SensorSimulator.java

import java.util.concurrent.BlockingQueue;
import java.util.Random;
import java.util.Date;

public class SensorSimulator extends Thread {
    private final BlockingQueue<DataRecord> queue;
    private final int intervalMs;
    private volatile boolean running = true;
    private final Random rnd = new Random();

    public SensorSimulator(BlockingQueue<DataRecord> queue, int intervalMs) {
        this.queue = queue;
        this.intervalMs = intervalMs;
    }

    @Override
    public void run() {
        String[] locations = {"Field A", "Field B", "North Plot", "Greenhouse 1"};
        while (running) {
            try {
                // Simulate realistic ranges
                double moisture = 10 + rnd.nextDouble() * 80;       // 10..90%
                double pH = 4.5 + rnd.nextDouble() * 4.5;          // 4.5..9.0
                double temp = 15 + rnd.nextDouble() * 25;          // 15..40 C
                double hum = 20 + rnd.nextDouble() * 70;           // 20..90%
                double light = 100 + rnd.nextDouble() * 900;       // 100..1000 lux
                String loc = locations[rnd.nextInt(locations.length)];

                DataRecord r = new DataRecord(moisture, pH, temp, hum, light, loc, new Date());
                queue.offer(r);

                Thread.sleep(intervalMs);
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
            }
        }
    }

    public void stopSimulator() {
        running = false;
    }
}