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    import java.util.Map;
025    
026    import javax.servlet.ServletRequest;
027    
028    /**
029     * A configuration wrapper to read the parameters of a servlet request. This
030     * configuration is read only, adding or removing a property will throw an
031     * UnsupportedOperationException.
032     *
033     * @author <a href="mailto:ebourg@apache.org">Emmanuel Bourg</a>
034     * @version $Id: ServletRequestConfiguration.java 1211131 2011-12-06 20:57:37Z oheger $
035     * @since 1.1
036     */
037    public class ServletRequestConfiguration extends BaseWebConfiguration
038    {
039        /** Stores the wrapped request.*/
040        protected ServletRequest request;
041    
042        /**
043         * Create a ServletRequestConfiguration using the request parameters.
044         *
045         * @param request the servlet request
046         */
047        public ServletRequestConfiguration(ServletRequest request)
048        {
049            this.request = request;
050        }
051    
052        public Object getProperty(String key)
053        {
054            String[] values = request.getParameterValues(key);
055    
056            if (values == null || values.length == 0)
057            {
058                return null;
059            }
060            else if (values.length == 1)
061            {
062                return handleDelimiters(values[0]);
063            }
064            else
065            {
066                // ensure that escape characters in all list elements are removed
067                List<Object> result = new ArrayList<Object>(values.length);
068                for (int i = 0; i < values.length; i++)
069                {
070                    Object val = handleDelimiters(values[i]);
071                    if (val instanceof Collection)
072                    {
073                        result.addAll((Collection<?>) val);
074                    }
075                    else
076                    {
077                        result.add(val);
078                    }
079                }
080                return result;
081            }
082        }
083    
084        public Iterator<String> getKeys()
085        {
086            // According to the documentation of getParameterMap(), keys are Strings.
087            @SuppressWarnings("unchecked")
088            Map<String, ?> parameterMap = request.getParameterMap();
089            return parameterMap.keySet().iterator();
090        }
091    }