Java Program to remove all white spaces from a String.

The replaceAll() method of the String class replaces each substring of this string that matches the given regular expression with the given replacement. You can remove white spaces from a string by replacing " " with "".

Example

 Live Demo

public class DuplicateCharacters {
   public static void main(String[] args){
      String str = "Hello how are you";
      str = str.replaceAll(" ", "");
      System.out.println(str);
   }
}

Output

Hellohowareyou