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 * 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.

 *

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package com.sun.tools.internal.xjc.reader.internalizer;

import java.util.Set;

import java.util.HashSet;

import java.util.Arrays;

import com.sun.tools.internal.xjc.reader.Const;

import org.xml.sax.Attributes;

import org.xml.sax.ContentHandler;

import org.xml.sax.EntityResolver;

import org.xml.sax.ErrorHandler;

import org.xml.sax.Locator;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

import org.xml.sax.XMLReader;

import org.xml.sax.helpers.LocatorImpl;

import org.xml.sax.helpers.XMLFilterImpl;

/**

 * Checks the jaxb:version attribute on a XML Schema document.

 *

 * jaxb:version is optional if no binding customization is used,

 * but if present, its value must be "1.0".

 *

 * @author

 *     Kohsuke Kawaguchi (kohsuke.kawaguchi@sun.com)

 */

public class VersionChecker extends XMLFilterImpl {

    /**

     * We store the value of the version attribute in this variable

     * when we hit the root element.

     */

    private String version = null ;

    /** Will be set to true once we hit the root element. */

    private boolean seenRoot = false;

    /** Will be set to true once we hit a binding declaration. */

    private boolean seenBindings = false;

    private Locator locator;

    /**

     * Stores the location of the start tag of the root tag.

     */

    private Locator rootTagStart;

    public VersionChecker( XMLReader parent ) {

        setParent(parent);

    }

    public VersionChecker( ContentHandler handler,ErrorHandler eh,EntityResolver er ) {

        setContentHandler(handler);

        if(eh!=null)    setErrorHandler(eh);

        if(er!=null)    setEntityResolver(er);

    }

    public void startElement(String namespaceURI, String localName, String qName, Attributes atts)

        throws SAXException {

        super.startElement(namespaceURI, localName, qName, atts);

        if(!seenRoot) {

            // if this is the root element

            seenRoot = true;

            rootTagStart = new LocatorImpl(locator);

            version = atts.getValue(Const.JAXB_NSURI,"version");

            if( namespaceURI.equals(Const.JAXB_NSURI) ) {

                String version2 = atts.getValue("","version");

                if( version!=null && version2!=null ) {

                    // we have both @version and @jaxb:version. error.

                    SAXParseException e = new SAXParseException(

                        Messages.format( Messages.TWO_VERSION_ATTRIBUTES ), locator );

                    getErrorHandler().error(e);

                }

                if( version==null )

                    version = version2;

            }

        }

        if( Const.JAXB_NSURI.equals(namespaceURI) )

            seenBindings = true;

    }

    public void endDocument() throws SAXException {

        super.endDocument();

        if( seenBindings && version==null ) {

            // if we see a binding declaration but not version attribute

            SAXParseException e = new SAXParseException(

                Messages.format(Messages.ERR_VERSION_NOT_FOUND),rootTagStart);

            getErrorHandler().error(e);

        }

        // if present, the value must be either 1.0 or 2.0

        if( version!=null && !VERSIONS.contains(version) ) {

            SAXParseException e = new SAXParseException(

                Messages.format(Messages.ERR_INCORRECT_VERSION),rootTagStart);

            getErrorHandler().error(e);

        }

    }

    public void setDocumentLocator(Locator locator) {

        super.setDocumentLocator(locator);

        this.locator = locator;

    }

    private static final Set<String> VERSIONS = new HashSet<String>(Arrays.asList("1.0","2.0","2.1"));

}