001    /**
002     * Copyright (c) 2000-2012 Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.util.bridges.mvc;
016    
017    import com.liferay.portal.kernel.log.Log;
018    import com.liferay.portal.kernel.log.LogFactoryUtil;
019    import com.liferay.portal.kernel.util.InstanceFactory;
020    import com.liferay.portal.kernel.util.StringBundler;
021    import com.liferay.portal.kernel.util.StringPool;
022    import com.liferay.portal.kernel.util.StringUtil;
023    
024    import java.util.ArrayList;
025    import java.util.List;
026    import java.util.Map;
027    import java.util.concurrent.ConcurrentHashMap;
028    
029    import javax.portlet.PortletRequest;
030    import javax.portlet.PortletResponse;
031    
032    /**
033     * @author Michael C. Han
034     */
035    public class ActionCommandCache {
036    
037            public static final String ACTION_PACKAGE_NAME = "action.package.prefix";
038    
039            public static final ActionCommand EMPTY = new ActionCommand() {
040    
041                    public boolean processCommand(
042                            PortletRequest portletRequest, PortletResponse portletResponse) {
043    
044                            return false;
045                    }
046    
047            };
048    
049            public ActionCommandCache(String packagePrefix) {
050                    if (!packagePrefix.endsWith(StringPool.PERIOD)) {
051                            packagePrefix = packagePrefix + StringPool.PERIOD;
052                    }
053    
054                    _packagePrefix = packagePrefix;
055            }
056    
057            public ActionCommand getActionCommand(String actionCommandName) {
058                    String className = null;
059    
060                    try {
061                            ActionCommand actionCommand = _actionCommandCache.get(
062                                    actionCommandName);
063    
064                            if (actionCommand != null) {
065                                    return actionCommand;
066                            }
067    
068                            StringBundler sb = new StringBundler(4);
069    
070                            sb.append(_packagePrefix);
071                            sb.append(Character.toUpperCase(actionCommandName.charAt(0)));
072                            sb.append(actionCommandName.substring(1));
073                            sb.append(_ACTION_COMMAND_POSTFIX);
074    
075                            className = sb.toString();
076    
077                            actionCommand = (ActionCommand)InstanceFactory.newInstance(
078                                    className);
079    
080                            _actionCommandCache.put(actionCommandName, actionCommand);
081    
082                            return actionCommand;
083                    }
084                    catch (Exception e) {
085                            if (_log.isWarnEnabled()) {
086                                    _log.warn("Unable to instantiate ActionCommand " + className);
087                            }
088    
089                            _actionCommandCache.put(actionCommandName, EMPTY);
090    
091                            return EMPTY;
092                    }
093            }
094    
095            public List<ActionCommand> getActionCommandChain(
096                    String actionCommandChain) {
097    
098                    List<ActionCommand> actionCommands = _actionCommandChainCache.get(
099                            actionCommandChain);
100    
101                    if (actionCommands != null) {
102                            return actionCommands;
103                    }
104    
105                    actionCommands = new ArrayList<ActionCommand>();
106    
107                    String[] actionCommandNames = StringUtil.split(actionCommandChain);
108    
109                    for (String actionCommandName : actionCommandNames) {
110                            ActionCommand actionCommand = getActionCommand(actionCommandName);
111    
112                            if (actionCommand != EMPTY) {
113                                    actionCommands.add(actionCommand);
114                            }
115                            else {
116                                    if (_log.isWarnEnabled()) {
117                                            _log.warn(
118                                                    "Unable to find ActionCommand " + actionCommandChain);
119                                    }
120                            }
121                    }
122    
123                    _actionCommandChainCache.put(actionCommandChain, actionCommands);
124    
125                    return actionCommands;
126            }
127    
128            public boolean isEmpty() {
129                    return _actionCommandCache.isEmpty();
130            }
131    
132            private static final String _ACTION_COMMAND_POSTFIX = "ActionCommand";
133    
134            private static Log _log = LogFactoryUtil.getLog(ActionCommandCache.class);
135    
136            private Map<String, ActionCommand> _actionCommandCache =
137                    new ConcurrentHashMap<String, ActionCommand>();
138            private Map<String, List<ActionCommand>> _actionCommandChainCache =
139                    new ConcurrentHashMap<String, List<ActionCommand>>();
140            private String _packagePrefix;
141    
142    }