Bug 123319 [Markers] ClassCastException during marker update
3.2 20050116 It is possible to get the following ClassCastException during marker updates. This is because the refreshes are not IMarkers and should not be processed. !ENTRY org.eclipse.core.jobs 4 2 2006-01-10 16:00:48.468 !MESSAGE An internal error occurred during: "Process resource updates". !STACK 0 java.lang.ClassCastException at org.eclipse.ui.views.markers.internal.MarkerView$MarkerProcessJob.getExistingMarkers(MarkerView.java:206) at org.eclipse.ui.views.markers.internal.MarkerView$MarkerProcessJob.run(MarkerView.java:169) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:58)
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/MarkerView.java
* with the contents of the message attribute of this marker. In other cases
	 * (more than one marker is selected) the status area indicates how many
	 * items have been selected.
	 * <p>
	 * This method may be overwritten.
	 * </p>
	 * <p>
	 * This method is called whenever a selection changes in this view.
	 * </p>
	 * 
	 * @param selection
	 *            a valid selection or <code>null</code>
	 */
	protected void updateStatusMessage(IStructuredSelection selection) {
		String message = ""; 
		if (selection == null || selection.size() == 0) {
			
			message = updateSummaryVisible();
		} else if (selection.size() == 1) {
			
			Object first = selection.getFirstElement();
			if (first instanceof ConcreteMarker) {
				message = ((ConcreteMarker) first).getDescription();
			}
		} else if (selection.size() > 1) {
			
			message = updateSummarySelected(selection);
		}
		getViewSite().getActionBars().getStatusLineManager()
				.setMessage(message);