rxtxSerial library multiple serial port listener registration and handling

[Kujtim Hyseni]

Hello All, I am using rxtxSerial library (import gnu.io.*;) for my bridge application. Th example provided in the library's web site with nulltest.java employs only one serial port. It is powerful since it is threaded and detects incomming/outgoing streams. However, I would like to bridge between servers so multiple ports will be employed. Do you heave any suggestion how to obtain it. The null test code is presented as follows.

// derived from SUN's examples in the javax.comm package
import java.io.*;
import java.util.*;
//import javax.comm.*; // for SUN's serial/parallel port libraries
import gnu.io.*; // for rxtxSerial library

public class nulltest implements Runnable, SerialPortEventListener {
static CommPortIdentifier portId;
static CommPortIdentifier saveportId;
static Enumeration portList;
InputStream inputStream;
SerialPort serialPort;
Thread readThread;

static String messageString = "AT";
static OutputStream outputStream;
static boolean outputBufferEmptyFlag = false;

public static void main(String[] args) {
boolean portFound = false;
String defaultPort;

  // determine the name of the serial port on several operating systems
  String osname = System.getProperty("os.name","").toLowerCase();
  if ( osname.startsWith("windows") ) {
     // windows
     defaultPort = "COM5";
  } else if (osname.startsWith("linux")) {
     // linux
    defaultPort = "/dev/ttyS0";
  } else if ( osname.startsWith("mac") ) {
     // mac
     defaultPort = "????";
  } else {
     System.out.println("Sorry, your operating system is not supported");
     return;
  }
      
  if (args.length > 0) {
     defaultPort = args\[0\];
  } 

  System.out.println("Set default port to "+defaultPort);
  
	// parse ports and if the default port is found, initialized the reader
  portList = CommPortIdentifier.getPortIdentifiers();
  while (portList.hasMoreElements()) {
     portId = (CommPortIdentifier) portList.nextElement();
     if (portId.getPortType() == CommPortIdentifier.PORT\_SERIAL) {
        if (portId.getName().equals(defaultPort)) {
           System.out.println("Found port: "+defaultPort);
           portFound = true;
           // init reader thread
           nulltest reader = new nulltest();