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 * Copyright (c) 1997, 2014, 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

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package com.sun.xml.internal.bind.v2.runtime.unmarshaller;

import java.lang.reflect.Constructor;

import javax.xml.stream.Location;

import javax.xml.stream.XMLStreamConstants;

import javax.xml.stream.XMLStreamException;

import javax.xml.stream.XMLStreamReader;

import com.sun.xml.internal.bind.WhiteSpaceProcessor;

import org.xml.sax.Attributes;

import org.xml.sax.SAXException;

/**

 * Reads XML from StAX {@link XMLStreamReader} and

 * feeds events to {@link XmlVisitor}.

 * <p>

 * TODO:

 * Finding the optimized FI implementations is a bit hacky and not very

 * extensible. Can we use the service provider mechanism in general for

 * concrete implementations of StAXConnector.

 *

 * @author Ryan.Shoemaker@Sun.COM

 * @author Kohsuke Kawaguchi

 * @version JAXB 2.0

 */

class StAXStreamConnector extends StAXConnector {

    /**

     * Creates a {@link StAXConnector} from {@link XMLStreamReader}.

     *

     * This method checks if the parser is FI parser and acts accordingly.

     */

    public static StAXConnector create(XMLStreamReader reader, XmlVisitor visitor) {

        // try optimized codepath

        final Class readerClass = reader.getClass();

        if (FI_STAX_READER_CLASS != null && FI_STAX_READER_CLASS.isAssignableFrom(readerClass) && FI_CONNECTOR_CTOR!=null) {

            try {

                return FI_CONNECTOR_CTOR.newInstance(reader,visitor);

            } catch (Exception t) {

            }

        }

        // Quick hack until SJSXP fixes 6270116

        boolean isZephyr = readerClass.getName().equals("com.sun.xml.internal.stream.XMLReaderImpl");

        if (getBoolProp(reader,"org.codehaus.stax2.internNames") &&

            ; // no need for interning

        else

        if (isZephyr)

            ; // no need for interning

        else

        if (checkImplementaionNameOfSjsxp(reader))

            ; // no need for interning.

        else

            visitor = new InterningXmlVisitor(visitor);

        if (STAX_EX_READER_CLASS!=null && STAX_EX_READER_CLASS.isAssignableFrom(readerClass)) {

            try {

                return STAX_EX_CONNECTOR_CTOR.newInstance(reader,visitor);

            } catch (Exception t) {

            }

        }

        return new StAXStreamConnector(reader,visitor);

    }

    private static boolean checkImplementaionNameOfSjsxp(XMLStreamReader reader) {

        try {

            Object name = reader.getProperty("http://java.sun.com/xml/stream/properties/implementation-name");

            return name!=null && name.equals("sjsxp");

        } catch (Exception e) {

            // be defensive against broken StAX parsers since javadoc is not clear

            // about when an error happens

            return false;

        }

    }

    private static boolean getBoolProp(XMLStreamReader r, String n) {

        try {

            Object o = r.getProperty(n);

            if(o instanceof Boolean)    return (Boolean)o;

            return false;

        } catch (Exception e) {

            // be defensive against broken StAX parsers since javadoc is not clear

            // about when an error happens

            return false;

        }

    }

    // StAX event source

    private final XMLStreamReader staxStreamReader;

    /**

     * SAX may fire consecutive characters event, but we don't allow it.

     * so use this buffer to perform buffering.

     */

    protected final StringBuilder buffer = new StringBuilder();

    /**

     * Set to true if the text() event is reported, and therefore

     * the following text() event should be suppressed.

     */

    protected boolean textReported = false;

    protected StAXStreamConnector(XMLStreamReader staxStreamReader, XmlVisitor visitor) {

        super(visitor);

        this.staxStreamReader = staxStreamReader;

    }

    public void bridge() throws XMLStreamException {

        try {

            // remembers the nest level of elements to know when we are done.

            int depth=0;

            // if the parser is at the start tag, proceed to the first element

            int event = staxStreamReader.getEventType();

            if(event == XMLStreamConstants.START_DOCUMENT) {

                // nextTag doesn't correctly handle DTDs

                while( !staxStreamReader.isStartElement() )

                    event = staxStreamReader.next();

            }

            if( event!=XMLStreamConstants.START_ELEMENT)

                throw new IllegalStateException("The current event is not START_ELEMENT\n but " + event);

            handleStartDocument(staxStreamReader.getNamespaceContext());

            OUTER:

            while(true) {

                // These are all of the events listed in the javadoc for

                // XMLEvent.

                // The spec only really describes 11 of them.

                switch (event) {

                    case XMLStreamConstants.START_ELEMENT :

                        handleStartElement();

                        depth++;

                        break;

                    case XMLStreamConstants.END_ELEMENT :

                        depth--;

                        handleEndElement();

                        if(depth==0)    break OUTER;

                        break;

                    case XMLStreamConstants.CHARACTERS :

                    case XMLStreamConstants.CDATA :

                    case XMLStreamConstants.SPACE :

                        handleCharacters();

                        break;

                    // otherwise simply ignore

                }

                event=staxStreamReader.next();

            }

            staxStreamReader.next();    // move beyond the end tag.

            handleEndDocument();

        } catch (SAXException e) {

            throw new XMLStreamException(e);

        }

    }

    protected Location getCurrentLocation() {

        return staxStreamReader.getLocation();

    }

    protected String getCurrentQName() {

        return getQName(staxStreamReader.getPrefix(),staxStreamReader.getLocalName());

    }

    private void handleEndElement() throws SAXException {

        processText(false);

        // fire endElement

        tagName.uri = fixNull(staxStreamReader.getNamespaceURI());

        tagName.local = staxStreamReader.getLocalName();

        visitor.endElement(tagName);

        // end namespace bindings

        int nsCount = staxStreamReader.getNamespaceCount();

        for (int i = nsCount - 1; i >= 0; i--) {

            visitor.endPrefixMapping(fixNull(staxStreamReader.getNamespacePrefix(i)));

        }

    }

    private void handleStartElement() throws SAXException {

        processText(true);

        // start namespace bindings

        int nsCount = staxStreamReader.getNamespaceCount();

        for (int i = 0; i < nsCount; i++) {

            visitor.startPrefixMapping(

        }

        // fire startElement

        tagName.uri = fixNull(staxStreamReader.getNamespaceURI());

        tagName.local = staxStreamReader.getLocalName();

        tagName.atts = attributes;

        visitor.startElement(tagName);

    }

    /**

     * Proxy of {@link Attributes} that read from {@link XMLStreamReader}.

     */

    private final Attributes attributes = new Attributes() {

        public int getLength() {

            return staxStreamReader.getAttributeCount();

        }

        public String getURI(int index) {

            String uri = staxStreamReader.getAttributeNamespace(index);

            if(uri==null)   return "";

            return uri;

        }

        public String getLocalName(int index) {

            return staxStreamReader.getAttributeLocalName(index);

        }

        public String getQName(int index) {

            String prefix = staxStreamReader.getAttributePrefix(index);

            if(prefix==null || prefix.length()==0)

                return getLocalName(index);

            else

                return prefix + ':' + getLocalName(index);

        }

        public String getType(int index) {

            return staxStreamReader.getAttributeType(index);

        }

        public String getValue(int index) {

            return staxStreamReader.getAttributeValue(index);

        }

        public int getIndex(String uri, String localName) {

            for( int i=getLength()-1; i>=0; i-- )

                if( localName.equals(getLocalName(i)) && uri.equals(getURI(i)))

                    return i;

            return -1;

        }

        // this method sholdn't be used that often (if at all)

        // so it's OK to be slow.

        public int getIndex(String qName) {

            for( int i=getLength()-1; i>=0; i-- ) {

                if(qName.equals(getQName(i)))

                    return i;

            }

            return -1;

        }

        public String getType(String uri, String localName) {

            int index = getIndex(uri,localName);

            if(index<0)     return null;

            return getType(index);

        }

        public String getType(String qName) {

            int index = getIndex(qName);

            if(index<0)     return null;

            return getType(index);

        }

        public String getValue(String uri, String localName) {

            int index = getIndex(uri,localName);

            if(index<0)     return null;

            return getValue(index);

        }

        public String getValue(String qName) {

            int index = getIndex(qName);

            if(index<0)     return null;

            return getValue(index);

        }

    };

    protected void handleCharacters() throws XMLStreamException, SAXException {

        if( predictor.expectText() )

            buffer.append(

    }

    private void processText( boolean ignorable ) throws SAXException {

        if( predictor.expectText() && (!ignorable || !WhiteSpaceProcessor.isWhiteSpace(buffer) || context.getCurrentState().isMixed())) {

            if(textReported) {

                textReported = false;

            } else {

                visitor.text(buffer);

            }

        }

        buffer.setLength(0);

    }

    /**

     * Reference to FI's StAXReader class, if FI can be loaded.

     */

    private static final Class FI_STAX_READER_CLASS = initFIStAXReaderClass();

    private static final Constructor<? extends StAXConnector> FI_CONNECTOR_CTOR = initFastInfosetConnectorClass();

    private static Class initFIStAXReaderClass() {

        try {

            Class<?> fisr = Class.forName("com.sun.xml.internal.org.jvnet.fastinfoset.stax.FastInfosetStreamReader");

            Class<?> sdp = Class.forName("com.sun.xml.internal.fastinfoset.stax.StAXDocumentParser");

            // Check if StAXDocumentParser implements FastInfosetStreamReader

            if (fisr.isAssignableFrom(sdp))

                return sdp;

            else

                return null;

        } catch (Throwable e) {

            return null;

        }

    }

    private static Constructor<? extends StAXConnector> initFastInfosetConnectorClass() {

        try {

            if (FI_STAX_READER_CLASS == null)

                return null;

            Class c = Class.forName(

                    "com.sun.xml.internal.bind.v2.runtime.unmarshaller.FastInfosetConnector");

            return c.getConstructor(FI_STAX_READER_CLASS,XmlVisitor.class);

        } catch (Throwable e) {

            return null;

        }

    }

    //

    // reference to StAXEx classes

    //

    private static final Class STAX_EX_READER_CLASS = initStAXExReader();

    private static final Constructor<? extends StAXConnector> STAX_EX_CONNECTOR_CTOR = initStAXExConnector();

    private static Class initStAXExReader() {

        try {

            return Class.forName("com.sun.xml.internal.org.jvnet.staxex.XMLStreamReaderEx");

        } catch (Throwable e) {

            return null;

        }

    }

    private static Constructor<? extends StAXConnector> initStAXExConnector() {

        try {

            Class c = Class.forName("com.sun.xml.internal.bind.v2.runtime.unmarshaller.StAXExConnector");

            return c.getConstructor(STAX_EX_READER_CLASS,XmlVisitor.class);

        } catch (Throwable e) {

            return null;

        }

    }

}