Java puzzle: protected method no construtor

public DefaultRepresentationResult(...List<Serialization> serializations) {//construtor
    //...
    this.serializations = serializations;
    sortSerializations();
}
 /**
   * Override this method if you want another ordering strategy.
   *
   * @since 3.4.0
   */
protected void sortSerializations() {
       Collections.sort(this.serializations, new PackageComparator());
}

public class Mae {
    public Mae() {
         metodo();
    }
    protected void metodo() {
        System.out.println("Mãe");
    }
}

public class Filha extends Mae {
   private final String x;
   public Filha() {
        this.x = "Testando";
   }
   @Override
   protected void metodo() {
       System.out.println(x);
   }
}

new Filha();