java 打开和关闭串行端口
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/6924516/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
Open and Close Serial Ports
提问by S Gaber
I am trying to connect to a Serial Port... but once I open the Serial Portin the first time. I can't open it again, I've tried to apply. Here is my code:
我正在尝试连接到串行端口......但是一旦我Serial Port第一次打开它。我无法再次打开它，我已尝试申请。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) {}
}
}
}
}
I want to close that port so I can use it for another task.
我想关闭该端口，以便我可以将其用于其他任务。
回答by Manuel Selva
回答by sjpapa
serialPort.close(); works for me. Be careful not to use the port again before closing it, as a lock file is written to the /var/lock Linux directory. In windows something similar I presume. This file has to be deleted before reopening the port. Otherwise a nullPointerException will occur. Closing the port deletes this file.
serialPort.close(); 对我来说有效。注意在关闭之前不要再次使用端口，因为锁文件被写入 /var/lock Linux 目录。在 Windows 中，我认为类似的东西。在重新打开端口之前必须删除此文件。否则将发生 nullPointerException。关闭端口会删除此文件。
