RSSOwl starts with an error

[Sebastian Krysmanski]

Hi there,

since some time RSSOwl can't correctly start anymore. (I think this is/was
related to a crash of my notebook.) Since then I'm just getting a error
messages when I launch RSSOwl:

An error has occurred. See error log for more details.

com.db4o.config.Entry cannot be cast to org.rssowl.core.persist.IFolderChild

The error log contains this stack trace for the error:

java.lang.ClassCastException: com.db4o.config.Entry cannot be cast to org.rssowl.core.persist.IFolderChild
    at org.rssowl.ui.internal.views.explorer.BookMarkLabelProvider.getNewsCount(BookMarkLabelProvider.java:361)
    at org.rssowl.ui.internal.views.explorer.BookMarkLabelProvider.update(BookMarkLabelProvider.java:167)
    at org.eclipse.jface.viewers.ViewerColumn.refresh(ViewerColumn.java:145)
    at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:932)
    at org.eclipse.jface.viewers.AbstractTreeViewer$UpdateItemSafeRunnable.run(AbstractTreeViewer.java:102)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:37)
    at org.eclipse.core.runtime.Platform.run(Platform.java:880)
    at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:48)
    at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
    at org.eclipse.jface.viewers.AbstractTreeViewer.doUpdateItem(AbstractTreeViewer.java:1012)
    at org.eclipse.jface.viewers.StructuredViewer$UpdateItemSafeRunnable.run(StructuredViewer.java:466)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:37)
    at org.eclipse.core.runtime.Platform.run(Platform.java:880)
    at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:48)
    at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175)
    at org.eclipse.jface.viewers.StructuredViewer.updateItem(StructuredViewer.java:2041)
    at org.eclipse.jface.viewers.AbstractTreeViewer.createTreeItem(AbstractTreeViewer.java:827)
    at org.eclipse.jface.viewers.AbstractTreeViewer$1.run(AbstractTreeViewer.java:802)
    at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
    at org.eclipse.jface.viewers.AbstractTreeViewer.createChildren(AbstractTreeViewer.java:776)
    at org.eclipse.jface.viewers.TreeViewer.createChildren(TreeViewer.java:634)
    at org.rssowl.ui.internal.views.explorer.BookMarkViewer.createChildren(BookMarkViewer.java:73)
    at org.eclipse.jface.viewers.AbstractTreeViewer.internalInitializeTree(AbstractTreeViewer.java:1490)
    at org.eclipse.jface.viewers.TreeViewer.internalInitializeTree(TreeViewer.java:823)
    at org.eclipse.jface.viewers.AbstractTreeViewer$5.run(AbstractTreeViewer.java:1474)
    at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1365)
    at org.eclipse.jface.viewers.TreeViewer.preservingSelection(TreeViewer.java:397)
    at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1328)
    at org.eclipse.jface.viewers.AbstractTreeViewer.inputChanged(AbstractTreeViewer.java:1467)
    at org.eclipse.jface.viewers.ContentViewer.setInput(ContentViewer.java:274)
    at org.eclipse.jface.viewers.StructuredViewer.setInput(StructuredViewer.java:1603)
    at org.rssowl.ui.internal.views.explorer.BookMarkExplorer.createViewer(BookMarkExplorer.java:340)
    at org.rssowl.ui.internal.views.explorer.BookMarkExplorer.createPartControl(BookMarkExplorer.java:258)
    at org.eclipse.ui.internal.ViewReference.createPartHelper(ViewReference.java:371)
    at org.eclipse.ui.internal.ViewReference.createPart(ViewReference.java:230)
    at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:594)
    at org.eclipse.ui.internal.WorkbenchPage$ActivationList.setActive(WorkbenchPage.java:4169)
    at org.eclipse.ui.internal.WorkbenchPage$17.runWithException(WorkbenchPage.java:3234)
    at org.eclipse.ui.internal.StartupThreading$StartupRunnable.run(StartupThreading.java:31)
    at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:133)
    at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3800)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3425)
    at org.eclipse.ui.application.WorkbenchAdvisor.openWindows(WorkbenchAdvisor.java:803)
    at org.eclipse.ui.internal.Workbench$27.runWithException(Workbench.java:1363)
    at org.eclipse.ui.internal.StartupThreading$StartupRunnable.run(StartupThreading.java:31)
    at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:133)
    at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3800)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3425)
    at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2295)
    at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2200)
    at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:495)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:490)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
    at org.rssowl.ui.internal.Application.start(Application.java:113)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:386)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
    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 org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1236)

And the "Feeds" sidebar there is an error message that reads:

Could not create the view: An unexpected exception was thrown.

The details contain this stacktrace (I shortened it a little bit):

java.lang.NullPointerException
    at org.eclipse.jface.viewers.ViewerComparator.compare(ViewerComparator.java:138)
    at org.rssowl.ui.internal.views.explorer.BookMarkSorter.compare(BookMarkSorter.java:97)
    at org.eclipse.jface.viewers.ViewerComparator$1.compare(ViewerComparator.java:187)
    at java.util.Arrays.mergeSort(Unknown Source)
    at java.util.Arrays.mergeSort(Unknown Source)
    at java.util.Arrays.mergeSort(Unknown Source)
    at java.util.Arrays.sort(Unknown Source)
    at org.eclipse.jface.viewers.ViewerComparator.sort(ViewerComparator.java:185)
    at org.eclipse.jface.viewers.AbstractTreeViewer.getSortedChildren(AbstractTreeViewer.java:625)
    at org.eclipse.jface.viewers.AbstractTreeViewer$1.run(AbstractTreeViewer.java:799)
       ...
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1236)

My feeds are still there (in the "Feeds" menu) and some of them I can open
(and view) while others I can't.

Can anybody help me with this problem?

Regards

Sebastian

[Sebastian Krysmanski]

Moreover I just tried to export all feeds which didn't work either. There's no
error message. If I click on "Finish" in the Export dialog, I get a "Save to"
dialog, then I select a filename, hit "OK" and get back to the export dialog
without anything happening.

[Anonymous]

Did this happen with RSSOwl 2.0.2? Please follow
http://www.rssowl.org/help#item_6

[Sebastian Krysmanski]

Thank you, man. This exactly solved my problem (altough not until the last
available backup ;). And no: This didn't happen with version 2.0.2 but with
2.0.1.

Regards

Sebastian

[Anonymous]

Ok thanks, its interesting if this ever happens in 2.0.2 because we did some
stability changes for that release.

[Anonymous]

Actually I am wrong, we did this work for 2.0.1. Thats bad, but I guess we are
never totally safe against a crash. But the chance should have become lower
with 2.0.x