Check if a specific format of string is between specific parameters

Question

I have gone through several post and could not find why my code is not working ok.

I have to ask the user to input a string through console with the following format.

[CapitalLeter][Number]

Where the letter must be A,B,C,D,E or F, and the number between 1 and 6.

This is my code.

        while ((x.length() != 2) || (x.charAt(0)>='F' && x.charAt(0)<='A') || (Character.getNumericValue(x.charAt(1))>=6 && Character.getNumericValue(x.charAt(1))<=1))
{
        System.out.println(msg);
        x = (new Scanner(System.in)).nextLine();
    }

If I give it for example 3F it will accept it, and its wrong.

Can you help me?

Thanks

Answer 1

since OP answered himself I'll just copy-paste a commend made by @lospejos, which I think is a way better solution than the one proposed by OP (just for future generations sake)

if (matchesFormat(input)) {
    /* ok */ 
} else { 
    /* not ok */
}

with a helper method

boolean matchesFormat(String input) {
    return input.matches("[A-F][1-6]");
}

Answer 2

I was using && when I should be using ||, fixed.

Thanks