http://www.sparetimelabs.com/purejavacomm/purejavacomm.php: PureJavaComm is an Application Programmin Interface (API) for accessing serial ports from Java. PureJavaComm aims to be a drop-in replacement for Sun's (now Oracle) abandoned JavaComm and an easier to deploy alternative to RXTX.
  • Kustaa Nyholm 
package purejavacomm;

public interface CommPortOwnershipListener {
	public static final int PORT_OWNED = 1;
	public static final int PORT_OWNERSHIP_REQUESTED = 3;
	public static final int PORT_UNOWNED = 2;

	public void ownershipChange(int type);
}