Error while running program using RXTX

Question

I am using RXTX(gnu.io.*;) for serial port communiction im my application, I have downloaded the library and added the supporting files as follows:

1. Copied rxtxParallel.dll and rxtxSerial.dll inside C:\Program Files\Java\jdk1.8.0_25\jre\bin
2. Copied RXTXcomm.jar inside C:\Program Files\Java\jdk1.8.0_25\jre\lib\ext

I am trying to execute my program mentioned below:

import gnu.io.*;
import java.io.*;
import java.util.*;

public class SimpleWrite implements Runnable, SerialPortEventListener {

    public void run() {
    }
    static Enumeration portList;
    static CommPortIdentifier portId;
    static String messageString = "AAA";
    static char ch = '"';
    static String dest = ch + "XXXXXXXXXXX" + ch;  // 11 Digit Mobile Number.
    static InputStream inputStream;
    static SerialPort serialPort;
    static OutputStream outputStream;

public void serialEvent(SerialPortEvent event) {
    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: {

            BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
            String line = "";
            try {

                while ((line = reader.readLine()) != null) {
                    System.out.println(line);
                }
            } catch (IOException e) {
                System.err.println("Error while reading Port " + e);
            }
            break;

        }
    } //switch
}

public SimpleWrite(SerialPort serial) {
    try {
        inputStream = serial.getInputStream();
        try {
            serial.addEventListener(this);
        } catch (TooManyListenersException e) {
            System.out.println("Exception in Adding Listener" + e);
        }
        serial.notifyOnDataAvailable(true);

    } catch (Exception ex) {
        System.out.println("Exception in getting InputStream" + ex);
    }

}

public static void main(String[] args) {
    String line1 = "AT+CSMS=1\r\n";
    String line2 = "AT+CMGS=" + dest + "\r\n";
    String line3 = messageString + "\r\n";

    portList = CommPortIdentifier.getPortIdentifiers();

    while (portList.hasMoreElements()) {
        portId = (CommPortIdentifier) portList.nextElement();
        if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
            if (portId.getName().equals("COM3")) {
                System.out.println("SMS Sending....Port Found");
                try {
                    serialPort = (SerialPort) portId.open("SimpleWriteApp", 2000);
                    SimpleWrite wr = new SimpleWrite(serialPort);

                } catch (PortInUseException e) {
                    System.out.println("Port In Use " + e);
                }
                try {
                    outputStream = serialPort.getOutputStream();
                } catch (IOException e) {
                    System.out.println("Error writing to output stream " + e);
                }
                try {
                    serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
                } catch (UnsupportedCommOperationException e) {
                }
                try {
                    outputStream.write(line1.getBytes());
                    outputStream.write(line1.getBytes());
                    outputStream.write(line2.getBytes());
                    outputStream.write(line3.getBytes());
                    outputStream.write(26);
                    outputStream.flush();
                } catch (Exception e) {
                    System.out.println("Error writing message " + e);
                }
            }
        }
    }
}

/**
 * show text in the text window
 *
 * @param Text text string to show on the display
 */
public static void showText(String Text) {
    System.out.println(Text);
  }
}

But I am getting the error as follows while running my application as follows:

C:\>javac SimpleWrite.java

C:\>java SimpleWrite 
java.lang.UnsatisfiedLinkError: no rxtxSerial in java.library.path thrown while
loading gnu.io.RXTXCommDriver
Exception in thread "Thread-0" java.lang.UnsatisfiedLinkError: no rxtxSerial in
java.library.path
        at java.lang.ClassLoader.loadLibrary(Unknown Source)
        at java.lang.Runtime.loadLibrary0(Unknown Source)
        at java.lang.System.loadLibrary(Unknown Source)
        at gnu.io.CommPortIdentifier.<clinit>(CommPortIdentifier.java:83)
        at SerialConnection.openConnection(SerialConnection.java:71)
        at Sender.send(Sender.java:46)
        at SMSClient.run(SMSClient.java:39)
        at java.lang.Thread.run(Unknown Source)

I have checked but all the solutions is showing is regarded with IDEs. How can solve this? Please guide me I am new to this!

Answer 1

If you are running the program from IDE, make sure that your project's java platform is set to the one you copied library, i,e, C:\Program Files\Java\jdk1.8.0_25\

Because, IDE comes with default java platform & when you run the project it uses default Java platform.

You can change which platform to use for your project under project's properties dialog.