我正在尝试连接到Serial Port …但是一旦我第一次打开串行端口.我不能再打开它,我试着申请.这是我的代码：

public static void main(String[] args) {

portList = CommPortIdentifier.getPortIdentifiers();

while (portList.hasMoreElements()) {

portId = (CommPortIdentifier) portList.nextElement();

if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {

if (portId.getName().equals("COM1")) {

try {

serialPort = (SerialPort)

portId.open("SimpleWriteApp", 2000);

} catch (PortInUseException e) {}

try {

outputStream = serialPort.getOutputStream();

} catch (IOException e) {}

try {

serialPort.setSerialPortParams(9600,

SerialPort.DATABITS_8,

SerialPort.STOPBITS_1,

SerialPort.PARITY_NONE);

} catch (UnsupportedCommOperationException e) {}

try {

outputStream.write(messageString.getBytes());

} catch (IOException e) {}

}

}

}

}

我想关闭该端口,以便我可以将它用于其他任务.