how to find the abs in java code example

Example: abs in java

public class Test { 

   public static void main(String args[]) {
      Integer a = -8;
      double d = -100;
      float f = -90;

      System.out.println(Math.abs(a));
      System.out.println(Math.abs(d));     
      System.out.println(Math.abs(f));    
   }
}