001    /* 
002        Licensed to the Apache Software Foundation (ASF) under one
003        or more contributor license agreements.  See the NOTICE file
004        distributed with this work for additional information
005        regarding copyright ownership.  The ASF licenses this file
006        to you under the Apache License, Version 2.0 (the
007        "License"); you may not use this file except in compliance
008        with the License.  You may obtain a copy of the License at
009    
010           http://www.apache.org/licenses/LICENSE-2.0
011    
012        Unless required by applicable law or agreed to in writing,
013        software distributed under the License is distributed on an
014        "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015        KIND, either express or implied.  See the License for the
016        specific language governing permissions and limitations
017        under the License.  
018     */
019    package org.apache.wiki.modules;
020    
021    import java.util.Collection;
022    
023    import org.apache.wiki.Release;
024    import org.apache.wiki.WikiEngine;
025    
026    /**
027     *  Superclass for all JSPWiki managers for modules (plugins, etc).
028     */
029    public abstract class ModuleManager
030    {
031    
032        /**
033         * Location of the property-files of plugins.
034         *  (Each plugin should include this property-file in its jar-file)
035         */
036        public static final String PLUGIN_RESOURCE_LOCATION = "ini/jspwiki_module.xml";
037            
038        protected WikiEngine m_engine;
039        
040        private boolean m_loadIncompatibleModules = false;
041        
042        /**
043         *  Constructs the ModuleManager.
044         *  
045         *  @param engine The WikiEngine which owns this manager.
046         */
047        public ModuleManager( WikiEngine engine )
048        {
049            m_engine = engine;
050        }
051        
052        /**
053         *  Returns true, if the given module is compatible with this version of JSPWiki.
054         *  
055         *  @param info The module to check
056         *  @return True, if the module is compatible.
057         */
058        public boolean checkCompatibility( WikiModuleInfo info )
059        {
060            if( !m_loadIncompatibleModules )
061            {
062                String minVersion = info.getMinVersion();
063                String maxVersion = info.getMaxVersion();
064                
065                return Release.isNewerOrEqual( minVersion ) && Release.isOlderOrEqual( maxVersion );
066            }
067            
068            return true;
069        }
070        
071        /**
072         * Returns a collection of modules currently managed by this ModuleManager.  Each
073         * entry is an instance of the WikiModuleInfo class.  This method should return something
074         * which is safe to iterate over, even if the underlying collection changes.
075         * 
076         * @return A Collection of WikiModuleInfo instances.
077         */
078        public abstract Collection modules();
079    }