Bug 18071 Package Viewer: Too many refreshes
F1 - when a working copy is closed, it's package is updated - update on a package results in a refresh as the abstract filter claims that IMAGE is a filter property
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/JavaElementContentProvider.java
});
	}
	
	private void postAdd(final Object parent, final Object element) {
		postRunnable(new Runnable() {
			public void run() {
				
				Control ctrl= fViewer.getControl();
				if (ctrl != null && !ctrl.isDisposed()) 
					fViewer.add(parent, element);
			}
		});
	}
	private void postRemove(final Object element) {
		postRunnable(new Runnable() {
			public void run() {
				
				Control ctrl= fViewer.getControl();
				if (ctrl != null && !ctrl.isDisposed()) 
					fViewer.remove(element);
			}
		});
	}
	private void postRunnable(final Runnable r) {
		Control ctrl= fViewer.getControl();
		if (ctrl != null && !ctrl.isDisposed()) {
			ctrl.getDisplay().asyncExec(r); 
		}
	}
}