Opening new Window (Stage) and closing it, in JavaFx using the FXML

Fenetre1.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.text.Font?>

<AnchorPane prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1" fx:controller="org.pland.dc.Fenetre1Controller">
   <children>
      <Button fx:id="Button1" layoutX="240.0" layoutY="269.0" mnemonicParsing="false" onAction="#new_window" prefHeight="34.0" prefWidth="102.0" text="Ok" />
      <Label fx:id="label1" alignment="CENTER" layoutX="197.0" layoutY="88.0" prefHeight="36.0" prefWidth="205.0" text="FENETRE 1" textFill="#2172ff">
         <font>
            <Font name="System Bold" size="25.0" />
         </font>
      </Label>
   </children>
</AnchorPane>

Fenetre1Controller.java

import java.io.IOException;

import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Modality;
import javafx.stage.Stage;

public class Fenetre1Controller {
	

	@FXML
	private Button Button1;// déclaration des variables obligatoires sinon elles ne s'affichent pas

	@FXML
	private Label label1;

	@FXML
	private void new_window() {
		try {

			FXMLLoader loader = new FXMLLoader();
			loader.setLocation(Main.class.getResource("Fenetre2.fxml"));
			AnchorPane page = (AnchorPane) loader.load();

			Stage stage = new Stage();
			Scene scene = new Scene(page);
			stage.initModality(Modality.APPLICATION_MODAL);// on ne peut pas écrire dans les autres fenêtres
			
			Fenetre2Controller controller = loader.getController();//Returns the controller associated with the root object.
			controller.setStage(stage);

			stage.setTitle("Fenetre2");
			stage.setScene(scene);
			stage.show();

		} catch (IOException e) {
			e.printStackTrace();

		}
	}

}

Fenetre2.fxml

<?xml version="1.0" encoding="UTF-8"?>

<?import javafx.scene.control.Button?>
<?import javafx.scene.control.Label?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.layout.AnchorPane?>
<?import javafx.scene.layout.ColumnConstraints?>
<?import javafx.scene.layout.GridPane?>
<?import javafx.scene.layout.RowConstraints?>

<AnchorPane prefHeight="358.0" prefWidth="400.0" xmlns="http://javafx.com/javafx/8.0.171" xmlns:fx="http://javafx.com/fxml/1" fx:controller="org.pland.dc.Fenetre2Controller">
   <children>
      <GridPane layoutX="52.0" layoutY="85.0" prefHeight="168.0" prefWidth="257.0">
        <columnConstraints>
          <ColumnConstraints hgrow="SOMETIMES" maxWidth="137.0" minWidth="10.0" prefWidth="82.0" />
          <ColumnConstraints hgrow="SOMETIMES" maxWidth="175.0" minWidth="10.0" prefWidth="175.0" />
        </columnConstraints>
        <rowConstraints>
          <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
          <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
          <RowConstraints minHeight="10.0" prefHeight="30.0" vgrow="SOMETIMES" />
        </rowConstraints>
         <children>
            <Label fx:id="labelnom" alignment="CENTER" maxHeight="1.7976931348623157E308" maxWidth="1.7976931348623157E308" text="Nom" />
            <Label fx:id="labelprenom" alignment="CENTER" maxHeight="1.7976931348623157E308" maxWidth="1.7976931348623157E308" text="Prenom" GridPane.rowIndex="1" />
            <Label fx:id="labelmail" alignment="CENTER" maxHeight="1.7976931348623157E308" maxWidth="1.7976931348623157E308" text="Mail" GridPane.rowIndex="2" />
            <TextField fx:id="textfieldnom" GridPane.columnIndex="1" />
            <TextField fx:id="textfieldprenom" GridPane.columnIndex="1" GridPane.rowIndex="1" />
            <TextField fx:id="textfieldmail" GridPane.columnIndex="1" GridPane.rowIndex="2" />
         </children>
      </GridPane>
      <Button fx:id="butonvalider" layoutX="175.0" layoutY="290.0" mnemonicParsing="false" onAction="#Valider" prefHeight="33.0" prefWidth="82.0" text="Valider" />
   </children>
</AnchorPane>

Fenetre2Controller.java

import javafx.fxml.FXML;

import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;

import javafx.stage.Stage;

public class Fenetre2Controller {

	@FXML
	private Label labelnom;

	@FXML
	private Label labelprenom;

	@FXML
	private Label labelmail;

	@FXML
	private Button butonvalider;

	@FXML
	private TextField textfieldmail;

	@FXML
	private TextField textfieldnom;

	@FXML
	private TextField textfieldprenom;

	private Stage stage;
	
	
	public void setStage(Stage stage) {
        this.stage = stage;
    }
	
	

	@FXML
	private void Valider() {

		stage.close();

	}
}

Main.java

import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.stage.Stage;
import javafx.scene.Parent;
import javafx.scene.Scene;



public class Main extends Application {
	@Override
	public void start(Stage primaryStage) {
		try {
											
			Parent root = FXMLLoader.load(getClass().getResource("Fenetre1.fxml"));
		
			Scene scene = new Scene(root,600,400);
			primaryStage.setTitle("Test Fenetres");
			
			primaryStage.setScene(scene);
			primaryStage.show();
		} catch(Exception e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		launch(args);
	}
}