Jabref: NPE when trying to open Option -> Preferences

[Nerator]

• [x] I have tested the latest master version from http://builds.jabref.org/master/ and the problem persists

JabRef 5.0-dev--snapshot--2018-10-17--master--d37ef3e18
Linux 4.15.0-36-generic amd64
Java 1.8.0_181

Steps to reproduce:

1. Open JabRef
2. Click on "Option" menu
3. Click on "Preferences"

Program doesn't freeze, but prints stack trace in console. Option menu doesn't appear. Entry "Uncaught exception occurred in Thread[JavaFX Application Thread,5,main]" appears in event log

Stack trace

[JavaFX Application Thread] ERROR org.jabref.FallbackExceptionHandler - Uncaught exception occurred in Thread[JavaFX Application Thread,5,main] java.lang.NullPointerException: null at org.jabref.gui.preferences.AppearancePrefsTab.<init>(AppearancePrefsTab.java:56) ~[JabRef--master--latest.jar:?] at org.jabref.gui.preferences.PreferencesDialog.<init>(PreferencesDialog.java:91) ~[JabRef--master--latest.jar:?] at org.jabref.gui.actions.ShowPreferencesAction.execute(ShowPreferencesAction.java:15) ~[JabRef--master--latest.jar:?] at org.jabref.gui.actions.JabRefAction.lambda$new$899(JabRefAction.java:29) ~[JabRef--master--latest.jar:?] at org.controlsfx.control.action.Action.handle(Action.java:419) ~[JabRef--master--latest.jar:?] at org.controlsfx.control.action.Action.handle(Action.java:64) ~[JabRef--master--latest.jar:?] at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86) ~[jfxrt.jar:?] at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) ~[jfxrt.jar:?] at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) ~[jfxrt.jar:?] at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) ~[jfxrt.jar:?] at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) ~[jfxrt.jar:?] at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74) ~[jfxrt.jar:?] at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49) ~[jfxrt.jar:?] at javafx.event.Event.fireEvent(Event.java:198) ~[jfxrt.jar:?] at javafx.scene.control.MenuItem.fire(MenuItem.java:462) ~[jfxrt.jar:?] at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer.doSelect(ContextMenuContent.java:1405) ~[jfxrt.jar:?] at com.sun.javafx.scene.control.skin.ContextMenuContent$MenuItemContainer.lambda$createChildren$6(ContextMenuContent.java:1358) ~[jfxrt.jar:?] at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218) ~[jfxrt.jar:?] at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80) ~[jfxrt.jar:?] at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) ~[jfxrt.jar:?] at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) ~[jfxrt.jar:?] at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59) ~[jfxrt.jar:?] at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) ~[jfxrt.jar:?] at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) ~[jfxrt.jar:?] at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) ~[jfxrt.jar:?] at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) ~[jfxrt.jar:?] at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) ~[jfxrt.jar:?] at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) ~[jfxrt.jar:?] at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) ~[jfxrt.jar:?] at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) ~[jfxrt.jar:?] at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74) ~[jfxrt.jar:?] at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54) ~[jfxrt.jar:?] at javafx.event.Event.fireEvent(Event.java:198) ~[jfxrt.jar:?] at javafx.scene.Scene$MouseHandler.process(Scene.java:3757) ~[jfxrt.jar:?] at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485) ~[jfxrt.jar:?] at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762) ~[jfxrt.jar:?] at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494) ~[jfxrt.jar:?] at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:394) ~[jfxrt.jar:?] at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:295) ~[jfxrt.jar:?] at java.security.AccessController.doPrivileged(Native Method) ~[?:1.8.0_181] at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$2(GlassViewEventHandler.java:432) ~[jfxrt.jar:?] at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389) ~[jfxrt.jar:?] at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:431) ~[jfxrt.jar:?] at com.sun.glass.ui.View.handleMouseEvent(View.java:555) ~[jfxrt.jar:?] at com.sun.glass.ui.View.notifyMouse(View.java:937) ~[jfxrt.jar:?] at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method) ~[jfxrt.jar:?] at com.sun.glass.ui.gtk.GtkApplication.lambda$null$5(GtkApplication.java:139) ~[jfxrt.jar:?] at java.lang.Thread.run(Thread.java:748) [?:1.8.0_181]

[Nerator]

same behavior on

JabRef 5.0-dev--snapshot--2018-10-17--master--d37ef3e18
Windows 10 10.0 amd64
Java 1.8.0_181

[Siedlerchr]

Maybe related to the dark theme. I will look into this

[Nerator]

From what I understood, prefs.get(JabRefPreferences.FX_THEME) returns null https://github.com/JabRef/jabref/blob/d37ef3e185b85563d0a68c430b88af3d18833b10/src/main/java/org/jabref/gui/preferences/AppearancePrefsTab.java#L56

I traced it to here: https://github.com/JabRef/jabref/blob/d37ef3e185b85563d0a68c430b88af3d18833b10/src/main/java/org/jabref/preferences/JabRefPreferences.java#L445

Unfortunately I'm not familiar yet with Preferences. But I don't think the FX_THEME is set up anywhere in defaults in the constructor. Hope this may help.

[Ali96kz]

It's my commit. I thought about making Base.css as default, but if dark theme not setted ThemeLoader.java would apply Base.css twice. So I think we should just check it for null in AppearancePrefsTab.java

[Ali96kz]

@Siedlerchr Could I work on that issue?

[Siedlerchr]

@Ali96kz Sure, go ahead.

[tobiasdiez]

Should be fixed now thanks to @Ali96kz.