src/org/apache/xerces/util/AugmentationsImpl.java

/*
 * The Apache Software License, Version 1.1
 *
 *
 * Copyright (c) 2000,2001 The Apache Software Foundation.  All rights 
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:  
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Xerces" and "Apache Software Foundation" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written 
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    nor may "Apache" appear in their name, without prior written
 *    permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation and was
 * originally based on software copyright (c) 1999, International
 * Business Machines, Inc., http://www.apache.org.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.xerces.util;

import java.util.Hashtable;

import org.apache.xerces.xni.Augmentations;

/**
 * This class provides an implementation for Augmentations interface. 
 * Augmentations interface defines a hashtable of additional data that could
 * be passed along the document pipeline. The information can contain extra
 * arguments or infoset augmentations, for example PSVI. This additional
 * information is identified by a String key.
 * <p>
 * 
 * @author Elena Litani, IBM
 */
public class AugmentationsImpl implements Augmentations{
    
    private final Hashtable fAugmentations = new Hashtable();
    
    /**
     * Add additional information identified by a key to the Augmentations structure.
     * 
     * @param key    Identifier, can't be <code>null</code>
     * @param item   Additional information
     *
     * @return the previous value of the specified key in the Augmentations strucutre,
     *         or <code>null</code> if it did not have one.
     */
    public Object putItem (String key, Object item){
        return fAugmentations.put(key, item);

    }


    /**
     * Get information identified by a key from the Augmentations structure
     * 
     * @param key    Identifier, can't be <code>null</code>
     *
     * @return the value to which the key is mapped in the Augmentations structure;
     *         <code>null</code> if the key is not mapped to any value.
     */
    public Object getItem(String key){
        return fAugmentations.get(key);
    }
    
    
    /**
     * Remove additional info from the Augmentations structure
     * 
     * @param key    Identifier, can't be <code>null</code>
     */
    public Object removeItem (String key){
        return fAugmentations.remove(key);
    }

    /**
     * Remove all objects from the Augmentations structure.
     */
    public void clear (){
        fAugmentations.clear();
    }
}