Java | Removing whitespaces using Regex

Difficulty Level : Basic
Last Updated : 11 Dec, 2018

The following programs demonstrates how to remove the white spaces using matcher.replaceAll(String replacement) method of Util.regex.Pattern class.

The java.util.regex.Matcher.replaceAll(String replacement) method replaces every subsequence of the input sequence that matches the pattern with the given replacement string.

Declaration: public String replaceAll(String replacement)
Parameters: replacement – The replacement string.
Return Value:The string constructed by replacing each matching subsequence by the replacement string, substituting captured subsequences as needed.

// Java program to remove whitespaces from a string
import java.util.regex.Matcher;
import java.util.regex.Pattern;
  
public class GeeksforGeeks {
  
    public static String removeWhite(String s) {
      
        // Creating a pattern for whitespaces
        Pattern patt = Pattern.compile("[\\s]");
  
        // Searching patt in s.
        Matcher mat = patt.matcher(s);
  
        // Replacing
        return mat.replaceAll("");
   }
  
    public static void main(String[] argv)
    {
        String s = "Hello  Everyone  .  Welcome  " + 
                   "to Geeks for Geeks.";
        System.out.println(removeWhite(s));
    }
}

Output:

HelloEveryone.WelcometoGeeksforGeeks.

Attention reader! Don’t stop learning now. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer Complete Interview Preparation Course.

My Personal Notes

Related Articles