Problem with if then else statement

[Scott M Summers]

Hello,
I am having an issue with my if/then/else statement for one of my methods. The method is supposed to take the user input of a character between 'A' and 'Z' (or 'a' and
'z') and return the character to the variable c. If a character other than 'A' thru 'Z' is submitted, it needs to inform the user and loop back. I think my only issue with my code is with the parameter of the if statement.

  public static String getChar(char min, char max){
        getChar(); //Call getChar() method.
        /*Checking parameters*/
        if(c == ??????){
            return c;
        }
        else{
            System.out.println("Invalid input, please enter a character "
                    + "between A and Z: ");
            getChar(min,max);
        }
        return c;

[Tushar Goel]

char are like int. You can check ascii value of the corresponding char and then do as required

[Scott M Summers]

Looking at the ASCII Table, A is 65, Z is 90, a is 97, and z is 122.
Based on how I would do an if statement for an int, this is what I come up with (which is not correct)

if(c >=65 && c <=90 && c >=97 && c <=122){

Where am I going wrong?

[Paweł Baczyński]

First of all, I would use char literals (like 'a') instead of numbers.
Second, you need a character that is between 'a' and 'z' OR between 'A' and 'Z'. Your code says something different.

[Scott M Summers]

Paweł Baczyński, is this what you are saying?

if(c >='a' && c<='z' && c>='A' && c<='Z') {

And in my code (in my main method) I ask for a Character between A and Z, I just need to be case sensitive.

[Paweł Baczyński]

You replaced int literals with char literals correctly. Now you need to fix the other thing I mentioned.

[Scott M Summers]

This is what I have, I am still having an issue with my if statement in my getChar(min,max) method [line 28 of code]:

import java.util.Scanner; // Scanner is in java.util
public class UserInput {
        static String string; //Variable string for the getString() method.
        static String c; //Variable c for the getChar() method.
        static int intValue; //Variable intValue for the getInt() method.
        static double d; //Variable d for the getDouble() method.
    
    //Start of main method.
    public static void main(String [] args){
        /* Request character input between A and Z, call 
         * getChar(char min, char max) method, and display input. */
        System.out.println("Enter a character between A and Z: ");
        getChar('a','z');
        System.out.println("You entered the character " + c);
    }
    //Character method with no parameters.
    public static String getChar(){
        Scanner input = new Scanner(System.in);
        c = input.next(); //User input for the character
        return c; //Returns user input
    }
    //Character method with parameters.
    public static String getChar(char min, char max){
        getChar(); //Call getChar() method.
        /*Checking parameters*/
        if(c >='a' && c<='z' && c>='A' && c<='Z') {
            return c;
        }
        else{
            System.out.println("Invalid input, please enter a character "
                    + "between A and Z: ");
            getChar(min,max);
        }
        return c;
    }

[Paweł Baczyński]

The condition should be true if
c is equal or greater than 'a' and c is equal or less than 'z' OR c is equal or greater than 'A' and c is equal or less than 'Z'.

Now read your code (the if condition) out loud.

Also, your method getChar(char min, char max) takes two parameters but then ignores them.

[Scott M Summers]

Are you saying its supposed to be => & =< ?

if(c =>'a' && c=<'z' && c=>'A' && c=<'Z'){

[Paweł Baczyński]

No.

You need:
c is equal or greater than 'a' and c is equal or less than 'z' OR c is equal or greater than 'A' and c is equal or less than 'Z'

Your code says:
c is equal or greater than 'a' and c is equal or less than 'z' AND c is equal or greater than 'A' and c is equal or less than 'Z'

[Scott M Summers]

I believe this is what you are saying

if(c >='a' && c<='z' || c>='A' && c<='Z'){

[Paweł Baczyński]

You are right.

[Scott M Summers]

With

if(c >='a' && c<='z' || c>='A' && c<='Z'){

I get an error still:

"bad operand types for binary operator '>='
first type: String
second type: char

bad operand types for binary operator '<='
first type: String
second type: char

bad operand types for binary operator '>='
first type: String
second type: char

bad operand types for binary operator '<='
first type: String
second type: char"

[Paweł Baczyński]

That means c is a String. You should declare c as a char.

By the way, c should be a local variable inside a method where you need it, not a static variable.
The same is true for the rest of your static variables.
You should always declare variables in the minimal possible scope.

You said that in your comments. If c is a variable c for the getChar() method let it be declared in the getChar() method.

[Scott M Summers]

Thank you for your help on that. Changing my variable, c, to a char, and my methods from String to char solved those problems.
But now I have a new problem. Line #4 and Line #8.
I use c.charAt(0) to take the first character if a String typed in (since I am requesting a char), but with this I am now getting errors.

Line 4's error is: char cannot be dereferenced
Line 8's error is: incompatible types: String cannot be converted to char

    public static void main(String [] args){
        System.out.println("Enter any character: ");
        getChar();
        System.out.println("You entered the character " + c.charAt(0));
    }
    public static char getChar(){
        Scanner input = new Scanner(System.in);
        c = input.next(); //User input for the character
        return c; //Returns user input
    }

[Paweł Baczyński]

Char is a primitive type. You can not execute any method on it.

[Scott M Summers]

I have them as static variables because I am using each of them in two methods, a method with no parameters, and a method with parameters. Same variable. Am I not correct in keeping them static?

[Paweł Baczyński]

You are not correct keeping them declared as class variables. They should be declared inside methods.

[Scott M Summers]

But if I have a variable that I need to use in two methods, as a local variable in one method, I cannot use that variable in both, correct?

[Campbell Ritchie]

The more fields you have in the class, the more opportunity there is for things to go wrong.
Consider passing the local variable as a parameter to the other method.