Commons JXPath example source code file (KeyManagerUtils.java)

This example Commons JXPath source code file (KeyManagerUtils.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Commons JXPath tags/keywords

basicnodeset, basicnodeset, extendedkeymanager, extendedkeymanager, keymanager, keymanagerutils, nodeset, object, pointer, singlenodeextendedkeymanager, singlenodeextendedkeymanager, string, string

The Commons JXPath KeyManagerUtils.java source code

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.commons.jxpath.util;

import org.apache.commons.jxpath.BasicNodeSet;
import org.apache.commons.jxpath.ExtendedKeyManager;
import org.apache.commons.jxpath.JXPathContext;
import org.apache.commons.jxpath.KeyManager;
import org.apache.commons.jxpath.NodeSet;
import org.apache.commons.jxpath.Pointer;
import org.apache.commons.jxpath.ri.InfoSetUtil;

/**
 * Utility class.
 *
 * @author Matt Benson
 * @since JXPath 1.3
 * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
 */
public class KeyManagerUtils {
    /**
     * Adapt KeyManager to implement ExtendedKeyManager.
     */
    private static class SingleNodeExtendedKeyManager implements
            ExtendedKeyManager {
        private KeyManager delegate;

        /**
         * Create a new SingleNodeExtendedKeyManager.
         * @param delegate KeyManager to wrap
         */
        public SingleNodeExtendedKeyManager(KeyManager delegate) {
            this.delegate = delegate;
        }

        public NodeSet getNodeSetByKey(JXPathContext context, String key,
                Object value) {
            Pointer pointer = delegate.getPointerByKey(context, key, InfoSetUtil.stringValue(value));
            BasicNodeSet result = new BasicNodeSet();
            result.add(pointer);
            return result;
        }

        public Pointer getPointerByKey(JXPathContext context, String keyName,
                String keyValue) {
            return delegate.getPointerByKey(context, keyName, keyValue);
        }
    }

    /**
     * Get an ExtendedKeyManager from the specified KeyManager.
     * @param keyManager to adapt, if necessary
     * @return <code>keyManager if it implements ExtendedKeyManager
     *         or a basic single-result ExtendedKeyManager that delegates to
     *         <code>keyManager.
     */
    public static ExtendedKeyManager getExtendedKeyManager(KeyManager keyManager) {
        return keyManager instanceof ExtendedKeyManager ? (ExtendedKeyManager) keyManager
                : new SingleNodeExtendedKeyManager(keyManager);
    }
}