/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */
package javax.xml.bind;

import org.xml.sax.ContentHandler;

/**
 * Unmarshaller implemented as SAX ContentHandler.
 * 
 * <p>
 * Applications can use this interface to use their JAXB provider as a component 
 * in an XML pipeline.  For example:
 * 
 * <pre>
 *       JAXBContext context = JAXBContext.newInstance( "org.acme.foo" );
 *
 *       Unmarshaller unmarshaller = context.createUnmarshaller();
 * 
 *       UnmarshallerHandler unmarshallerHandler = unmarshaller.getUnmarshallerHandler();
 *
 *       SAXParserFactory spf = SAXParserFactory.newInstance();
 *       spf.setNamespaceAware( true );
 * 
 *       XMLReader xmlReader = spf.newSAXParser().getXMLReader();
 *       xmlReader.setContentHandler( unmarshallerHandler );
 *       xmlReader.parse(new InputSource( new FileInputStream( XML_FILE ) ) );
 *
 *       MyObject myObject= (MyObject)unmarshallerHandler.getResult();                          
 * </pre>
 * 
 * <p>
 * This interface is reusable: even if the user fails to unmarshal
 * an object, s/he can still start a new round of unmarshalling.
 * 
 * @author <ul><li>Kohsuke KAWAGUCHI, Sun Microsystems, Inc.</li></ul>
 * @see Unmarshaller#getUnmarshallerHandler()
 * @since JAXB1.0
 */
public interface UnmarshallerHandler extends ContentHandler
{
    /**
     * Obtains the unmarshalled result.
     * 
     * This method can be called only after this handler
     * receives the endDocument SAX event.
     * 
     * @exception IllegalStateException
     *      if this method is called before this handler
     *      receives the endDocument event.
     * 
     * @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.
     * 
     * @return
     *      always return a non-null valid object which was unmarshalled.
     */
    Object getResult() throws JAXBException, IllegalStateException;
}
