/*

 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Copyright  1999-2004 The Apache Software Foundation.

 *

 *  Licensed under the Apache License, Version 2.0 (the "License");

 *  you may not use this file except in compliance with the License.

 *  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 *  Unless required by applicable law or agreed to in writing, software

 *  distributed under the License is distributed on an "AS IS" BASIS,

 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 *  See the License for the specific language governing permissions and

 *  limitations under the License.

 *

 */

package com.sun.org.apache.xml.internal.security.utils;

import com.sun.org.apache.xpath.internal.CachedXPathAPI;

import org.w3c.dom.Document;

/**

 * @author Raul Benito

 */

public class CachedXPathAPIHolder {

         static java.util.logging.Logger log =

                java.util.logging.Logger.getLogger(CachedXPathAPIHolder.class.getName());

    static ThreadLocal  local=new ThreadLocal();

    static ThreadLocal localDoc=new ThreadLocal();

        /**

         * Sets the doc for the xpath transformation. Resets the cache if needed

         * @param doc

         */

        public static void setDoc(Document doc) {

       if (localDoc.get()!=doc) {

            CachedXPathAPI cx=(CachedXPathAPI)local.get();

            if (cx==null) {

               cx=new CachedXPathAPI();

               local.set(cx);

               localDoc.set(doc);

               return;

            }

            //Different docs reset.

            cx.getXPathContext().reset();

            localDoc.set(doc);

        }

        }

    /**

     * @return the cachexpathapi for this thread

     */

    public static CachedXPathAPI getCachedXPathAPI() {

        CachedXPathAPI cx=(CachedXPathAPI)local.get();

        if (cx==null) {

            cx=new CachedXPathAPI();

            local.set(cx);

            localDoc.set(null);

        }

        return cx;

    }

}