/*

  * Copyright 2006-2011 The Kuali Foundation

  *

  * Licensed under the Educational Community License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  * http://www.opensource.org/licenses/ecl2.php

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.kuali.rice.kew.plugin;

 import java.util.ArrayList;

 import java.util.Collections;

 import java.util.List;

 import javax.xml.namespace.QName;

 import org.kuali.rice.core.api.config.CoreConfigHelper;

 import org.kuali.rice.core.api.resourceloader.ResourceLoader;

 import org.kuali.rice.core.api.resourceloader.ResourceLoaderContainer;

 /**

  * A base class for {@link PluginRegistry} implementations.  Is essentially a ResourceLoader 

  * implementation that ensures plugins are the only ResourceLoaders used.  Also maintains

  * information about the PluginEnvironments of the loaded plugins in this registry.

  * 

  * @see Plugin

  * @see PluginEnvironment

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public abstract class BasePluginRegistry extends ResourceLoaderContainer implements PluginRegistry {

         private List<PluginEnvironment> pluginEnvironments = Collections.synchronizedList(new ArrayList<PluginEnvironment>());

         public BasePluginRegistry() {

                 super(new QName(CoreConfigHelper.getApplicationId(), ResourceLoader.PLUGIN_REGISTRY_LOADER_NAME));

         }

         public BasePluginRegistry(QName name) {

                 super(name);

         }

     public PluginEnvironment getPluginEnvironment(String pluginName) {

             for (PluginEnvironment environment : pluginEnvironments) {

                     if (environment.getPluginName().equals(pluginName)) {

                             return environment;

                     }

             }

             return null;

     }

         public void addPluginEnvironment(PluginEnvironment pluginEnvironment) {

                 // chances are that this plugin has already been added to the resource loader

                 if (pluginEnvironment.getPlugin() != null && !containsResourceLoader(pluginEnvironment.getPlugin())) {

                         addResourceLoader(pluginEnvironment.getPlugin());

                 }

                 pluginEnvironments.add(pluginEnvironment);

         }

         public PluginEnvironment removePluginEnvironment(String pluginName) {

             PluginEnvironment environment = getPluginEnvironment(pluginName);

         if (environment == null) {

             return null;

         }

         if (environment.getPlugin() != null) {

             super.removeResourceLoader(environment.getPlugin().getName());

         }

                 if (!pluginEnvironments.remove(environment)) {

                         return null;

                 }

                 return environment;

         }

         public Plugin getPlugin(QName pluginName) {

                 return (Plugin)getResourceLoader(pluginName);

         }

         public List<QName> getPluginNames() {

                 return super.getResourceLoaderNames();

         }

         public List<PluginEnvironment> getPluginEnvironments() {

                 return Collections.unmodifiableList(pluginEnvironments);

         }

 }