Can you help me improve this code? (Java)

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Java

mathematics

Hello everyone, i am new here so i am sorry if i am posting this in the wrong category. I'm a begginer programmer and i am trying to get better. Right now i am writing a small tool that solves mathematical problems. I would very much appreciate it if you could tell me what i'm doing wrong and how i could improve my code (the tool is working). The project is not finished yet and thus far i have only made a simple calculator. However i intend to build the other features the same way as this simple calculator so any feedback would be nice.

What I have tried:

This is the current code, the reason the whole thing is inside a while loop is because i want the user to be able to use the calculator tool multiple times without having to run the app every time.

import java.util.Scanner;
public class NumberHeron
{
	public static void main(String[] args)
	{
		System.out.println("Choose your prefered tool\n");
		System.out.println("1. Simple Calculator\n");
		Scanner scanner = new Scanner(System.in);
		int tool = scanner.nextInt();
		switch(tool)
		{
			case 1:
		    while(tool == 1)
			{
			try {
			System.out.println("Enter two numbers");
			double numOne = scanner.nextDouble();
			double numTwo = scanner.nextDouble();
			System.out.println("Enter an operation, valid ones are: +, -, *, /");
			System.out.println("Type (q) to exit");
			Scanner s = new Scanner(System.in);
			String operation = s.nextLine();
			if (operation.equals("+"))
			{
				SimpleCalculator simpleCalc = new SimpleCalculator();
				double result = simpleCalc.add(numOne, numTwo);
				System.out.println("The result is " + result);
			}
			else if (operation.equals("-"))
			{
				SimpleCalculator simpleCalc = new SimpleCalculator();
				double result = simpleCalc.substract(numOne, numTwo);
				System.out.println("The result is " + result);
			}
			else if (operation.equals("*"))
			{
				SimpleCalculator simpleCalc = new SimpleCalculator();
				double result = simpleCalc.multiply(numOne, numTwo);
				System.out.println("The result is " + result);
			}
			else if (operation.equals("/"))
			{
				SimpleCalculator simpleCalc = new SimpleCalculator();
				double result = simpleCalc.divide(numOne, numTwo);
				System.out.println("The result is " + result);
			}
			else if (operation.equals("q"))
			{
				break;
			}
		  } catch(Exception ex) { ex.printStackTrace(); break; }
		}
		}
		scanner.close();
	}
}
class SimpleCalculator 
{
	public static double add(double valueOne,double valueTwo)
	{
		double result = valueOne + valueTwo;
		return result;
	}
	public static double substract(double valueOne, double valueTwo)
	{
		double result = valueOne - valueTwo;
		return result;
	}
	public static double multiply(double valueOne, double valueTwo)
	{
		double result = valueOne * valueTwo;
		return result;
	}
	public static double divide(double valueOne, double valueTwo)
	{
		double result = valueOne / valueTwo;
		return result;
	}
}