/*

 * 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

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 */

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

import javax.xml.namespace.NamespaceContext;

import org.xml.sax.Attributes;

import org.xml.sax.SAXException;

/**

 * {@link XmlVisitor} decorator that interns all string tokens.

 *

 * @author Kohsuke Kawaguchi

 */

public final class InterningXmlVisitor implements XmlVisitor {

    private final XmlVisitor next;

    private final AttributesImpl attributes = new AttributesImpl();

    public InterningXmlVisitor(XmlVisitor next) {

        this.next = next;

    }

    public void startDocument(LocatorEx locator, NamespaceContext nsContext) throws SAXException {

        next.startDocument(locator,nsContext);

    }

    public void endDocument() throws SAXException {

        next.endDocument();

    }

    public void startElement(TagName tagName ) throws SAXException {

        attributes.setAttributes(tagName.atts);

        tagName.atts = attributes;

        tagName.uri = intern(tagName.uri);

        tagName.local = intern(tagName.local);

        next.startElement(tagName);

    }

    public void endElement(TagName tagName ) throws SAXException {

        tagName.uri = intern(tagName.uri);

        tagName.local = intern(tagName.local);

        next.endElement(tagName);

    }

    public void startPrefixMapping( String prefix, String nsUri ) throws SAXException {

        next.startPrefixMapping(intern(prefix),intern(nsUri));

    }

    public void endPrefixMapping( String prefix ) throws SAXException {

        next.endPrefixMapping(intern(prefix));

    }

    public void text( CharSequence pcdata ) throws SAXException {

        next.text(pcdata);

    }

    public UnmarshallingContext getContext() {

        return next.getContext();

    }

    public TextPredictor getPredictor() {

        return next.getPredictor();

    }

    private static class AttributesImpl implements Attributes {

        private Attributes core;

        void setAttributes(Attributes att) {

            this.core = att;

        }

        public int getIndex(String qName) {

            return core.getIndex(qName);

        }

        public int getIndex(String uri, String localName) {

            return core.getIndex(uri, localName);

        }

        public int getLength() {

            return core.getLength();

        }

        public String getLocalName(int index) {

            return intern(core.getLocalName(index));

        }

        public String getQName(int index) {

            return intern(core.getQName(index));

        }

        public String getType(int index) {

            return intern(core.getType(index));

        }

        public String getType(String qName) {

            return intern(core.getType(qName));

        }

        public String getType(String uri, String localName) {

            return intern(core.getType(uri, localName));

        }

        public String getURI(int index) {

            return intern(core.getURI(index));

        }

        //

        // since values may vary a lot,

        // we don't (probably shouldn't) intern values.

        //

        public String getValue(int index) {

            return core.getValue(index);

        }

        public String getValue(String qName) {

            return core.getValue(qName);

        }

        public String getValue(String uri, String localName) {

            return core.getValue(uri, localName);

        }

    }

    private static String intern(String s) {

        if(s==null)     return null;

        else            return s.intern();

    }

}