JavaFX Line create axis

import javafx.application.Application;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.layout.Pane;
import javafx.scene.shape.Line;
import javafx.scene.shape.Polyline;
import javafx.scene.text.Font;
import javafx.scene.text.Text;
import javafx.stage.Stage;

public class Main extends Application {

   private static double WIDTH = 400;
   private static double HEIGHT = 250;
   private static double CENTER = WIDTH / 2;

   @Override//from  ww w. java  2  s . co  m
   public void start(Stage primaryStage) throws Exception {
      Pane pane = new Pane();

      Polyline xAxis = new Polyline();
      drawXAxis(pane, xAxis);
      Polyline yAxis = new Polyline();
      drawYAxis(pane, yAxis);

      Polyline polyline = new Polyline();
      ObservableList<Double> list = polyline.getPoints();

      for (int x = -100; x <= 100; x++) {
         list.add(x + CENTER);
         double scaleFactor = 0.0125;
         list.add(CENTER - scaleFactor * x * x);
      }
      pane.getChildren().addAll(xAxis, yAxis, polyline);
      primaryStage.setScene(new Scene(pane, WIDTH, HEIGHT));
      primaryStage.setTitle("f(x) = x^2");
      primaryStage.show();

   }

   private static void drawXAxis(Pane pane, Polyline xAxis) {
      ObservableList<Double> xAxisList = xAxis.getPoints();
      double limit = WIDTH * 0.9;

      for (double x = 0; x < limit; x++) {
         xAxisList.add(x);
         xAxisList.add(CENTER);
      }
      Line line1 = new Line(limit, CENTER, limit - WIDTH * 0.05, CENTER * 0.875);
      Line line2 = new Line(limit, CENTER, limit - WIDTH * 0.05, CENTER / 0.875);
      Text text = new Text(limit + (WIDTH * 0.02), CENTER, "X");
      text.setFont(Font.font(22));
      pane.getChildren().addAll(line1, line2, text);
   }

   private static void drawYAxis(Pane pane, Polyline yAxis) {

      ObservableList<Double> yAxisList = yAxis.getPoints();
      double limit = HEIGHT * 0.9;

      for (double y = 0; y < limit; y++) {
         yAxisList.add(CENTER);
         yAxisList.add(y + HEIGHT * 0.1);
      }
      Line line1 = new Line(CENTER, HEIGHT * 0.1, CENTER - WIDTH * 0.05, HEIGHT * 0.2);
      Line line2 = new Line(CENTER, HEIGHT * 0.1, CENTER + WIDTH * 0.05, HEIGHT * 0.2);
      Text text = new Text(limit + (WIDTH * 0.02), HEIGHT * 0.1, "Y");
      text.setFont(Font.font(22));
      pane.getChildren().addAll(line1, line2, text);
   }

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