This code worked prior to the Java update, thus I'm assuming the problem lies there. I'm referring to the java update what was release on Jan 18th (Java 8 Update 321).
I've tried giving the full path of the .fxml file in .getResource(".."), but that also didn't help.
I've also tried finding the previous version of Java (prior to Java 8 update 321) and trying to install it instead, but I couldn't find it anywhere.
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
public class Conway extends Application {
@Override
public void start(Stage stage) throws Exception{
Parent root = FXMLLoader.load(getClass().getResource("Conway.fxml"));
Scene scene = new Scene(root);
stage.setTitle("John Conway");
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
this part is probably of no importance, but i'll add it just in case:
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
public class ConwayController {
@FXML
private Canvas canvas;
private boolean start = true;
private static int[][] currentColor = new int[10][10];
private static int[][] nextColor = new int[10][10];
/* adds up living neighbors in the array, and returns livingNeighbors */
public static int checkValidNeighbors(int i, int j) {
int livingNeighbors = 0;
/* gets data from neighbors */
for(int k = i - 1; k < i+2; k++) {
if(k >= 0 && k <=9) {
for(int l = j - 1; l < j + 2; l++) {
if(l >= 0 && l <= 9) {
/* not to count himself as a living neighbor */
if((currentColor[k][l] == 1) && !((k == i) && (l == j)))
livingNeighbors += 1;
}
}
}
}
return livingNeighbors;
}
/* decides by the state of the next color by it's current color and the neighbors color */
public static void updateNextColor() {
int livingNeighbors = 0;
// calculate next colors
for(int i = 0; i < 10; i++) {
livingNeighbors = 0;
for(int j = 0; j < 10; j++) {
livingNeighbors = checkValidNeighbors(i, j);
// if dead and surrounded by 3 neighbors -> live next generation
if((currentColor[i][j] == 0) && (livingNeighbors == 3))
nextColor[i][j] = 1;
// if alive
if(currentColor[i][j] == 1) {
// if too little or too many neighbors -> death next generation
if((livingNeighbors <= 1) || (livingNeighbors >= 4))
nextColor[i][j] = 0;
// if 2 or 3 neighbors -> live next generation
if(livingNeighbors == 3 || livingNeighbors == 2)
nextColor[i][j] = 1;
}
}
}
/* puts the next colors into correntColor for the next coloring */
for(int i = 0; i < 10; i++) {
for(int j = 0; j < 10; j++) {
currentColor[i][j] = nextColor[i][j];
}
}
}
@FXML
void NextGenerationButtonPressed(ActionEvent event) {
GraphicsContext gc = canvas.getGraphicsContext2D();
gc.clearRect(0, 0, canvas.getWidth(), canvas.getHeight());
int livingNeighbors = 0, k = 0, l = 0;
/* if it's the first button push, initialize currentColor to random values */
if(start == true) {
start = false;
/* initializes currentColor to random 1s and 0s */
for(int i = 0; i < 10; i++) {
int j = 0;
for(j = 0; j < 10; j++)
currentColor[i][j] = (int)Math.round(Math.random());
}
/* draws the rectangles according to currentColor data */
for(int i = 0; i < canvas.getWidth(); i += canvas.getWidth()/10, k++) {
l = 0;
for(int j = 0; j < canvas.getHeight(); j += canvas.getWidth()/10, l++) {
if(currentColor[k][l] == 1) {
gc.setFill(Color.BLACK);
} else {
gc.setFill(Color.WHITE);
}
gc.fillRect(i, j, canvas.getWidth()/10, canvas.getWidth()/10);
gc.strokeRect(i, j, canvas.getWidth()/10, canvas.getWidth()/10);
}
}
updateNextColor();
}
/* if the currentColor is already initialized */
else {
for(int i = 0; i < canvas.getWidth(); i += canvas.getWidth()/10, k++) {
l = 0;
for(int j = 0; j < canvas.getHeight(); j += canvas.getWidth()/10, l++) {
if(currentColor[k][l] == 1) {
gc.setFill(Color.BLACK);
} else {
gc.setFill(Color.WHITE);
}
gc.fillRect(i, j, canvas.getWidth()/10, canvas.getWidth()/10);
gc.strokeRect(i, j, canvas.getWidth()/10, canvas.getWidth()/10);
}
}
updateNextColor();
}
}
}
The error:
Exception in Application start method
java.lang.reflect.InvocationTargetException
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:465)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:364)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1071)
Caused by: java.lang.RuntimeException: Exception in Application start method
at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:901)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:196)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.NullPointerException: Location is required.
at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3324)
at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3287)
at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3255)
at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3227)
at javafx.fxml/javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:3203)
at javafx.fxml/javafx.fxml.FXMLLoader.load(FXMLLoader.java:3196)
at Conway.start(Conway.java:12)
at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:847)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:484)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:457)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:456)
at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96)
at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:184)
... 1 more
Exception running application Conway
