Bug 208791 [Markers] NPE in ExtendedMarkersView
org.eclipse.swt.SWTException: Failed to execute runnable (java.lang.NullPointerException) at org.eclipse.swt.SWT.error(SWT.java:3706) at org.eclipse.swt.SWT.error(SWT.java:3624) [... snip ...] Caused by: java.lang.NullPointerException at org.eclipse.ui.internal.provisional.views.markers.ExtendedMarkersView$10.runInUIThread(ExtendedMarkersView.java:896) at org.eclipse.ui.progress.UIJob$1.run(UIJob.java:94) at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35) at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:130) ... 52 more This brought down testResourceMappings(), but you just need to check getCategories() can return null. PW
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/ExtendedMarkersView.java
* @return Object
	 */
	Object getViewerInput() {
		return viewer.getInput();
	}
	/**
	 * Get all of the fields visible in the receiver.
	 * 
	 * @return MarkerField[]
	 */
	MarkerField[] getVisibleFields() {
		return builder.getGenerator().getVisibleFields();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.part.ViewPart#init(org.eclipse.ui.IViewSite,
	 *      org.eclipse.ui.IMemento)
	 */
	public void init(IViewSite site, IMemento memento) throws PartInitException {
		super.init(site, memento);
		MarkerContentGenerator generator = null;
		if (memento != null) {
			generator = MarkerSupportRegistry.getInstance().getGenerator(
					memento.getString(TAG_GENERATOR));
		}
		if (generator == null) {
			String id = site.getId();
			if (id.equals(IPageLayout.ID_BOOKMARKS))
				generator = MarkerSupportRegistry.getInstance().getGenerator(