Run the code:

import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.text.Font;
import javafx.scene.text.Text;
import javafx.stage.Stage;

public class TextAlignment extends Application {

    public static void main(String[] args) {
        launch(args);
    }
    int counter = 0;

    @Override
    public void start(Stage stage) throws Exception {
        final String content = "The quick brown fox jumps over the lazy dog.\nWoven silk pyjamas exchanged for blue quartz?\nHave a pick: twenty six letters - no forcing a jumbled quiz!\n";
        final ObservableList<javafx.scene.text.TextAlignment> alignments = FXCollections.<javafx.scene.text.TextAlignment>observableArrayList(javafx.scene.text.TextAlignment.LEFT, javafx.scene.text.TextAlignment.CENTER, javafx.scene.text.TextAlignment.RIGHT, javafx.scene.text.TextAlignment.JUSTIFY);

        double fontSize = 15.0;
        double space = 10.0;

        final Text Text_b = new Text(space, 3 * space, content);
        Text_b.setFont(new Font(fontSize));
        Text_b.setFill(Color.BLACK);
        Text_b.setWrappingWidth(200);
        Text_b.setTextAlignment(alignments.get(counter));
        Text_b.setFocusTraversable(true);
        Text_b.setOnKeyPressed(new EventHandler<KeyEvent>() {
            @Override
            public void handle(KeyEvent e) {
                if (e.getCode().equals(KeyCode.LEFT)) {
                    if (counter < alignments.size() - 1) {
                        counter++;
                    } else {
                        counter = 0;
                    }
                }

                Text_b.setTextAlignment(alignments.get(counter));
                System.out.println(alignments.get(counter));
            }
        });

        Pane pane = new Pane();
        pane.getChildren().add(Text_b);
        Scene scene = new Scene(pane, 300, 300);
        stage.setScene(scene);
        stage.show();
    }
}

In SW and prism rendering. JUSTIFY alignment is the same as LEFT alignment.