aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: package com.sun.xml.internal.bind.v2.runtime.unmarshaller;
aoqi@0: 
aoqi@0: import java.util.Iterator;
aoqi@0: 
aoqi@0: import javax.xml.namespace.QName;
aoqi@0: import javax.xml.stream.Location;
aoqi@0: import javax.xml.stream.XMLEventReader;
aoqi@0: import javax.xml.stream.XMLStreamConstants;
aoqi@0: import javax.xml.stream.XMLStreamException;
aoqi@0: import javax.xml.stream.events.Attribute;
aoqi@0: import javax.xml.stream.events.Characters;
aoqi@0: import javax.xml.stream.events.EndElement;
aoqi@0: import javax.xml.stream.events.Namespace;
aoqi@0: import javax.xml.stream.events.StartElement;
aoqi@0: import javax.xml.stream.events.XMLEvent;
aoqi@0: 
aoqi@0: import org.xml.sax.Attributes;
aoqi@0: import org.xml.sax.SAXException;
aoqi@0: import org.xml.sax.helpers.AttributesImpl;
aoqi@0: 
aoqi@0: /**
aoqi@0:  * This is a simple utility class that adapts StAX events from an
aoqi@0:  * {@link XMLEventReader} to unmarshaller events on a
aoqi@0:  * {@link XmlVisitor}, bridging between the two
aoqi@0:  * parser technologies.
aoqi@0:  *
aoqi@0:  * @author Ryan.Shoemaker@Sun.COM
aoqi@0:  * @version 1.0
aoqi@0:  */
aoqi@0: final class StAXEventConnector extends StAXConnector {
aoqi@0: 
aoqi@0:     // StAX event source
aoqi@0:     private final XMLEventReader staxEventReader;
aoqi@0: 
aoqi@0:     /** Current event. */
aoqi@0:     private XMLEvent event;
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Shared and reused {@link Attributes}.
aoqi@0:      */
aoqi@0:     private final AttributesImpl attrs = new AttributesImpl();
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * SAX may fire consective characters event, but we don't allow it.
aoqi@0:      * so use this buffer to perform buffering.
aoqi@0:      */
aoqi@0:     private final StringBuilder buffer = new StringBuilder();
aoqi@0: 
aoqi@0:     private boolean seenText;
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Construct a new StAX to SAX adapter that will convert a StAX event
aoqi@0:      * stream into a SAX event stream.
aoqi@0:      *
aoqi@0:      * @param staxCore
aoqi@0:      *                StAX event source
aoqi@0:      * @param visitor
aoqi@0:      *                sink
aoqi@0:      */
aoqi@0:     public StAXEventConnector(XMLEventReader staxCore, XmlVisitor visitor) {
aoqi@0:         super(visitor);
aoqi@0:         staxEventReader = staxCore;
aoqi@0:     }
aoqi@0: 
aoqi@0:     public void bridge() throws XMLStreamException {
aoqi@0: 
aoqi@0:         try {
aoqi@0:             // remembers the nest level of elements to know when we are done.
aoqi@0:             int depth=0;
aoqi@0: 
aoqi@0:             event = staxEventReader.peek();
aoqi@0: 
aoqi@0:             if( !event.isStartDocument() && !event.isStartElement() )
aoqi@0:                 throw new IllegalStateException();
aoqi@0: 
aoqi@0:             // if the parser is on START_DOCUMENT, skip ahead to the first element
aoqi@0:             do {
aoqi@0:                 event = staxEventReader.nextEvent();
aoqi@0:             } while( !event.isStartElement() );
aoqi@0: 
aoqi@0:             handleStartDocument(event.asStartElement().getNamespaceContext());
aoqi@0: 
aoqi@0:             OUTER:
aoqi@0:             while(true) {
aoqi@0:                 // These are all of the events listed in the javadoc for
aoqi@0:                 // XMLEvent.
aoqi@0:                 // The spec only really describes 11 of them.
aoqi@0:                 switch (event.getEventType()) {
aoqi@0:                     case XMLStreamConstants.START_ELEMENT :
aoqi@0:                         handleStartElement(event.asStartElement());
aoqi@0:                         depth++;
aoqi@0:                         break;
aoqi@0:                     case XMLStreamConstants.END_ELEMENT :
aoqi@0:                         depth--;
aoqi@0:                         handleEndElement(event.asEndElement());
aoqi@0:                         if(depth==0)    break OUTER;
aoqi@0:                         break;
aoqi@0:                     case XMLStreamConstants.CHARACTERS :
aoqi@0:                     case XMLStreamConstants.CDATA :
aoqi@0:                     case XMLStreamConstants.SPACE :
aoqi@0:                         handleCharacters(event.asCharacters());
aoqi@0:                         break;
aoqi@0:                 }
aoqi@0: 
aoqi@0: 
aoqi@0:                 event=staxEventReader.nextEvent();
aoqi@0:             }
aoqi@0: 
aoqi@0:             handleEndDocument();
aoqi@0:             event = null; // avoid keeping a stale reference
aoqi@0:         } catch (SAXException e) {
aoqi@0:             throw new XMLStreamException(e);
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     protected Location getCurrentLocation() {
aoqi@0:         return event.getLocation();
aoqi@0:     }
aoqi@0: 
aoqi@0:     protected String getCurrentQName() {
aoqi@0:         QName qName;
aoqi@0:         if(event.isEndElement())
aoqi@0:             qName = event.asEndElement().getName();
aoqi@0:         else
aoqi@0:             qName = event.asStartElement().getName();
aoqi@0:         return getQName(qName.getPrefix(), qName.getLocalPart());
aoqi@0:     }
aoqi@0: 
aoqi@0: 
aoqi@0:     private void handleCharacters(Characters event) throws SAXException, XMLStreamException {
aoqi@0:         if(!predictor.expectText())
aoqi@0:             return;     // text isn't expected. simply skip
aoqi@0: 
aoqi@0:         seenText = true;
aoqi@0: 
aoqi@0:         // check the next event
aoqi@0:         XMLEvent next;
aoqi@0:         while(true) {
aoqi@0:             next = staxEventReader.peek();
aoqi@0:             if(!isIgnorable(next))
aoqi@0:                 break;
aoqi@0:             staxEventReader.nextEvent();
aoqi@0:         }
aoqi@0: 
aoqi@0:         if(isTag(next)) {
aoqi@0:             // this is by far the common case --- you have <foo>abc</foo> or <foo>abc<bar/>...</foo>
aoqi@0:             visitor.text(event.getData());
aoqi@0:             return;
aoqi@0:         }
aoqi@0: 
aoqi@0:         // otherwise we have things like "abc<!-- test -->def".
aoqi@0:         // concatenate all text
aoqi@0:         buffer.append(event.getData());
aoqi@0: 
aoqi@0:         while(true) {
aoqi@0:             while(true) {
aoqi@0:                 next = staxEventReader.peek();
aoqi@0:                 if(!isIgnorable(next))
aoqi@0:                     break;
aoqi@0:                 staxEventReader.nextEvent();
aoqi@0:             }
aoqi@0: 
aoqi@0:             if(isTag(next)) {
aoqi@0:                 // found all adjacent text
aoqi@0:                 visitor.text(buffer);
aoqi@0:                 buffer.setLength(0);
aoqi@0:                 return;
aoqi@0:             }
aoqi@0: 
aoqi@0:             buffer.append(next.asCharacters().getData());
aoqi@0:             staxEventReader.nextEvent();    // consume
aoqi@0:         }
aoqi@0:     }
aoqi@0: 
aoqi@0:     private boolean isTag(XMLEvent event) {
aoqi@0:         int eventType = event.getEventType();
aoqi@0:         return eventType==XMLEvent.START_ELEMENT || eventType==XMLEvent.END_ELEMENT;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private boolean isIgnorable(XMLEvent event) {
aoqi@0:         int eventType = event.getEventType();
aoqi@0:         return eventType==XMLEvent.COMMENT || eventType==XMLEvent.PROCESSING_INSTRUCTION;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private void handleEndElement(EndElement event) throws SAXException {
aoqi@0:         if(!seenText && predictor.expectText()) {
aoqi@0:             visitor.text("");
aoqi@0:         }
aoqi@0: 
aoqi@0:         // fire endElement
aoqi@0:         QName qName = event.getName();
aoqi@0:         tagName.uri = fixNull(qName.getNamespaceURI());
aoqi@0:         tagName.local = qName.getLocalPart();
aoqi@0:         visitor.endElement(tagName);
aoqi@0: 
aoqi@0:         // end namespace bindings
aoqi@0:         for( Iterator<Namespace> i = event.getNamespaces(); i.hasNext();) {
aoqi@0:             String prefix = fixNull(i.next().getPrefix());  // be defensive
aoqi@0:             visitor.endPrefixMapping(prefix);
aoqi@0:         }
aoqi@0: 
aoqi@0:         seenText = false;
aoqi@0:     }
aoqi@0: 
aoqi@0:     private void handleStartElement(StartElement event) throws SAXException {
aoqi@0:         // start namespace bindings
aoqi@0:         for (Iterator i = event.getNamespaces(); i.hasNext();) {
aoqi@0:             Namespace ns = (Namespace)i.next();
aoqi@0:             visitor.startPrefixMapping(
aoqi@0:                 fixNull(ns.getPrefix()),
aoqi@0:                 fixNull(ns.getNamespaceURI()));
aoqi@0:         }
aoqi@0: 
aoqi@0:         // fire startElement
aoqi@0:         QName qName = event.getName();
aoqi@0:         tagName.uri = fixNull(qName.getNamespaceURI());
aoqi@0:         String localName = qName.getLocalPart();
aoqi@0:         tagName.uri = fixNull(qName.getNamespaceURI());
aoqi@0:         tagName.local = localName;
aoqi@0:         tagName.atts = getAttributes(event);
aoqi@0:         visitor.startElement(tagName);
aoqi@0: 
aoqi@0:         seenText = false;
aoqi@0:     }
aoqi@0: 
aoqi@0: 
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Get the attributes associated with the given START_ELEMENT StAXevent.
aoqi@0:      *
aoqi@0:      * @return the StAX attributes converted to an org.xml.sax.Attributes
aoqi@0:      */
aoqi@0:     private Attributes getAttributes(StartElement event) {
aoqi@0:         attrs.clear();
aoqi@0: 
aoqi@0:         // in SAX, namespace declarations are not part of attributes by default.
aoqi@0:         // (there's a property to control that, but as far as we are concerned
aoqi@0:         // we don't use it.) So don't add xmlns:* to attributes.
aoqi@0: 
aoqi@0:         // gather non-namespace attrs
aoqi@0:         for (Iterator i = event.getAttributes(); i.hasNext();) {
aoqi@0:             Attribute staxAttr = (Attribute)i.next();
aoqi@0: 
aoqi@0:             QName name = staxAttr.getName();
aoqi@0:             String uri = fixNull(name.getNamespaceURI());
aoqi@0:             String localName = name.getLocalPart();
aoqi@0:             String prefix = name.getPrefix();
aoqi@0:             String qName;
aoqi@0:             if (prefix == null || prefix.length() == 0)
aoqi@0:                 qName = localName;
aoqi@0:             else
aoqi@0:                 qName = prefix + ':' + localName;
aoqi@0:             String type = staxAttr.getDTDType();
aoqi@0:             String value = staxAttr.getValue();
aoqi@0: 
aoqi@0:             attrs.addAttribute(uri, localName, qName, type, value);
aoqi@0:         }
aoqi@0: 
aoqi@0:         return attrs;
aoqi@0:     }
aoqi@0: }