Eclipse Compile Error on Javafx This is my code :

package JavaFX;

import javafx.application.Application;

import javafx.stage.Stage;

import javafx.scene.Node;

import javafx.scene.Scene;

import javafx.scene.paint.Color;

import javafx.scene.text.Font;

import javafx.scene.layout.GridPane;

import javafx.scene.control.Label;

import javafx.scene.control.TextField;

import javafx.scene.control.TextInputControl;

import javafx.scene.control.Button;

import javafx.geometry.Insets;

import javafx.geometry.Pos;

import javafx.geometry.HPos;

import javafx.geometry.VPos;

@SuppressWarnings("restriction")

public class CourseScore extends Application {

private static final Node btnCalculate = null;

private static final Node btnStartAgin = null;

private Label lblEarned = new Label ("Earned Score");

private Label lblMax = new Label ("Max Possible");

private Label lblScore01 = new Label ("Score 1: ");

private Label lblScore02 = new Label ("Score 2: ");

private Label lblScore03 = new Label ("Score 3: ");

private Label lblScore04 = new Label ("Score 4: ");

private Label lblScore05 = new Label ("Score 5: ");

private Label lblScore06 = new Label ("Score 6: ");

private Label lblTotal = new Label ("TOTAL: ");

private Label lblFinalEarned = new Label ("FINAL SCORE: ");

private Label lblFinalGrade = new Label ("FINAL GRADE: ");

private Label lblPerfect = new Label ("Perfect Score!");

private TextField txtEarned01 = new TextField(); private TextField txtMax01 = new TextField();

private TextField txtEarned02 = new TextField(); private TextField txtMax02 = new TextField();

private TextField txtEarned03 = new TextField(); private TextField txtMax03 = new TextField();

private TextField txtEarned04 = new TextField(); private TextField txtMax04 = new TextField();

private TextField txtEarned05 = new TextField(); private TextField txtMax05 = new TextField();

private TextField txtEarned06 = new TextField(); private TextField txtMax06 = new TextField();

private TextField txtTotalEarned = new TextField(); private TextField txtTotalMax = new TextField();

private TextField txtFinalEarned = new TextField(); private TextField txtFinalGarde = new TextField();

private Button btnClaculate = new Button("Calculate");

private Button btnStartAgagin = new Button ("Start Over");

private TextInputControl txtFinalGrade;

private Node btnStartAgain;

@Override

public void start(Stage primaryStage) {

GridPane gridP = new GridPane();

gridP.setAlignment(Pos.CENTER);

gridP.setPadding(new Insets(10, 12, 10, 12));

gridP.setHgap(14);

gridP.setVgap(16);

gridP.setStyle("-fx-background-color: HoneyDew;");

GridPane.setHalignment(lblEarned, HPos.CENTER);

GridPane.setHalignment(lblMax, HPos.CENTER);

GridPane.setHalignment(btnCalculate, HPos.RIGHT);

GridPane.setHalignment(btnStartAgin, HPos.RIGHT);

GridPane.setHalignment(lblScore01, HPos.RIGHT);

GridPane.setHalignment(lblScore02, HPos.RIGHT);

GridPane.setHalignment(lblScore03, HPos.RIGHT);

GridPane.setHalignment(lblScore04, HPos.RIGHT);

GridPane.setHalignment(lblScore05, HPos.RIGHT);

GridPane.setHalignment(lblScore06, HPos.RIGHT);

GridPane.setHalignment(lblTotal, HPos.RIGHT);

GridPane.setHalignment(lblFinalEarned, HPos.RIGHT);

GridPane.setHalignment(lblFinalGrade, HPos.RIGHT);

GridPane.setHalignment(lblPerfect, HPos.CENTER);

GridPane.setValignment(lblPerfect, VPos.TOP);

txtTotalEarned.setEditable(false); txtTotalMax.setEditable(false);

txtFinalEarned.setEditable(false); txtFinalGrade.setEditable(false);

lblTotal.setVisible(true); txtTotalEarned.setVisible(true); txtTotalMax.setVisible(true);

lblFinalEarned.setVisible(true); txtFinalEarned.setVisible(true);

lblFinalGrade.setVisible(true); txtFinalGrade.setVisible(true);

lblPerfect.setVisible(true);

lblEarned.setStyle("-fx-font-size: 15pt;");

lblMax.setStyle("-fx-font-size: 15pt;");

lblPerfect.setTextFill(Color.web("FireBrick"));

lblPerfect.setFont(Font.font("Cambria", 24));

txtFinalEarned.setStyle("-fx-background-color: #E8E8E8");

txtFinalGrade.setStyle("-fx-background-color: #E8E8E8");

txtTotalEarned.setStyle("-fx-background-color: #E8E8E8");

txtTotalMax.setStyle("-fx-background-color: #E8E8E8");

btnCalculate.setStyle("-fx-background-color: FireBrick: -fx-font-size: 12.5pt; -fx-text-fill: White; -fx-font-family: Papyrus;");

gridP.add(lblScore01, 0, 1); gridP.add(lblEarned, 1, 0); gridP.add(lblMax, 2, 0);

gridP.add(lblScore02, 0, 2); gridP.add(txtEarned01, 1, 1); gridP.add(txtMax01, 2, 1);

gridP.add(lblScore03, 0, 3); gridP.add(txtEarned02, 1, 2); gridP.add(txtMax02, 2, 2);

gridP.add(lblScore04, 0, 4); gridP.add(txtEarned03, 1, 3); gridP.add(txtMax03, 2, 3);

gridP.add(lblScore05, 0, 5); gridP.add(txtEarned04, 1, 4); gridP.add(txtMax04, 2, 4);

gridP.add(lblScore06, 0, 6); gridP.add(txtEarned05, 1, 5); gridP.add(txtMax05, 2, 5);

gridP.add(txtEarned06, 1, 6); gridP.add(txtMax06, 2, 6);

gridP.add(lblTotal, 0, 8); gridP.add(txtTotalEarned, 1, 8); gridP.add(txtTotalMax, 2, 8);

gridP.add(lblFinalEarned, 0, 9); gridP.add(txtFinalEarned, 1, 9); gridP.add(btnCalculate, 2, 11);

gridP.add(lblFinalEarned, 0, 10); gridP.add(txtFinalGrade, 1, 10); gridP.add(btnStartAgain, 2, 12);

gridP.add(lblPerfect, 1, 11);

Scene Scene2 = new Scene(gridP);

primaryStage.setScene(Scene2);

primaryStage.setTitle("Calculate Course Score");

primaryStage.setResizable(false);

primaryStage.show();

}

public static void main(String[] args) {

Application.launch(args);

}

}

-----This is the error im getting.

Exception in Application start method

java.lang.reflect.InvocationTargetException

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.lang.reflect.Method.invoke(Unknown Source)

at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:389)

at com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:328)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)

at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

at java.lang.reflect.Method.invoke(Unknown Source)

at sun.launcher.LauncherHelper$FXHelper.main(Unknown Source)

Caused by: java.lang.RuntimeException: Exception in Application start method

at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:917)

at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$154(LauncherImpl.java:182)

at java.lang.Thread.run(Unknown Source)

Caused by: java.lang.NullPointerException

at javafx.scene.layout.Pane.setConstraint(Pane.java:103)

at javafx.scene.layout.GridPane.setHalignment(GridPane.java:424)

at JavaFX.CourseScore.start(CourseScore.java:62)

at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$161(LauncherImpl.java:863)

at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$174(PlatformImpl.java:326)

at com.sun.javafx.application.PlatformImpl.lambda$null$172(PlatformImpl.java:295)

at java.security.AccessController.doPrivileged(Native Method)

at com.sun.javafx.application.PlatformImpl.lambda$runLater$173(PlatformImpl.java:294)

at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)

at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)

at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)

... 1 more

Exception running application JavaFX.CourseScore