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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 com.sun.istack.internal.SAXParseException2;

import org.xml.sax.Attributes;

import org.xml.sax.Locator;

import org.xml.sax.SAXException;

import org.xml.sax.SAXParseException;

import org.xml.sax.helpers.XMLFilterImpl;

import java.io.File;

import java.io.IOException;

import java.net.URI;

import java.net.URISyntaxException;

/**

 * XMLFilter that finds references to other schema files from

 * SAX events.

 * This implementation is a base implementation for typical case

 * where we just need to look for a particular attribute which

 * contains an URL to another schema file.

 *

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

 */

public abstract class AbstractReferenceFinderImpl extends XMLFilterImpl {

    protected final DOMForest parent;

    protected AbstractReferenceFinderImpl(DOMForest _parent) {

        this.parent = _parent;

    }

    /**

     * IF the given element contains a reference to an external resource,

     * return its URL.

     *

     * @param nsURI     Namespace URI of the current element

     * @param localName Local name of the current element

     * @return It's OK to return a relative URL.

     */

    protected abstract String findExternalResource(String nsURI, String localName, Attributes atts);

    @Override

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

            throws SAXException {

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

        String relativeRef = findExternalResource(namespaceURI, localName, atts);

        if (relativeRef == null) {

            return; // not found

        }

        try {

            // absolutize URL.

            String lsi = locator.getSystemId();

            String ref;

            URI relRefURI = new URI(relativeRef);

            if (relRefURI.isAbsolute())

                ref = relativeRef;

            else {

                if (lsi.startsWith("jar:")) {

                    int bangIdx = lsi.indexOf('!');

                    if (bangIdx > 0) {

                        ref = lsi.substring(0, bangIdx + 1)

                                + new URI(lsi.substring(bangIdx + 1)).resolve(new URI(relativeRef)).toString();

                    } else {

                        ref = relativeRef;

                    }

                } else {

                    ref = new URI(lsi).resolve(new URI(relativeRef)).toString();

                }

            }

            // then parse this schema as well,

            // but don't mark this document as a root.

            if (parent != null) { // this is there to allow easier testing

                parent.parse(ref, false);

            }

        } catch (URISyntaxException e) {

            String msg = e.getMessage();

            if (new File(relativeRef).exists()) {

                msg = Messages.format(Messages.ERR_FILENAME_IS_NOT_URI) + ' ' + msg;

            }

            SAXParseException spe = new SAXParseException2(

                    Messages.format(Messages.ERR_UNABLE_TO_PARSE, relativeRef, msg),

                    locator, e);

            fatalError(spe);

            throw spe;

        } catch (IOException e) {

            SAXParseException spe = new SAXParseException2(

                    Messages.format(Messages.ERR_UNABLE_TO_PARSE, relativeRef, e.getMessage()),

                    locator, e);

            fatalError(spe);

            throw spe;

        }

    }

    private Locator locator;

    @Override

    public void setDocumentLocator(Locator locator) {

        super.setDocumentLocator(locator);

        this.locator = locator;

    }

}