/*
    * Copyright 2007-2008 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.core.lifecycle;
  
  import java.util.LinkedList;
  import java.util.List;
  
  import org.kuali.rice.core.lifecycle.Lifecycle;
  
  public abstract class BaseCompositeLifecycle extends BaseLifecycle {
  
  	private static final org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(BaseCompositeLifecycle.class);
  
  	private List<Lifecycle> lifecycles;
  
  	protected abstract List<Lifecycle> loadLifecycles() throws Exception;
  
  	@Override
  	public void start() throws Exception {
  	    this.lifecycles = loadLifecycles();
  		for (Lifecycle lifecycle : this.lifecycles) {
  			lifecycle.start();
  		}
  		super.start();
  	}
  
  	@Override
  	public void stop() throws Exception {
  		for (Lifecycle lifecycle : reverseLifecycles()) {
  			try {
  				lifecycle.stop();
  			} catch (Throwable t) {
  				LOG.error("Failed to stop Lifecycle: " + lifecycle.getClass().getName(), t);
  			}
  		}
  		super.stop();
  	}
  
  	private List<Lifecycle> reverseLifecycles() {
  		LinkedList<Lifecycle> reversed = new LinkedList<Lifecycle>();
  		for (Lifecycle lifecycle : this.lifecycles) {
  			reversed.addFirst(lifecycle);
  		}
  		return reversed;
  	}
  
  }