gnu.io.CommPortEnumerator Maven / Gradle / Ivy
/*-------------------------------------------------------------------------
| RXTX License v 2.1 - LGPL v 2.1 + Linking Over Controlled Interface.
| RXTX is a native interface to serial ports in java.
| Copyright 1997-2007 by Trent Jarvi [email protected] and others who
| actually wrote it. See individual source files for more information.
|
| A copy of the LGPL v 2.1 may be found at
| http://www.gnu.org/licenses/lgpl.txt on March 4th 2007. A copy is
| here for your convenience.
|
| This library is free software; you can redistribute it and/or
| modify it under the terms of the GNU Lesser General Public
| License as published by the Free Software Foundation; either
| version 2.1 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
| Lesser General Public License for more details.
|
| An executable that contains no derivative of any portion of RXTX, but
| is designed to work with RXTX by being dynamically linked with it,
| is considered a "work that uses the Library" subject to the terms and
| conditions of the GNU Lesser General Public License.
|
| The following has been added to the RXTX License to remove
| any confusion about linking to RXTX. We want to allow in part what
| section 5, paragraph 2 of the LGPL does not permit in the special
| case of linking over a controlled interface. The intent is to add a
| Java Specification Request or standards body defined interface in the
| future as another exception but one is not currently available.
|
| http://www.fsf.org/licenses/gpl-faq.html#LinkingOverControlledInterface
|
| As a special exception, the copyright holders of RXTX give you
| permission to link RXTX with independent modules that communicate with
| RXTX solely through the Sun Microsytems CommAPI interface version 2,
| regardless of the license terms of these independent modules, and to copy
| and distribute the resulting combined work under terms of your choice,
| provided that every copy of the combined work is accompanied by a complete
| copy of the source code of RXTX (the version of RXTX used to produce the
| combined work), being distributed under the terms of the GNU Lesser General
| Public License plus this exception. An independent module is a
| module which is not derived from or based on RXTX.
|
| Note that people who make modified versions of RXTX are not obligated
| to grant this special exception for their modified versions; it is
| their choice whether to do so. The GNU Lesser General Public License
| gives permission to release a modified version without this exception; this
| exception also makes it possible to release a modified version which
| carries forward this exception.
|
| You should have received a copy of the GNU Lesser 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
| All trademarks belong to their respective owners.
--------------------------------------------------------------------------*/
package gnu.io;
import java.util.Enumeration;
/**
* @author Trent Jarvi
* @version %I%, %G%
* @since JDK1.0
*/
@SuppressWarnings("unchecked")
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;
}
}
}