How to check if a String has only alphabets

You can use Java regular expressions to check if a String has only alphabets as follows:

package demo;public class StringDemo {public static void main(String[] args) {String str = "HelloWorld";String regex = "^[a-zA-Z]+$";boolean matches = str.matches(regex);System.out.println(matches);}}

 

The above code will print true when you run it. If you change the String str to have any other characters like numbers or special characters, it will print false.

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