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
018package org.apache.commons.configuration2.web;
019
020import javax.servlet.ServletRequest;
021import java.util.ArrayList;
022import java.util.Collection;
023import java.util.Iterator;
024import java.util.List;
025import java.util.Map;
026
027/**
028 * A configuration wrapper to read the parameters of a servlet request. This configuration is read only, adding or
029 * removing a property will throw an UnsupportedOperationException.
030 *
031 * @since 1.1
032 */
033public class ServletRequestConfiguration extends BaseWebConfiguration {
034    /** Stores the wrapped request. */
035    protected ServletRequest request;
036
037    /**
038     * Create a ServletRequestConfiguration using the request parameters.
039     *
040     * @param request the servlet request
041     */
042    public ServletRequestConfiguration(final ServletRequest request) {
043        this.request = request;
044    }
045
046    @Override
047    protected Object getPropertyInternal(final String key) {
048        final String[] values = request.getParameterValues(key);
049
050        if (values == null || values.length == 0) {
051            return null;
052        }
053        if (values.length == 1) {
054            return handleDelimiters(values[0]);
055        }
056        // ensure that escape characters in all list elements are removed
057        final List<Object> result = new ArrayList<>(values.length);
058        for (final String value : values) {
059            final Object val = handleDelimiters(value);
060            if (val instanceof Collection) {
061                result.addAll((Collection<?>) val);
062            } else {
063                result.add(val);
064            }
065        }
066        return result;
067    }
068
069    @Override
070    protected Iterator<String> getKeysInternal() {
071        // According to the documentation of getParameterMap(), keys are Strings.
072        final Map<String, ?> parameterMap = request.getParameterMap();
073        return parameterMap.keySet().iterator();
074    }
075}