Sample program for https://stackoverflow.com/questions/68579674

Scratch.java

import java.util.Scanner;

public class Scratch {

    // Assign multiple double values from System.in 
    // without writing `nextDouble()` more than once.
    public enum DoubleExample {
        A, B, C;
        public final double value;
        private DoubleExample() { value = new Scanner(System.in).nextDouble(); }
    }
    
    // Entry point to demonstrate the example.
    public static void main(String... args) {
        System.out.println(DoubleExample.A.value);
        System.out.println(DoubleExample.B.value);
        System.out.println(DoubleExample.C.value);
    }
}