import javax.comm.*;
import java.util.Enumeration;
public class Main {
  public Main() {
  }
  public static void main(String[] args) {
    try {
      Enumeration portList = CommPortIdentifier.getPortIdentifiers();
      while(portList.hasMoreElements()){
        CommPortIdentifier pi = (CommPortIdentifier)portList.nextElement();
        try {
          SerialPort sp = (SerialPort)pi.open("TEST", 5000);
        } catch(PortInUseException piue) {
          System.out.println("Port In Use");
        }
      }
    } catch(Exception e) {
      System.out.println(e.getMessage());
    }
  }
}