import com.pi4j.io.serial.SerialPortException; //导入依赖的package包/类
/**
 * Returns true if the connection to the serial port is successful
 * Also returns true if the output is disabled so that debugging will work
 * 
 * @return connected status
 */
public boolean connect() {
	if (LedTable_Settings.enableTableOutput) {
		try {
		     // open the default serial port provided on the GPIO header
		    serial.open(comPort, baud);
		    Thread.sleep(1000); //connect time
		    connected = true;
		    return true;
		} 
		catch(InterruptedException e) {
			System.out.println("Thread Interrupted: " + e);
			connected = false;
			return false;
		} 
		catch(SerialPortException ex) {
			System.out.println("SERIAL SETUP FAILED : " + ex);
			connected = false;
			return false;
		}
	} else { //table output not enabled, use debug
		connected = true;
	}
	return connected;
}
 

import com.pi4j.io.serial.SerialPortException; //导入依赖的package包/类
/**
 * Construct the BrickPiSerialTransmitter with blocking queues for messaging
 * @param timeout The timeout in millisecond to wait before retrying to send and receive data
 * @throws RaspoidSerialException in case of trouble when opening serial communications with the brick pi
 */
public BrickPiSerialTransmitter(int timeout) {
    this.timeout = timeout;
    try {
        serial = SerialFactory.createInstance();
        serial.open(Serial.DEFAULT_COM_PORT, BAUD_RATE);
        serial.setMonitorInterval(SERIAL_MONITOR_RATE);
    } catch (SerialPortException e) {
        throw new RaspoidSerialException("The transmitter was unable to open the serial channel", e);
    }
}
 

import com.pi4j.io.serial.SerialPortException; //导入依赖的package包/类
@Override
public SerialConnection openConnection(int baud) throws IOException {
    try {
        return new PiSerialConnection(port, baud);
    } catch (SerialPortException serialPortException) {
        throw new IOException(serialPortException);
    } catch (InterruptedException interruptedException) {
        throw new IOException(interruptedException);
    }
}
 

import com.pi4j.io.serial.SerialPortException; //导入依赖的package包/类
private ArduinoFactory(){
  try {
SERIAL.open(PORT, 38400);
  } catch(SerialPortException | IOException ex) {
      System.out.println(" ==>> SERIAL SETUP FAILED : " + ex.getMessage());
  }
 }