Hi

I cloned the project and tried to execute the client but the NullPointerException was thrown. I have done a debug and found that the problem was in this class called SceneManager which has a field whose name is sceneMap, so when this piece of code "sceneMap.get(id).getScene()" was called It might have returned null. Because of it is using this api CustomStage, I couldn't do nothing to solve the issue; however, I replaced the lines 23 and 24 in the class StartRentLio to FXMLoader.load(); and the application showed but the button did not work.

here is the entire exception.

Not a directory 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:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:564) at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:464) at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication(LauncherImpl.java:363) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:564) at java.base/sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:1051) Caused by: java.lang.RuntimeException: Exception in Application start method at javafx.graphics/com.sun.javafx.application.LauncherImpl.launchApplication1(LauncherImpl.java:900) at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication$2(LauncherImpl.java:195) at java.base/java.lang.Thread.run(Thread.java:832) Caused by: java.lang.NullPointerException at lk.vivoxalabs.scenemanager.SceneManager.getScene(SceneManager.java:62) at com.chamodshehanka.rentlio.client.start.StartRentLio.start(StartRentLio.java:26) at javafx.graphics/com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$9(LauncherImpl.java:846) at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runAndWait$12(PlatformImpl.java:455) at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(PlatformImpl.java:428) at java.base/java.security.AccessController.doPrivileged(AccessController.java:391) at javafx.graphics/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(PlatformImpl.java:427) at javafx.graphics/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:96) at javafx.graphics/com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method) at javafx.graphics/com.sun.glass.ui.gtk.GtkApplication.lambda$runLoop$11(GtkApplication.java:277) ... 1 more Exception running application com.chamodshehanka.rentlio.client.start.StartRentLio

I tried to run the application on java 11 version and none of the projects were showing any error. I would like to run this application in order to learn the written code. I would like to ask what should I do to get rid of that error because I have tried everything and nothing seem to work. Thank you for sharing this project.

Regards.

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