How to have Scanner and Timer run at the same time

I am trying to make a rotating password program, the issue I am running into is when the program asks for the digits of the password, the timer will stop. I think I could separate the program into 2 operational files and a main file, I would not like to go this route though.

Does anyone have any ideas on how I can solve this problem?

'''

if(i == 10)
        {
            System.out.println("New Passcode: ");
            i = -1;
            d = 0;
            passCode.clear();
            Attempt.clear();
            for(int j = 1; j <= 9;j++)
      {
         Random rand = new Random();
         int upperbound = 10;
         int keycode = rand.nextInt(upperbound);
         passCode.add(keycode);
         x++;
      }
         System.out.println(passCode);
         
         //This is the password input
         
               for(int f = 1; f <= 9;f++)
      {
         d++;
         System.out.println("Input one digit at a time; You are on digit " + d);
         int passAtt = input.nextInt();
         Attempt.add(passAtt);
      }
      System.out.println(Attempt);
        }
        else{
            i++;
            System.out.println("Timer: " + i + " Seconds");
        }
        while(x >= 1)
        {
            if(passCode.equals(Attempt))
        {
            System.out.println(" ");
            System.out.println("ACCESS GRANTED");
            System.exit(1);
        }
        }
    }
'''

Looks like you are using an integer to mark the seconds. Instead, create a variable to store the start time. Then subtract that from the current time whenever you want to get the elapsed time. For example, use System.currentTimeMillis()

Here's a simple class you can use to keep track of the elapsed time:

class StopWatch
{
	protected long startTime;
	protected long endTime;
	protected boolean running = false;
	
	public void start()
	{
		startTime = System.currentTimeMillis();
		running = true;
	}
	public void stop()
	{
		endTime = System.currentTimeMillis();
		running = false;
	}
	public double getElapsedSeconds()
	{
		if (running) {
			return (System.currentTimeMillis() - startTime) / 1000.0;
		}
		else  {
			return (endTime - startTime) / 1000.0;
		}
	}
}

And example usage:

StopWatch st = new StopWatch();
st.start();
Thread.sleep(1000);  // Simulate long-running operation
System.out.println(st.getElapsedSeconds());
Thread.sleep(5500);  // Another long-running operation
st.stop();
System.out.println(st.getElapsedSeconds());;

And the output will be something like:
<pre>
1.0
6.514
</pre>