    001    package org.apache.turbine.util;
    002
    003
    004    /*
    005     * Licensed to the Apache Software Foundation (ASF) under one
    006     * or more contributor license agreements.  See the NOTICE file
    007     * distributed with this work for additional information
    008     * regarding copyright ownership.  The ASF licenses this file
    009     * to you under the Apache License, Version 2.0 (the
    010     * "License"); you may not use this file except in compliance
    011     * with the License.  You may obtain a copy of the License at
    012     *
    013     *   http://www.apache.org/licenses/LICENSE-2.0
    014     *
    015     * Unless required by applicable law or agreed to in writing,
    016     * software distributed under the License is distributed on an
    017     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    018     * KIND, either express or implied.  See the License for the
    019     * specific language governing permissions and limitations
    020     * under the License.
    021     */
    022
    023
    024    import java.util.StringTokenizer;
    025
    026    import javax.servlet.ServletConfig;
    027    import javax.servlet.ServletContext;
    028
    029    import org.apache.commons.lang.StringUtils;
    030    import org.apache.turbine.Turbine;
    031
    032    /**
    033     * This is where common Servlet manipulation routines should go.
    034     *
    035     * @author <a href="mailto:gonzalo.diethelm@sonda.com">Gonzalo Diethelm</a>
    036     * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
    037     * @version $Id: ServletUtils.java 1073174 2011-02-21 22:18:45Z tv $
    038     */
    039    public class ServletUtils
    040    {
    041        /**
    042         * Expands a string that points to a relative path or path list,
    043         * leaving it as an absolute path based on the servlet context.
    044         * It will return null if the text is empty or the config object
    045         * is null.
    046         *
    047         * @param config The ServletConfig.
    048         * @param text The String containing a path or path list.
    049         * @return A String with the expanded path or path list.
    050         */
    051        public static String expandRelative(ServletConfig config,
    052                                            String text)
    053        {
    054            if (StringUtils.isEmpty(text))
    055            {
    056                return text;
    057            }
    058
    059            if (config == null)
    060            {
    061                return null;
    062            }
    063
    064            // attempt to make it relative
    065            if (!text.startsWith("/") && !text.startsWith("./")
    066                    && !text.startsWith("\\") && !text.startsWith(".\\"))
    067            {
    068                StringBuffer sb = new StringBuffer();
    069                sb.append("./");
    070                sb.append(text);
    071                text = sb.toString();
    072            }
    073
    074            ServletContext context = config.getServletContext();
    075            String base = context.getRealPath("/");
    076
    077            base = (StringUtils.isEmpty(base))
    078                ? config.getInitParameter(Turbine.BASEDIR_KEY)
    079                : base;
    080
    081            if (StringUtils.isEmpty(base))
    082            {
    083                return text;
    084            }
    085
    086            String separator = System.getProperty("path.separator");
    087
    088            StringTokenizer tokenizer = new StringTokenizer(text,
    089                    separator);
    090            StringBuffer buffer = new StringBuffer();
    091            while (tokenizer.hasMoreTokens())
    092            {
    093                buffer.append(base).append(tokenizer.nextToken());
    094                if (tokenizer.hasMoreTokens())
    095                {
    096                    buffer.append(separator);
    097                }
    098            }
    099            return buffer.toString();
    100        }
    101    }