Thread: Get user input of letters w/ numerical values, and straight numbers.

I don't know why I am having such a hard time figuring this out, but here's my seemingly simple situation (Try and figure out what I'm trying to make ).

I got 12 variables, 2 of each equal the same numerical value, and a variable known as hex which I have made a String currently; which I have demonstrated as such:

String hex;
int A,a = 10;
int B,b = 11;
int C,c = 12;
int D,d = 13;
int E,e = 14;
int F,f = 15;

Now I am prompting the user to enter either one of the several listed variables (they will already know which are allowed to enter) and/or any one-digit number. (1) If 694 is entered, it should be read as '6' and '9' and '4', not as a three digit number. I don't want the data to be mixed up into one big number value either, I need each number to be accepted as is and not added in.

(2) Thing is, I'm not exactly sure how to accept both kinds of data while maintaining the variables values, and without an error. (3) I need the data to be displayed back as is, just like how the user entered it. So if the user entered AD6F9, I need it to be displayed like that but still have A = 10, D = 13, 6 = 6, F = 15, and 9 = 9.

This is what I have for displaying the output, which isn't working the way I like right now.

System.out.print("Enter Hexadecimal: ");
            hex = in.nextLine();
 
            int hexInt = Integer.parseInt(hex);
            System.out.println(hex);

*Sigh*, well I am trying to add a feature to a converter script of mine that also accepts Hexadecimal input and outputs it in decimal, binary, and text. There's not really any code that is causing trouble, it's more like coming up with code to solve my (1), (2), & (3). I guess I'll tackle this one at a time.

Lets start with (2), I'm not sure how to accept those a,A,b,B,c,C,d,D,e,E, variables that are declared and initialized, into an input that's accepted as numbers. Because when the user is prompt, and they enter a letter from those list of variables, its accepted as a letter regardless. I can't do in.next(); because it will take it as a String, and I can't seem to do in.nextInt() because it takes it only sees it as a letter and returns an error. You see what I mean?

In brief: Can I get user input to accept both letters and numbers without error?

Here is how I would do it. Get rid of all those variables. Read user input as a String. Iterate over the String one char at a time and use a switch statement.

Originally Posted by Junky

Here is how I would do it. Get rid of all those variables. Read user input as a String. Iterate over the String one char at a time and use a switch statement.

Might have to go that route, though I am not familiar with a "switch statement".

Originally Posted by Norm

What do you intend to do with the variables: a,A, ... f,F?
Will they be declared as final and their values never changed?

How will you use those variables to convert what the user enters to hexidecimal?

The data in the variables will just be used to compute an answer from hex to decimal, binary, and char, and vice versa. Though I will need it to be printed later too, the variables themselves that is, to the terminal screen. I never thought of declaring them as a final.. but no, their values will never change.

I'm going to use them in some sort of algorithm that is commonly or uncommonly used by people to figure out hex on paper.

---Now that I'm thinking about it, I might have to just use if and else if statements to give me what I want. If it seems not much else can be done.