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

The Character class is a subclass of the Object class, which wraps the value of the original type char in an object. An object of type Character contains a single field of type char. We can use isDigit() method of Character class to check if a given character in a string is a number/letter. The isDigit() method is a static method used to determine whether 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++) {
         <strong>Boolean </strong>flag = <strong>Character.isDigit(str.charAt(i))</strong>;
         if(flag) {
            System.out.println("&#39;"+ str.charAt(i)+"&#39; is a number");
         }
         else {
            System.out.println("&#39;"+ str.charAt(i)+"&#39; 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

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