Java – Check if String contains only Digits
To check if String contains only digits in Java, call matches() method on the string object and pass the regular
expression "[0-9]+" that matches only if the characters in the given string are digits.
String.matches() with argument as "[0-9]+" returns a boolean value of true if the String contains only
digits, else it returns false.
The syntax to use a String.matches() to check if String contains only digits is
Example – Positive Scenario
In the following program, we will take a string and check if it contains only digits using String.matches() method.
Java Program
Output
Example – Negative Scenario
In the following program, we will take a string containing some alphabets and whitespace characters. When we
How to Check if String contains only Digits in
Java?
String.matches("[0-9]+")
public class Example {
public static void main(String[] args){
String str = "5236841234";
boolean result = str.matches("[0-9]+");
System.out.println("Original String : " + str);
System.out.println("Does string contain only Digits? : " + result);
}
}
Original String : 5236841234
Does string contain only Digits? : true
