package org.apache.ojb.broker.util;
   
   /* 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 java.util.Map;
  
  public final class IdentityMapFactory
  {
  	private static boolean HAS_JDK_IDENTITY_MAP = true;
  	private static final String CLASS_NAME = "java.util.IdentityHashMap";
  	private static Class JDK_IDENTITY_MAP;
  
  	static
  	{
  		try
  		{
  			JDK_IDENTITY_MAP = ClassHelper.getClassLoader().loadClass(CLASS_NAME);
  		}
  		catch (ClassNotFoundException e)
  		{
  			HAS_JDK_IDENTITY_MAP = false;
  		}
  	}
  	
  	private IdentityMapFactory() {}
  
  	public static Map getIdentityMap()
  	{
  		Map retval = null;
  		if (HAS_JDK_IDENTITY_MAP)
  		{
  			try
  			{
  				retval = (Map) JDK_IDENTITY_MAP.newInstance();
  			}
  			catch (InstantiationException e)
  			{
  				HAS_JDK_IDENTITY_MAP = false;
  			}
  			catch (IllegalAccessException e)
  			{
  				HAS_JDK_IDENTITY_MAP = false;
  			}
  		}
  		if (!HAS_JDK_IDENTITY_MAP)
  		{
  			retval = new org.apache.ojb.broker.util.IdentityHashMap();
  		}
  		return retval;
  	}
  }