用无符号字节的Java发票打印CommPortIdentifier发出

import gnu.io.CommPortIdentifier;
import gnu.io.NoSuchPortException;
import gnu.io.PortInUseException;
import gnu.io.SerialPort;
import gnu.io.UnsupportedCommOperationException;
import java.io.IOException;
import java.io.OutputStream;

public class SimpleWrite {
    static CommPortIdentifier portId;
    static SerialPort serialPort;
    static OutputStream outputStream;

        public static void print(String messageString){
        try {
            portId = CommPortIdentifier.getPortIdentifier( \"COM1\");
            serialPort = (SerialPort) portId.open(\"SimpleWrite\", 2000);
            outputStream = serialPort.getOutputStream();
            serialPort.setSerialPortParams( 9600,
                                            SerialPort.DATABITS_8,
                                            SerialPort.STOPBITS_1,
                                            SerialPort.PARITY_NONE);
            outputStream.write(messageString.getBytes());
            serialPort.close();
        }catch (IOException e) {                        System.out.println(e.getMessage());
        }catch (PortInUseException e) {                 System.out.println(e.getMessage());
        }catch (UnsupportedCommOperationException e) {  System.out.println(e.getMessage());
        }catch (NoSuchPortException e) {                System.out.println(e.getMessage());}
    }

    public static void main(String[] args) throws IOException{
        print(\"Hello , world \\n\\r\");
    }
}