail. Thus in general applications are strongly discouraged from
* accessing methods defined on SAXResult.
*
* <p>
* In particular it shall never attempt to call the setHandler,
* setLexicalHandler, and setSystemId methods.
*
* @author
* Kohsuke Kawaguchi ([email protected])
*/
public class JAXBResult extends SAXResult {
/**
* Creates a new instance that uses the specified
* JAXBContext to unmarshal.
*
* @param context The JAXBContext that will be used to create the
* necessary Unmarshaller. This parameter must not be null.
* @exception JAXBException if an error is encountered while creating the
* JAXBResult or if the context parameter is null.
*/
public JAXBResult( JAXBContext context ) throws JAXBException {
this( ( context == null ) ? assertionFailed() : context.createUnmarshaller() );
}
/**
* Creates a new instance that uses the specified
* Unmarshaller to unmarshal an object.
*
* <p>
* This JAXBResult object will use the specified Unmarshaller
* instance. It is the caller's responsibility not to use the
* same Unmarshaller for other purposes while it is being
* used by this object.
*
* <p>
* The primary purpose of this method is to allow the client
* to configure Unmarshaller. Unless you know what you are doing,
* it's easier and safer to pass a JAXBContext.
*
* @param _unmarshaller the unmarshaller. This parameter must not be null.
* @throws JAXBException if an error is encountered while creating the
* JAXBResult or the Unmarshaller parameter is null.
*/
public JAXBResult( Unmarshaller _unmarshaller ) throws JAXBException {
if( _unmarshaller == null )
throw new JAXBException(
Messages.format( Messages.RESULT_NULL_UNMARSHALLER ) );
this.unmarshallerHandler = _unmarshaller.getUnmarshallerHandler();
super.setHandler(unmarshallerHandler);
}
/**
* Unmarshaller that will be used to unmarshal
* the input documents.
*/
private final UnmarshallerHandler unmarshallerHandler;
/**
* Gets the unmarshalled object created by the transformation.
*
* @return
* Always return a non-null object.
*
* @exception IllegalStateException
* if this method is called before an object is unmarshalled.
*
* @exception JAXBException
* if there is any unmarshalling error.
* Note that the implementation is allowed to throw SAXException
* during the parsing when it finds an error.
*/
public Object getResult() throws JAXBException {
return unmarshallerHandler.getResult();
}
/**
* Hook to throw exception from the middle of a contructor chained call
* to this
*/
private static Unmarshaller assertionFailed() throws JAXBException {
throw new JAXBException( Messages.format( Messages.RESULT_NULL_CONTEXT ) );
}
}
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