String to double

Question

I want the user to enter a random mathematical expression in a string variable and then I want to convert it to double data type.
I tried explicit conversion but it didn't work.
what to do?

Answer 1

import java.util.Scanner;
public class Program {
public static void main(String[] args) {

Scanner scn = new Scanner(System.in);
String x = scn.next();

try{
Double y = Double.valueOf(x);
System.out.println(y);
} catch (NumberFormatException e) {
System.err.println("input only numbers!");
}
}
}

Answer 2

thanks I'll try that