package org.apache.ojb.broker.core;

 /* Copyright 2003-2005 The Apache Software Foundation

  *

  * Licensed under the Apache 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.apache.org/licenses/LICENSE-2.0

  *

  * 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.

  */

 import org.apache.ojb.broker.OJBRuntimeException;

 import org.apache.ojb.broker.util.ClassHelper;

 import org.apache.ojb.broker.util.configuration.Configuration;

 import org.apache.ojb.broker.util.configuration.Configurator;

 import org.apache.ojb.broker.util.configuration.impl.OjbConfigurator;

 import org.apache.ojb.broker.util.logging.Logger;

 import org.apache.ojb.broker.util.logging.LoggerFactory;

 /**

  *

  * @author Thomas Mahler

  * @version $Id: PersistenceBrokerFactoryFactory.java,v 1.1 2007-08-24 22:17:35 ewestfal Exp $

  */

 public class PersistenceBrokerFactoryFactory

 {

     private static Logger log = LoggerFactory.getBootLogger();

     private static final String PBF_KEY = "PersistenceBrokerFactoryClass";

     private static PersistenceBrokerFactoryIF singleton = init();

     /**

      * Returns an {@link PersistenceBrokerFactoryIF} instance.

      */

     public static PersistenceBrokerFactoryIF instance()

     {

         return singleton;

     }

     private static PersistenceBrokerFactoryIF init()

     {

         if (log.isDebugEnabled()) log.debug("Instantiate PersistenceBrokerFactory");

         Class pbfClass = null;

         try

         {

             Configurator configurator = OjbConfigurator.getInstance();

             Configuration config = configurator.getConfigurationFor(null);

             pbfClass = config.getClass(PBF_KEY, null);

             if(pbfClass == null)

             {

                 log.error("Creation of PersistenceBrokerFactory (PBF) instance failed, can't get PBF class object");

                 throw new OJBRuntimeException("Property for key '" + PBF_KEY + "' can not be found in properties file");

             }

             PersistenceBrokerFactoryIF result = (PersistenceBrokerFactoryIF) ClassHelper.newInstance(pbfClass);

             configurator.configure(result);

             log.info("PersistencebrokerFactory class instantiated: " + result);

             return result;

         }

         catch (Exception e)

         {

             if(e instanceof OJBRuntimeException)

             {

                 throw (OJBRuntimeException) e;

             }

             else

             {

                 throw new OJBRuntimeException("Error while instantiation of PersistenceBrokerFactory class", e);

             }

         }

     }

 }