RE:Serial communication using java

Question

Hello,
First of all, I want to make clear thatI did not double post it as previously I posted it in Networking section..But I was told that I have not posted it at appropirate place....thats wht I am posting here.
I am a newbie in Java.I have started with Netbeans.I have designed a interface using Netbeans.It has 5 texboxes and two buttons named "Start" and "Stop".
I want to receive data from the serial port and display the data in text boxes.I want when I press Start button, then it should start listening to the serial port .If adat is present on serial port, then it must receive it and displayin the text boxes.when I press Stop button, then it should stop receiving data as well close connection.
can please anyone help me on this?
I would be highly thankful for this.
Regards,
Jass

Answer 1

Hello All,
I am using the javax.comm for serial communication using serial to usb converter at port COM4(I check using device manager.).Beside that I have also added the option in the programming to look into other COMs also.I have placed "comm.jar " and "javax.properties" into jdk\lib\ext and "win32.dll" into jdk\bin.
But I am getting the following output:
Wed Dec 24 02:23:43 EST 2008: COM4 null
Serial port List is  javax.comm.CommPortEnumerator@1a46e30
Serial port ID  is null
BUILD SUCCESSFUL (total time: 0 seconds)
The code Is as follows:
import java.io.*;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.comm.*;
import java.util.*;
public class serialport implements Runnable, SerialPortEventListener
    static CommPortIdentifier portId, portId1;
    public SerialPort serialPort;
    public OutputStream outputStream;
    public InputStream inputStream;
    Thread readThread;
    static Enumeration portList;
     static String TimeStamp;
    public static void main(String args[])     
    {try {
          portId1 = CommPortIdentifier.getPortIdentifier("COM4");
          }catch(Exception e) {
      TimeStamp = new java.util.Date().toString();
      System.out.println(TimeStamp + ": COM4 " + portId1);}
           portList = CommPortIdentifier.getPortIdentifiers();
           System.out.println("Serial port List is  "+portList+"\n");
           portId = (CommPortIdentifier) portList.nextElement();
          System.out.println("Serial port ID  is "+portId+"\n");
       while (portList.hasMoreElements()) {
          portId = (CommPortIdentifier) portList.nextElement();
          if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
            if (portId.getName().equals("COM3")) {
                 System.out.println("Serial port COM3 is found\n");
            serialport Port = new serialport();
            else if (portId.getName().equals("COM4")) {
                 System.out.println("Serial port COM4 is found\n");
            serialport Port = new serialport();
            else if (portId.getName().equals("COM6")) {
                 System.out.println("Serial port COM6 is found\n");
            serialport Port = new serialport();
            else if (portId.getName().equals("COM7")) {
                 System.out.println("Serial port COM7 is found\n");
            serialport Port = new serialport();
            else if (portId.getName().equals("COM5")) {
                 System.out.println("Serial port COM8 is found\n");
            serialport Port = new serialport();
  public serialport()
    try {
      serialPort = (SerialPort) portId.open("MainClassApp", 2000);
    } catch (PortInUseException e) {
              System.out.println("Port is owned by another application \nor port cannot be opened\n");
    try {
      inputStream = serialPort.getInputStream();
    } catch (IOException e) {
         System.out.println("IOstream for port is not available\n");}
    try {
      serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1,SerialPort.PARITY_NONE);
    } catch (UnsupportedCommOperationException e) {
         System.out.println("Serial port is not properly configured\n");}
    try {
      serialPort.addEventListener(this);
    } catch (TooManyListenersException e) {
         e.printStackTrace();}
    serialPort.notifyOnDataAvailable(true);
    readThread = new Thread(this);
    readThread.start();
    public void run() {
       try {
         Thread.sleep(2000);
           } catch (InterruptedException e) {      e.printStackTrace();}
    public void serialEvent(SerialPortEvent event) {
         Runtime rt = Runtime.getRuntime() ;
         Process p;
    switch (event.getEventType()) {
    case SerialPortEvent.BI:
    case SerialPortEvent.OE:
    case SerialPortEvent.FE:
    case SerialPortEvent.PE:
    case SerialPortEvent.CD:
    case SerialPortEvent.CTS:
    case SerialPortEvent.DSR:
    case SerialPortEvent.RI:
    case SerialPortEvent.OUTPUT_BUFFER_EMPTY:
      break;
    case SerialPortEvent.DATA_AVAILABLE:
      byte[] readBuffer = new byte[1];
      try {
        while (inputStream.available() > 0)
               int numBytes = inputStream.read(readBuffer);
               System.out.print(new String(readBuffer));
                break;
        System.out.print(new String(readBuffer));
            } catch (Exception e) {
           e.printStackTrace();}
      break;}  }  }Kindly help........I really wanna to know where is the error???
Thanks
Edited by: jass11 on Dec 23, 2008 11:39 PM
Edited by: jass11 on Dec 23, 2008 11:51 PM