/*

  *   SONEWS News Server

  *   see AUTHORS for the list of contributors

  *

  *   This program is free software: you can redistribute it and/or modify

  *   it under the terms of the GNU General Public License as published by

  *   the Free Software Foundation, either version 3 of the License, or

  *   (at your option) any later version.

  *

  *   This program is distributed in the hope that it will be useful,

  *   but WITHOUT ANY WARRANTY; without even the implied warranty of

  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  *   GNU General Public License for more details.

  *

  *   You should have received a copy of the GNU General Public License

  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.

  */

 package org.sonews.storage;

 /**

  * Provides access to a storage backend.

  * @author Christian Lins

  * @since sonews/1.0

  */

 public final class StorageManager {

 	private static StorageProvider provider;

 	public static Storage current() throws StorageBackendException {

 		synchronized (StorageManager.class) {

 			if (provider == null) {

 				return null;

 			} else {

 				return provider.storage(Thread.currentThread());

 			}

 		}

 	}

 	public static StorageProvider loadProvider(String pluginClassName) {

 		try {

 			Class<?> clazz = Class.forName(pluginClassName);

 			Object inst = clazz.newInstance();

 			return (StorageProvider)inst;

 		} catch (Exception ex) {

 			System.err.println(ex);

 			return null;

 		}

 	}

 	/**

 	 * Sets the current storage provider.

 	 * @param provider

 	 */

 	public static void enableProvider(StorageProvider provider) {

 		synchronized (StorageManager.class) {

 			if (StorageManager.provider != null) {

 				disableProvider();

 			}

 			StorageManager.provider = provider;

 		}

 	}

 	/**

 	 * Disables the current provider.

 	 */

 	public static void disableProvider() {

 		synchronized (StorageManager.class) {

 			provider = null;

 		}

 	}

 }