JavaFX ObservableList handle change event

import javafx.collections.FXCollections;
import javafx.collections.ListChangeListener;
import javafx.collections.ObservableList;

public class Main {
  public static void main(String[] args) {
    // Create an observable list with two elements 
    ObservableList<String> list = FXCollections.observableArrayList("One", "Two");
    System.out.println(list);/*from w  w  w  . j  ava  2  s .com*/

    list.addListener((ListChangeListener.Change<? extends String> change) -> {
      System.out.println("The map has changed.");
    });

  }
}

import javafx.collections.FXCollections;
import javafx.collections.ListChangeListener;
import javafx.collections.ObservableList;

public class Main {
  public static void main(String[] args) {
    // Create a list with some elements
    ObservableList<String> list = FXCollections.observableArrayList("one", "two");

    System.out.println("After creating the list: " + list);

    // Add a ChangeListener to the list
    list.addListener(Main::onChanged);/* www. j  ava 2  s .  c om*/

    // Add some more elements to the list
    list.addAll("three", "four");
    System.out.println("After addAll() - list: " + list);

    // We have four elements. Remove the middle two from index 1 (inclusive)
    // to index 3 (exclusive)
    list.remove(1, 3);
    System.out.println("After remove() - list: " + list);

    // Retain only the element "one"
    list.retainAll("one");
    System.out.println("After retainAll() - list: " + list);

    // Replace the first element in the list
    list.set(0, "ONE");
    System.out.println("After set() - list: " + list);
  }

  public static void onChanged(ListChangeListener.Change<? extends String> change) {
    while (change.next()) {
      if (change.wasPermutated()) {
        System.out.println("A permutation is detected.");
      } else if (change.wasUpdated()) {
        System.out.println("An update is detected.");
      } else if (change.wasReplaced()) {
        System.out.println("A replacement is detected.");
      } else {
        if (change.wasRemoved()) {
          System.out.println("A removal is detected.");
        } else if (change.wasAdded()) {
          System.out.println("An addition is detected.");
        }
      }
    }
  }
}