Swing Timer and ActionListener with StackOverflowError-CodePudding

I got a homework that I have tried for a long time and even asked professor about it and still not understand what gone wrong in this code. I have absolutely no idea on how to initialize time ( in SoilTempData constructor ) and not sure on what's wrong with the error so I got no idea on how to fix it. I also can't change codes much because of the Questions to remain the structure of the given code [This is the given Diagram][1]

package Iot;
import java.util.ArrayList;
import javax.swing.Timer;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class SoilTempData implements ActionListener{
    private final int REPORT_ROUND = 1000/100;
    ArrayList<Integer> data;
    private int round;
    private int nextPrintIndex;
    private Timer time;
    private SoilTempIoT iot;
    public SoilTempData(SoilTempIoT iot){
        data = new ArrayList<>(10);
        round = 0;
        nextPrintIndex = 0;
        time = new Timer(100, new SoilTempData(iot));
        iot = new SoilTempIoT();
    }
    public void start() {
        time.start();
    }
    public void actionPerformed(ActionEvent e){
        if(!(round == REPORT_ROUND))
            time.start();
        else
            printStat();
    }
    public void printStat() {
        int min = data.get(nextPrintIndex);
        int max = data.get(nextPrintIndex);
        int sum = 0;
        double average = 0.0;
        double sd = 0.0;
        System.out.println("********** Report Current Data: **********");
        System.out.print("New set of data: ");
        for(int i = nextPrintIndex ; i < data.size() ; i  ) {
            System.out.print(data.get(i)  ", ");
            sum  = data.get(i);
            round  ;
        }
        average = sum/data.size();
        for(int i = nextPrintIndex ; i < data.size() ; i  ) {
            sd  = Math.pow((data.get(i) - average),2);
        }
        System.out.printf("\nTotal records: %d\n",REPORT_ROUND*round);
        System.out.println("Statistics:");
        if(!data.isEmpty()) {
            System.out.printf("Min = %.2f\nMax = %.2f\nAverage = %.2f\nSD = %.2f\n",min,max,average,sd);
        }
        else
            System.out.println("No data to report!");
        nextPrintIndex = REPORT_ROUND*round;
    }
}

and this is SoilTempIoT

package Iot;

import java.awt.event.ActionListener;
import java.util.Random;

public class SoilTempIoT {
    public static final int MIN_TEMP = 10;
    public static final int MAX_TEMP = 60;
    private int temp;
    private Random rand;
    public SoilTempIoT() {
        rand = new Random();
        temp = rand.nextInt(50)   10;
    }
    public int getTemp() {
        int i = rand.nextInt(21) - 10;
        return temp i;
    }
}

and Main class ( which can't change anything because of the Question but incase anyone want to take a look at it )

package Iot;
import javax.swing.JOptionPane;

public class SoilTempDataTest {
    public static void main(String[] args) {
        SoilTempData sensor = new SoilTempData(new SoilTempIoT());
        sensor.printStat();
        sensor.start();
        JOptionPane.showMessageDialog(null, "Quit?");
        System.exit(0);
    }
}

If my question isn't good in any way please tell me I will improve overtime.

Edit : I also need to do it so that SoilTempData read data from SoilTempIoT 100ms and every 1000ms it will print out the Stat. [1]: https://i.stack.imgur.com/VDefv.png

CodePudding user response：

   public SoilTempData(SoilTempIoT iot){
       data = new ArrayList<>(10);
       round = 0;
       nextPrintIndex = 0;
       time = new Timer(100, new SoilTempData(iot));
       iot = new SoilTempIoT();
   }

When you initialize time, you create another instance. That calls the same constructor, which initializes time, which creates another instance, etc.

Just use time = new Timer(100, this);