I am working a much more complex version of this (with vehicle moving in both X and Y directions)
I made this example to get ideas on better ways to accomplish this.
- I have a vehicle moving in the X direction at a speed (24.5872 mps)
- I am simulating this by incrementing the X value every 100 ms using an executor (To keep its X position more accurate and real time)
- After each second, I send a message to another process with the xMin and xMax values of the line I just covered
- The other process will respond with a JMS message (usually instantly) telling me to stop if there was an "Pothole" in the previous X area (Message callback msg to a linkedblockingqueue).
The problem I have is with the "usually instantly" part. If I do not get a response quick enough, I think it will throw off the whole timing of my algorithm. What is a better way to handle this situation?
Here is some basic code of what I am trying to do:
public class Mover implements MessageHandler {
private static final long CAR_UPDATE_RATE_IN_MS = 100;
private static double currX = 0;
private static double CONSTANT_SPEED_IN_MPS = 24.5872; // 55 mph
private static double increment = CONSTANT_SPEED_IN_MPS / (1000 / CAR_UPDATE_RATE_IN_MS);
static LinkedBlockingQueue<BaseMessage> messageQueue = new LinkedBlockingQueue<BaseMessage>(); // ms
private static int incrementor = 0;
public static void main(String[] args) {
startMoverExecutor();
}
private static void startMoverExecutor() {
ScheduledExecutorService mover = Executors.newSingleThreadScheduledExecutor();
mover.scheduleAtFixedRate((new Runnable() {
@Override
public void run() {
currX = incrementor * increment;
if (incrementor % (1000 / CAR_UPDATE_RATE_IN_MS) == 0) {
System.out.println(currX);
sendMessage(currX - CONSTANT_SPEED_IN_MPS, currX);
// do something
try {
messageQueue.poll(1000, TimeUnit.MILLISECONDS);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
incrementor++;
}
}), 0, CAR_UPDATE_RATE_IN_MS, TimeUnit.MILLISECONDS);
}
@Override
public void handleMessage(BaseMessage msg) {
messageQueue.add(msg);
}
protected static void sendMessage(double firstX, double secondX) {
// sendMessage here
}
}