How to check if a given character is a number/letter in Java?

The Character class is a subclass of Object class and it wraps a value of the primitive type char in an object. An object of type Character contains a single field whose type is char. We can check whether the given character in a string is a number/letter by using isDigit() method of Character class. The isDigit() method is a static method and determines if the specified character is a digit.

Example

public class CharacterIsNumberOrDigitTest {
   public static void main(String[] args) {
      String str = "Tutorials123";
      for(int i=0; i < str.length(); i++) {
         Boolean flag = Character.isDigit(str.charAt(i));
         if(flag) {
            System.out.println("'"+ str.charAt(i)+"' is a number");
         }
         else {
            System.out.println("'"+ str.charAt(i)+"' is a letter");
         }
      }
   }
}

Output

'T' is a letter
'u' is a letter
't' is a letter
'o' is a letter
'r' is a letter
'i' is a letter
'a' is a letter
'l' is a letter
's' is a letter
'1' is a number
'2' is a number
'3' is a number

Raja

Published on 07-Aug-2019 11:54:53

• Related Questions & Answers
• How to check if a character in a string is a letter in Python?
• Check if input is a number or letter in JavaScript?
• Java Program for check if a given number is Fibonacci number?
• How to check if a given number is a Fibonacci number in Python Program ?
• Check if a given number is Pronic in C++
• Python Program for How to check if a given number is a Fibonacci number?
• C# Program to check if a character is a whitespace character
• Check if a given string is a valid number in C++
• Check if a given string is a valid number in Python
• Python program to check if the given number is a Disarium Number
• Check if a given mobile number is fancy in C++
• Check whether the Unicode character is a lowercase letter in C#
• Python program to check if a given string is number Palindrome
• Check if a character is alphanumeric in Arduino
• Check if a character is printable in Arduino