JAVAFX Problem trying to play sound when clicking button - javafx

Question

I'm trying to make a sound of Windows play when the user clicks the button. The code is just below:
public class TestController extends Application {
public String audio = getClass().getResource("src/Sounds/WindowsError.wav").toString();
#FXML
private Button playbt;
#FXML
void playtest(MouseEvent event)
{
System.out.println("Clicked!");
AudioClip clip = new AudioClip(audio);// 1
clip.play(); // 2
}
#Override
public void start(Stage primaryStage) {
try
{
FXMLLoader loader = new FXMLLoader(this.getClass().getResource("/FXML/Test.fxml"));
Parent root = loader.load();
Scene scene = new Scene(root);
primaryStage.setTitle("Test");
primaryStage.setScene(scene);
primaryStage.setResizable(false);
primaryStage.show();
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
}
The controller is properly configured to FXML. However, when I try to run the project, the following error occurs.
Exception in Application constructor 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$FXHelper.main(Unknown Source)
Caused by: java.lang.RuntimeException: Unable to construct Application instance: class Controller.TestController
at com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:907)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$159(LauncherImpl.java:182)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$165(LauncherImpl.java:819)
at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$179(PlatformImpl.java:326)
at com.sun.javafx.application.PlatformImpl.lambda$null$177(PlatformImpl.java:295)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$178(PlatformImpl.java:294)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$152(WinApplication.java:177)
... 1 more
Caused by: java.lang.NullPointerException
at Controller.TestController.<init>(TestController.java:17)
... 13 more Exception running application Controller.TestController
The files in my project are arranged as follows:
Does anyone know why this error occurs? The project hangs when opening due to the sound playback code.

Answer 1

I'm not totally solid on this, but I think the syntax of the getResource for the audio variable is in "relative address" form since it doesn't start with "/". In other words, it could be looking for a subfolder src in Controller package folder.
Maybe the following will help the system locate your audio resource:
public String audio = getClass().getResource("../Sounds/WindowsError.wav").toString();
Perhaps it would be good to move this line into the start() method, and run a System.out.println(audio) to inspect what you have at that point.
EDIT: just saw fabian's comment. Changing to the form using the classpath root as he suggests might be a better general practice than my suggestion to use a relative path.