Check whether a character is an alphabet or not in Java

Understanding Alphabets

An alphabet is any letter from A to Z (both uppercase and lowercase). Any other character is not considered an alphabet.

We will explore three different methods to check whether a character is an alphabet or not in Java.

Method 1: Using if-else

This method checks if the character falls within the range of alphabets.

import java.util.Scanner;

public class AlphabetCheck {
    public static void checkAlphabet(char ch) {
        if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')) {
            System.out.println(ch + " is an alphabet");
        } else {
            System.out.println(ch + " is not an alphabet");
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter a character: ");
        char ch = scanner.next().charAt(0);
        checkAlphabet(ch);
        scanner.close();
    }
}
            

Method 2: Using ASCII Values

This method checks the ASCII values of the character.

import java.util.Scanner;

public class AlphabetCheckASCII {
    public static void checkAlphabet(char ch) {
        if ((ch >= 65 && ch <= 90) || (ch >= 97 && ch <= 122)) {
            System.out.println(ch + " is an alphabet");
        } else {
            System.out.println(ch + " is not an alphabet");
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter a character: ");
        char ch = scanner.next().charAt(0);
        checkAlphabet(ch);
        scanner.close();
    }
}
            

Method 3: Using a Function

This method defines a function to check if a character is an alphabet.

import java.util.Scanner;

public class AlphabetCheckFunction {
    public static boolean isAlphabet(char ch) {
        return ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z'));
    }

    public static void checkAlphabet(char ch) {
        if (isAlphabet(ch)) {
            System.out.println(ch + " is an alphabet");
        } else {
            System.out.println(ch + " is not an alphabet");
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter a character: ");
        char ch = scanner.next().charAt(0);
        checkAlphabet(ch);
        scanner.close();
    }
}