001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.configuration.web;
019    
020    import java.util.ArrayList;
021    import java.util.Collection;
022    import java.util.Iterator;
023    import java.util.List;
024    
025    import javax.servlet.ServletRequest;
026    
027    import org.apache.commons.collections.iterators.EnumerationIterator;
028    
029    /**
030     * A configuration wrapper to read the parameters of a servlet request. This
031     * configuration is read only, adding or removing a property will throw an
032     * UnsupportedOperationException.
033     *
034     * @author <a href="mailto:ebourg@apache.org">Emmanuel Bourg</a>
035     * @version $Revision: 515306 $, $Date: 2007-03-06 22:15:00 +0100 (Di, 06. Mrz 2007) $
036     * @since 1.1
037     */
038    public class ServletRequestConfiguration extends BaseWebConfiguration
039    {
040        /** Stores the wrapped request.*/
041        protected ServletRequest request;
042    
043        /**
044         * Create a ServletRequestConfiguration using the request parameters.
045         *
046         * @param request the servlet request
047         */
048        public ServletRequestConfiguration(ServletRequest request)
049        {
050            this.request = request;
051        }
052    
053        public Object getProperty(String key)
054        {
055            String[] values = request.getParameterValues(key);
056    
057            if (values == null || values.length == 0)
058            {
059                return null;
060            }
061            else if (values.length == 1)
062            {
063                return handleDelimiters(values[0]);
064            }
065            else
066            {
067                // ensure that escape characters in all list elements are removed
068                List result = new ArrayList(values.length);
069                for (int i = 0; i < values.length; i++)
070                {
071                    Object val = handleDelimiters(values[i]);
072                    if (val instanceof Collection)
073                    {
074                        result.addAll((Collection) val);
075                    }
076                    else
077                    {
078                        result.add(val);
079                    }
080                }
081                return result;
082            }
083        }
084    
085        public Iterator getKeys()
086        {
087            return new EnumerationIterator(request.getParameterNames());
088        }
089    }