Check If a Character is An Alphabet Character or Not in Java

Exercise:

Write a Java Program to check whether a character is an alphabet character or not.

1. Check using if..else statement.

Click Here to View the Solution!
public class AlphabetChecker {
 
    public static void main(String[] args) {
 
        char ch = '-';
 
        if( (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z'))
            System.out.println(ch + " is an alphabet character.");
        else
            System.out.println(ch + " is not an alphabet character.");
    }
}
Click Here to View the Output!
- is not an alphabet character.
Click Here to View the Explanation!
  • This program is used for finding that whether the character stored in a variable is an alphabet or not by using the if…else statement and display the result on the screen.
  • A character variable ch is used for storing the value in the form of an ASCII value of a character instead of the character itself.
  • It is to be noted that the range of the lowercase alphabets in ASCII is from 97 to 122 while that of uppercase alphabets is from 65 to 90. This means that 97 is a and 122 is z while 65 is A and 90 is Z.
  • The character “-” is stored in ch. It is then compared to the ASCII values ranging between a to z and A to Z. That is if on comparison, the ASCII value of the character variable ch matches any ASCII value between 97 to 122 and 65 to 90, it will be considered an alphabet.
  •  Since the ASCII value of “-” does not match any ASCII value of the alphabets, the result “- is not an alphabet character” will be displayed on the screen.

2. Check using Ternary Operator.

Click Here to View the Solution!
public class Alphabet {
 
    public static void main(String[] args) {
 
        char ch = 'b';
        
 String output = (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')
                ? ch + " is an alphabet character."
                : ch + " is not an alphabet character.";
        
        System.out.println(output);
    }
} 
Click Here to View the Output!
b is an alphabet character.
Click Here to View the Explanation!
  • This program performs the process of the identification of an alphabet by using a ternary operator and displays the result on the screen.
  • This program is similar to the above program, except that instead of using the if…else statement, this program uses the ternary operator (?:), which functions in the same way as an if…else statement.
  • If the character “b” is stored in the character variable ch, then on comparison, the program will print the result “b is an alphabet character”.

3. Check using isAlphabetic() Method.

Click Here to View the Solution!
public class AlphabetChecker {
    public static void main(String[] args) {
        char ch = 'h';
        // built in method to check if ch is an alphabet
        if (Character.isAlphabetic(ch)) {
            System.out.println(ch + " is an alphabet character.");
        }
        else {
            System.out.println(ch + " is not an alphabet character.");
        }
    }
} 
Click Here to View the Output!
h is an alphabet character.
Click Here to View the Explanation!
  • This program identifies an alphabet stored in a character variable by using a Java method, isAlphabetic() and the if…else statement and displays the result.
  • A character “h” is stored in the character variable ch. The isAlphabetic() method is stated in the if statement as an expression of a condition which belong to the Character Class of Java. The expression used is (Character.isAlphabetic(ch)).
  • The isAlphabetic() method functions in a simple way. It returns true if the variable it reads contains an alphabet else returns false and prints the output.
  • Since “h” is an alphabet, the isAlphabetic() method will return true and print “h is an alphabet character”.