public class Base64{

    public static int getBase64ByteSize(String str){

      long occurences = str.chars().filter(c -> c =='ä' ).count();

      System.out.println(occurences);
      int n = str.length() + (int)occurences;

      int z = 4 * (int) Math.ceil( (double) n/3);

      return z;
    }



    public static void main(String[] args){

      System.out.println(getBase64ByteSize("Hätte"));
    }
  }