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
* 
	 * @see org.eclipse.ui.part.ViewPart#saveState(org.eclipse.ui.IMemento)
	 */
	public void saveState(IMemento memento) {
		super.saveState(memento);
		memento.putString(TAG_GENERATOR, builder.generator.getId());
		builder.saveState(memento);
	}
	/**
	 * Select all of the elements in the receiver.
	 */
	void selectAll() {
		viewer.getTree().selectAll();
	}
	/**
	 * Set the category group for the receiver.
	 * 
	 * @param group
	 */
	void setCategoryGroup(MarkerGroup group) {
		categoriesToExpand.clear();
		builder.setCategoryGroup(group);
	}
	/**
	 * Set the content generator for the receiver.
	 * 
	 * @param generator
	 */
	void setContentGenerator(MarkerContentGenerator generator) {
		viewer.setSelection(new StructuredSelection());