Question

Scanner scanner = new Scanner(system.in);
String input = new String();

while(!input.equalsIgnoreCase("stop")) {
input = scanner.nextLine();
}

Why is this not working? The loop lasts forever. I have used this method a million times before and now it wont work.

EDIT**

Okay I am using JGrasp (as this is what my professor wants us to use)
and when I tried this in netbeans it worked fine…

EDIT2**

First of all I am not sure whether or not this is the problem but in my code I had something like this towards the beginning of main
Scanner scanner = new Scanner(file);
And later on something like this
scanner = new Scanner(System.in);
and that is where the previous code snippet starts off. So first of all I changed this by having main call a new method for the area where I needed the while loop with string checking. And I also reformatted the loop:

Scanner scanner = new Scanner(System.in);
    String input = new String();

    while(!input.contains("stop")) {
        System.out.print("Enter an option: ");
        input = scanner.nextLine();
    }

And now it works fine.

EDIT3**

So I tried the original format inside the new method and it also works perfectly. I believe now that it has something to do with how I had a scanner for the file and then reused that reference for a new scanner object with System.in. I am not 100% on that, but moving the while loop to a method of its own and not keeping it in main worked, so I feel like it has something to do with that.

Answer 1

Perhaps you should be checking that the Scanner has something left to parse?

while(scanner.hasNextLine() && !input.equalsIgnoreCase("stop")) {
    input = scanner.nextLine();
}