001    // Copyright 2004, 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.hivemind.util;
016    
017    import org.apache.hivemind.HiveMind;
018    
019    /**
020     * A collection of utilities for handling qualified and unqualified ids.
021     *
022     * @author Howard Lewis Ship
023     */
024    public class IdUtils
025    {
026    
027        /**
028         * Returns a fully qualfied id.  If the id contains a '.', then it
029         * is returned unchanged.  Otherwise, the module's id is prefixed (with a 
030         * seperator '.') and returned;
031         */
032        public static String qualify(String moduleId, String id)
033        {
034            if (id.indexOf('.') > 0)
035                return id;
036    
037            return moduleId + "." + id;
038        }
039    
040        /**
041         * Qualifies a list of interceptor service ids provided for an interceptor
042         * contribution.  The special value "*" is not qualified.
043         */
044        public static String qualifyList(String sourceModuleId, String list)
045        {
046            if (HiveMind.isBlank(list) || list.equals("*"))
047                return list;
048    
049            String[] items = StringUtils.split(list);
050    
051            for (int i = 0; i < items.length; i++)
052                items[i] = qualify(sourceModuleId, items[i]);
053    
054            return StringUtils.join(items, ',');
055        }
056        
057        /**
058         * Removes the module name from a fully qualified id
059         */
060        public static String stripModule(String id)
061        {
062            int lastPoint = id.lastIndexOf('.');
063            if (lastPoint > 0)
064                return id.substring(lastPoint + 1, id.length());
065            else return id;
066        }
067    
068        /**
069         * Extracts the module name from a fully qualified id
070         * Returns null if id contains no module
071         */
072        public static String extractModule(String id)
073        {
074            int lastPoint = id.lastIndexOf('.');
075            if (lastPoint > 0)
076                return id.substring(0, lastPoint);
077            else return null;
078        }
079    
080    }