Because of an optimization in Slice where it does not attempt to look at characters when the size of the slice would take it off the end of the input, Matcher does not properly report hitting the end of input. The characters must be examined to determine if the slice was matching up to the end of input, or if the slice already failed before reaching the end of input.

import java.util.*;
 
public class Blah {
    static Scanner console = Scanner.create(System.in);
 
    public static void main (String[] args) {
        String str1;
        String str2;
        double x = 0;
        double y = 0;

        console.useDelimiter("\n");
 
        System.out.print("Enter the first string: ");
        str1 = console.nextLine();

        System.out.print("Enter the second string: ");
        str2 = console.nextLine();
 
        System.out.print("Enter x: ");
        x = console.nextDouble(); //read the first number

        System.out.print("Enter y: ");
        y = console.nextDouble(); //read the second number

        System.out.println("str1: " + str1);
        System.out.println("str2: " + str2);
        System.out.printf("x = %5.2f %n", x);
        System.out.printf("y = %5.2f %n", y);
        System.out.println();
    }
}