Cleanup entries: uncaught exception

[mlep]

JabRef 5.0-beta.532--2020-03-04--8111707
Linux 4.9.0-12-amd64 amd64
Java 13.0.2

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

When adding a "saving action", an uncaught exception occurs.

Steps to reproduce the behavior:

1. Open "Content > Library properties"
2. Check the box "Enable save actions"
3. In the lower-left drop-down list, select a field, such as "Abstract".
4. To the right, click on "Add".

--> A window entitled "Exception Details" is displayed.
"Uncaught exception occurred in Thread[JavaFX Application Thread,5,main]"

The exception stacktrace was

java.lang.NullPointerException
  at org.jabref/org.jabref.gui.cleanup.FieldFormatterCleanupsPanel.lambda$buildLayout$0(Unknown Source)
  at org.jabref/org.jabref.gui.util.ViewModelListCellFactory$1.updateItem(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.ListCell.updateItem(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.ListCell.indexChanged(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.IndexedCell.updateIndex(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.skin.VirtualFlow.setCellIndex(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.skin.VirtualFlow.addTrailingCells(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.skin.VirtualFlow.layoutChildren(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Parent.layout(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Scene.doLayoutPass(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Scene$ScenePulseListener.pulse(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.Toolkit.lambda$runPulse$2(Unknown Source)
  at java.base/java.security.AccessController.doPrivileged(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.Toolkit.runPulse(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.Toolkit.firePulse(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.pulse(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.pulse(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.pulseFromQueue(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.lambda$runToolkit$11(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.gtk.GtkApplication.enterNestedEventLoopImpl(Native Method)
  at org.jabref.merged.module/com.sun.glass.ui.gtk.GtkApplication._enterNestedEventLoop(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.Application.enterNestedEventLoop(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.EventLoop.enter(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.enterNestedEventLoop(Unknown Source)
  at org.jabref.merged.module/javafx.stage.Stage.showAndWait(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.HeavyweightDialog.showAndWait(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.Dialog.showAndWait(Unknown Source)
  at org.jabref/org.jabref.gui.JabRefDialogService.showErrorDialogAndWait(Unknown Source)
  at org.jabref/org.jabref.FallbackExceptionHandler.lambda$uncaughtException$0(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.application.PlatformImpl.lambda$runLater$10(Unknown Source)
  at java.base/java.security.AccessController.doPrivileged(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.application.PlatformImpl.lambda$runLater$11(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.gtk.GtkApplication.enterNestedEventLoopImpl(Native Method)
  at org.jabref.merged.module/com.sun.glass.ui.gtk.GtkApplication._enterNestedEventLoop(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.Application.enterNestedEventLoop(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.EventLoop.enter(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.enterNestedEventLoop(Unknown Source)
  at org.jabref.merged.module/javafx.stage.Stage.showAndWait(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.HeavyweightDialog.showAndWait(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.Dialog.showAndWait(Unknown Source)
  at org.jabref/org.jabref.gui.libraryproperties.LibraryPropertiesAction.execute(Unknown Source)
  at org.jabref/org.jabref.gui.actions.JabRefAction.lambda$new$2(Unknown Source)
  at org.jabref.merged.module/org.controlsfx.control.action.Action.handle(Unknown Source)
  at org.jabref.merged.module/org.controlsfx.control.action.Action.handle(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
  at org.jabref.merged.module/javafx.event.Event.fireEvent(Unknown Source)
  at org.jabref.merged.module/javafx.scene.control.MenuItem.fire(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.scene.control.ContextMenuContent$MenuItemContainer.doSelect(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.scene.control.ContextMenuContent$MenuItemContainer.lambda$createChildren$12(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
  at org.jabref.merged.module/javafx.event.Event.fireEvent(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Scene$MouseHandler.process(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Scene.processMouseEvent(Unknown Source)
  at org.jabref.merged.module/javafx.scene.Scene$ScenePeerListener.mouseEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(Unknown Source)
  at java.base/java.security.AccessController.doPrivileged(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$2(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(Unknown Source)
  at org.jabref.merged.module/com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.View.handleMouseEvent(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.View.notifyMouse(Unknown Source)
  at org.jabref.merged.module/com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
  at org.jabref.merged.module/com.sun.glass.ui.gtk.GtkApplication.lambda$runLoop$11(Unknown Source)
  at java.base/java.lang.Thread.run(Unknown Source)

[Siedlerchr]

Happpens if you add a save actions without selecting a formatter.
I created a fix in #6072 Not sure if it will be still in 5.0 or later.