串行数据事件侦听器Java [英] Serial Data Event Listener Java
问题描述
如果有人可以指出我正确的方向，我将非常感激。
I would be really grateful if someone could point me in the right direction
如果没有收到数据，我将如何触发被调用的事件串行通讯示例如下？
How would i go about triggering an event that is called when no data is received from the serial communication example below?
谢谢，
玛丽亚。
Thank you, Maria.
public void connect(String portName) throws Exception {
CommPortIdentifier portIdentifier = CommPortIdentifier.getPortIdentifier(portName);
if (portIdentifier.isCurrentlyOwned()) {
System.out.println("Error: Port is currently in use");
} else {
CommPort commPort = portIdentifier.open(this.getClass().getName(),
2000);
if (commPort instanceof SerialPort) {
SerialPort serialPort = (SerialPort) commPort;
serialPort.setSerialPortParams(9600, SerialPort.DATABITS_8,
SerialPort.STOPBITS_1, SerialPort.PARITY_NONE);
InputStream in = serialPort.getInputStream();
OutputStream out = serialPort.getOutputStream();
theSerialWriter = new SerialWriter(this, out);
new Thread(theSerialWriter).start();
serialPort.addEventListener(new SerialReader(this, in));
serialPort.notifyOnDataAvailable(true);
} else {
System.out.println("Error: Only serial ports are handled by this example.");
}
}
}
public void serialEvent(SerialPortEvent arg0) {
int data;
// boolean setFlagDoorLock = false ;
// if(arg0= 1){}
try {
int len = 0;
while ((data = in.read()) > -1) {
if (data == '\n') {
break;
}
buffer[len++] = (byte) data;
asHexStr = DatatypeConverter.printHexBinary(buffer);
if (asHexStr.contains("FB1")) {
// Thread.sleep(1000);
ActivateSystem = true;
if ((asHexStr.contains("FB1") && (ActivateSystem == true))) {
ActivateSystem = false;
asHexStr = "";
} else {
System.out.println("Here2");
}
}
}
} catch (IOException e) {
e.printStackTrace();
System.exit(-1);
}
System.out.println("Received");
}
}
public static class SerialWriter implements Runnable {
OutputStream out;
SerialPortConnector main = null;
public SerialWriter(SerialPortConnector twoWaySerialComm,
OutputStream out) {
main = twoWaySerialComm;
this.out = out;
}
public void send(String stringToSend) {
try {
int intToSend = Integer.parseInt(stringToSend);
this.out.write(intToSend);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void run() {
try {
int c = 0;
Thread.sleep(1000);
if (asHexStr == "") {
System.out.println("Here");
// ActivateSystem = false;
}
}
// catch ( IOException e )
catch (Exception e) {
e.printStackTrace();
System.exit(-1);
}
}
}
public static void main(String[] args) {
try {
(new SerialPortConnector()).connect("COM12");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
推荐答案
您已在注释中说明了这一点：
You have stated this in a comment:
我需要检测到ID已经停止， b $ b超时（或者没有连续检测到id几次）然后
发送一个url调用（我已经有一个类发送呼叫） - 这应该
只发送一次而它正在读取ID，但是另一个url调用
应该再次发送一次只有
I need to be able to detect that the id has stopped and after a timeout(or after it not detecting the id a few times in a row) then send a url call( i already have a class to send the call)-this should only be sent once.while it is reading the id however another url call should be sent again-once only
如果我明白这个权利那么你需要检查两个不同的东西：
If I understand this right then you need to check for two different things:
- 设备在发送ID时停止。
- 设备发送一些空的ID。
这个要求是一种棘手的问题。正如我已经说过，如果没有数据到达串行端口，那么没有串口事件将被触发。我想您可以使用计时器来检查超时并使用计数器来注册到达的空ID号。这样的东西：
This requirement is a kind of tricky. As I've said if no data arrives to the serial port then no serial port event will be fired. I think you can use a Timer to check the timeout and use a counter to register the number of empty ID's arrived. Something like this:
int numberOfEmptyIds = 0;
int maxNumberOfAttempts = 5;
boolean urlSent = false;
long timeoutInMillis = 10000; // let's say 10000 millis, equivalent to 10 seconds
Timer timer = null;
public void connect(String portName) throws Exception {
...
scheduleTimer();
}
public void serialEvent(SerialPortEvent evt) {
if(evt.getEventType() == SerialPortEvent.DATA_AVAILABLE) {
try {
while(in.read(buffer) > -1) {
String asHexStr = DatatypeConverter.printHexBinary(buffer);
if(asHexStr.contains("FB1")) {
scheduleTimer();
numberOfEmptyIds = 0;
} else {
numberOfEmtyIds++;
if(numberOfEmptyIds == maxNumberOfAttempts && !urlSent) {
// send the url here
}
}
}
} catch (IOException ex) {
// Log the exception here
}
}
}
private void scheduleTimer() {
if(timer != null) {
timer.cancel();
}
timer = new Timer("Timeout");
TimerTask task = new TimerTask() {
@Override
public void run() {
if(!urlSent) {
// send the url here
}
}
};
timer.schedule(task, timeoutInMillis);
}
我不知道这是否是 / em> 你需要什么，但希望它是有帮助的。
I don't know if this is exactly what you need but hope it be helpful.
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