Java - Deploying RXTX

Question

I am on Windows Seven 64-bit. I wrote a little application that uses RXTX to communication through serial port. I used the rxtxSerial.dll for Windows 64-bit and it works pretty well on both Eclispe and NetBeans.

At the root of the project, I placed RXTXComm.jar and rxtxSerial.dll.

The problem appears when I want to deploy the application. I used the Export function on Eclipse or I accessed the bin/ folder from NetBeans. I placed again RXTXComm.jar and rxtxSerial.dll at the root of the folders but when I execute the Application.jar, RXTX doesn't seem working. The scan seems to stay stuck whereas it shouldn't last more than a second.

[Sorry, I "need at least 10 reputation to post images."]

I tried all the suggestions I found on the internet:

• installing the dlls and RXTXComm.jar in the JRE folder
• placing the dlls in Windows32 folder
• tried all the different export options of Export from Eclipse

I must be missing something. Has anyone already been successful in deploying RXTX for Windows 32/64bit and MAC? Could you describe what you did and what is necessary to do so?

Please find below the piece of code executing when scanning for ports:

private void scanButtonAction()
{
    if(scanState == ST_FREE)
    {
        scanState = ST_SCANNING;
        redrawComponents();
        scan = new Thread(new ScanPorts());
        scan.start();
    }
}

// Thread run to scan the ports
private class ScanPorts implements Runnable {
    public void run()
    {
        try
        {
            UARTConnection connection = new UARTConnection();

            // listPort() is a long blocking call
            String[][] list = connection.listPorts();

            // Display the ports in the ComboBox
            comboBoxModel.removeAllElements();

            if(list.length == 0)    comboBoxModel.addElement( new Item(-1, "No port scanned", "" ) );
            else
            {
                for(int i = 0; i < list.length; i++)
                {
                    // Id, Description (user's display), PortName (for serial connection)
                    comboBoxModel.addElement( new Item(i, list[i][1], list[i][0]) );
                }

                // To select the first item of the list. Necessary with custom Rendered
                portNumberBox.setSelectedIndex(0);
            }

            scanState = ST_FREE;
            redrawComponents();

            // The connect button is enabled only after a first scan
            connectButton.setEnabled(true);
        }
        catch(Exception ex)
        {
            scanState = ST_FREE;
            redrawComponents();
        }
    }
}

public class UARTConnection {

public UARTConnection()
{

}

public String[][] listPorts() throws Exception
{
    Enumeration<CommPortIdentifier> portEnum = CommPortIdentifier.getPortIdentifiers();
    Enumeration<CommPortIdentifier> tmpPortEnum = portEnum;

    ArrayList<String[]> list = new ArrayList<String[]>();

    int i = 0;
    while ( portEnum.hasMoreElements() ) 
    {
        String port[] = new String[2];
        CommPortIdentifier portIdentifier = portEnum.nextElement();
        System.out.println(portIdentifier.getName()  +  " - " +  getPortTypeName(portIdentifier.getPortType()));

        port[0] = portIdentifier.getName();
        port[1] = portIdentifier.getName()  +  " - " +  getPortTypeName(portIdentifier.getPortType());

        list.add(port);

        i++;
    }

    String listOfPort[][] = new String[list.size()][2];
    for(i = 0; i < list.size(); i++)
    {
        String[] port = list.get(i);
        listOfPort[i][0] = port[0];
        listOfPort[i][1] = port[1];
    }

    return listOfPort;
}

private String getPortTypeName ( int portType )
{
    switch ( portType )
    {
        case CommPortIdentifier.PORT_I2C:
            return "I2C";
        case CommPortIdentifier.PORT_PARALLEL:
            return "Parallel";
        case CommPortIdentifier.PORT_RAW:
            return "Raw";
        case CommPortIdentifier.PORT_RS485:
            return "RS485";
        case CommPortIdentifier.PORT_SERIAL:
            return "Serial";
        default:
            return "unknown type";
    }
}   
}

Thank you for your help.

Answer 1

I found the solution, for those it might help.

When running the application from Eclipse or NetBean, the app is running in 64-bit. Hence, I used the 64bit rxtxSerial.dll. It was working properly.

But I realized when running the compiled .jar outside of the IDE, the Windows process list was displaying javaw.exe *32 for the application. For some reason I ignore, the compiled .jar was in 32bit. Hence, the driver required was for Windows 32bit, not the 64bit. It works well from now on.

Note: in order to be able to work on my MAC, I had to compile the application in Java 1.6 (not 1.7) and to provide the MAC driver of course.