import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.scene.Scene;
import javafx.scene.control.TextArea;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class TextAreaTripleClick extends Application{

    private void init(Stage primaryStage) {
        VBox root = new VBox();
        Scene scene = new Scene(root, 400, 200);

        primaryStage.setScene(scene);
        TextArea textarea = new TextArea("the first line\nthe second line\nthe third line");

        root.getChildren().addAll(textarea);
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        init(primaryStage);
        primaryStage.setTitle("TextArea Triple Click Test " + System.getProperty("javafx.runtime.version"));
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}