/*-------------------------------------------------------------------------
|   rxtx is a native interface to serial ports in java.
|   Copyright 1997-2003 by Trent Jarvi taj@www.linux.org.uk
|
|   This library is free software; you can redistribute it and/or
|   modify it under the terms of the GNU Library General Public
|   License as published by the Free Software Foundation; either
|   version 2 of the License, or (at your option) any later version.
|
|   This library 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
|   Library General Public License for more details.
|
|   You should have received a copy of the GNU Library General Public
|   License along with this library; if not, write to the Free
|   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
--------------------------------------------------------------------------*/
package  gnu.io;

import java.util.Enumeration;

/**
* @author Trent Jarvi
* @version %I%, %G%
* @since JDK1.0
*/


class CommPortEnumerator implements Enumeration
{
	private CommPortIdentifier index;
	private final static boolean debug = false;
	static
	{
		if (debug)
			System.out.println("CommPortEnumerator:{}");
	}

	CommPortEnumerator()
	{
	}
/*------------------------------------------------------------------------------
        nextElement()
        accept:
        perform:
        return:
        exceptions:
        comments:
------------------------------------------------------------------------------*/
	public Object nextElement()
	{
		if(debug) System.out.println("CommPortEnumerator:nextElement()");
		synchronized (CommPortIdentifier.Sync)
		{
			if(index != null) index = index.next;
			else index=CommPortIdentifier.CommPortIndex;
			return(index);
		}
	}
/*------------------------------------------------------------------------------
        hasMoreElements()
        accept:
        perform:
        return:
        exceptions:
        comments:
------------------------------------------------------------------------------*/
	public boolean hasMoreElements()
	{
		if(debug) System.out.println("CommPortEnumerator:hasMoreElements() " + CommPortIdentifier.CommPortIndex == null ? false : true );
		synchronized (CommPortIdentifier.Sync)
		{
			if(index != null) return index.next == null ? false : true;
			else return CommPortIdentifier.CommPortIndex == null ?
				false : true;
		}
	}
}