如何在Java系统中运行comport代码而又不实际在Linux系统中运行

Question

I have a project in java, which is using comport for communication. And using comport 1 and 2 number. But my linux system is not capable to have com-port. I want to run the code and want to listen data send on comport. but when i am running code, it throws error. How should i pursue.

My comport utility code is something like this

import com.fazecast.jSerialComm.SerialPort;

public class ComPortUtil {
private static SerialPort comPort;
private static SerialPort relayPort;

static {
    SerialPort[] serialPorts = SerialPort.getCommPorts();
    comPort = serialPorts[3];
    comPort.setBaudRate(115200);
    comPort.setParity(SerialPort.NO_PARITY);
    comPort.setNumDataBits(8);
    comPort.setNumStopBits(SerialPort.ONE_STOP_BIT);
    relayPort = serialPorts[1];
    relayPort.setBaudRate(115200);
    relayPort.setParity(SerialPort.NO_PARITY);
    relayPort.setNumDataBits(8);
    relayPort.setNumStopBits(SerialPort.ONE_STOP_BIT);
}

public static SerialPort getPOSPort() {
    return comPort;
}

public static SerialPort getRelayPort() {
    return relayPort;
}

}

Answer 1

I had a similar problem, developing a software which needed to read a serial port.

My workstation did not have serials (it was a virtualized machine) so I resorted to create virtual serial ports with com0com .

It can create 2 virtual com port cross-linked (the input of one is the output of the other).

I configured one to be used by my app, and I created a small program using the other to send input for testing the app.

This is an example of a test writing on a virtual COM port, while the application is listening on its crosslinked COM.

static SerialPort commPort = null;

@BeforeClass
public static void setUpClass(){
    commPort = SerialPort.getCommPort("CNCB0");
    commPort.openPort();
}


@Test
public void showControl(){
    shortWait();
    send(commPort, "S421803171");
    // ...
    // A delay of few millis ...
    shortWait();
    String value = lookup("#fldFicheBarcode").queryAs(TextField.class).getText();
    // ...
    assertEquals("S421803171", value);
}

protected static void send(final SerialPort commPort, final String _txt) {
    ForkJoinPool.commonPool().submit(()->{
        final String txt = !_txt.endsWith(CRLF)?_txt+CRLF:_txt;
        byte[] bytes = txt.getBytes();
        int writeBytes = commPort.writeBytes(bytes, bytes.length);
        logger.debug("Written bytes:"+writeBytes);
    }).join();
}