/*
 * Copyright (c) 2006 Stiftung Deutsches Elektronen-Synchroton,
 * Member of the Helmholtz Association, (DESY), HAMBURG, GERMANY.
 *
 * THIS SOFTWARE IS PROVIDED UNDER THIS LICENSE ON AN "../AS IS" BASIS.
 * WITHOUT WARRANTY OF ANY KIND, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE AND
 * NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
 * FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. SHOULD THE SOFTWARE PROVE DEFECTIVE
 * IN ANY RESPECT, THE USER ASSUMES THE COST OF ANY NECESSARY SERVICING, REPAIR OR
 * CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE.
 * NO USE OF ANY SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER THIS DISCLAIMER.
 * DESY HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
 * OR MODIFICATIONS.
 * THE FULL LICENSE SPECIFYING FOR THE SOFTWARE THE REDISTRIBUTION, MODIFICATION,
 * USAGE AND OTHER RIGHTS AND OBLIGATIONS IS INCLUDED WITH THE DISTRIBUTION OF THIS
 * PROJECT IN THE FILE LICENSE.HTML. IF THE LICENSE IS NOT INCLUDED YOU MAY FIND A COPY
 * AT HTTP://WWW.DESY.DE/LEGAL/LICENSE.HTM
 */

package org.epics.css.dal.directory;

import java.util.Hashtable;

import javax.naming.Context;
import javax.naming.NamingException;
import javax.naming.spi.InitialContextFactory;


/**
 * This is initial dir context for CSS. Takes care that only one initial context is creted in single JVM.
 *
 * <p>
 * In order this factory to be loaded
 * in JNDI jndi.properties file must be provided in classpath  containing
 * following line:
 * <code>java.naming.factory.initial=org.epics.css.dal.directory.InitialContextFactoryImpl</code>.
 * </p>
 *
 * @author Igor Kriznar (igor.kriznarATcosylab.com)
 */
public class InitialContextFactoryImpl implements InitialContextFactory
{
	private static InitialDirContextImpl ctx;

	/**
	 * Defautlt constructor.
	 */
	public InitialContextFactoryImpl()
	{
		super();
	}

	/* (non-Javadoc)
	 * @see javax.naming.spi.InitialContextFactory#getInitialContext(java.util.Hashtable)
	 */
	@Override
	public Context getInitialContext(Hashtable<?, ?> environment)
		throws NamingException
	{
		if (ctx == null) {
			ctx = new InitialDirContextImpl(environment);
		}

		return ctx;
	}
}

/* __oOo__ */