Bug 92344 [call hierarchy] JavaModelException when accessing removed type
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/util/JavaUIHelp.java
}
		public JavaUIHelpListener(JavaEditor editor, String contextId) {
			fContextId= contextId;
			fEditor= editor;
		}
		/*
		 * @see HelpListener#helpRequested(HelpEvent)
		 * 
		 */
		public void helpRequested(HelpEvent e) {
			try {
				Object[] selected= null;
				if (fViewer != null) {
					ISelection selection= fViewer.getSelection();
					if (selection instanceof IStructuredSelection) {
						selected= ((IStructuredSelection)selection).toArray();
					}
				} else if (fEditor != null) {
					IJavaElement input= SelectionConverter.getInput(fEditor);
					if (ActionUtil.isOnBuildPath(input)) {
						selected= SelectionConverter.codeResolve(fEditor);
					}
				}
				JavadocHelpContext.displayHelp(fContextId, selected);
			} catch (CoreException x) {
				JavaPlugin.log(x);
			}
		}
	}
	private static class JavaUIHelpContextProvider implements IContextProvider {