Delete All Whitespaces from a String in Java

To delete all whitespaces from a string, use the replaceAll() method and replace every whitespace with empty.

Let’s say the following is our string.

String str = "This is it!";

Now, let us replace the whitespaces that will eventually delete them.

String res = str.replaceAll("\s+","");

Example

 Live Demo

public class Demo {
   public static void main(String []args) {
      String str = "This is it!";
      System.out.println("String: "+str);
      String res = str.replaceAll("\s+","");
      System.out.println("String after deleting whitespace: "+res);
   }
}

Output

String: This is it!
String after deleting whitespace: Thisisit!