Bug 28269 type hierarchy makes work much slower even though it's invisible
20021210 i had a big type hierarchy open but put in the background - behind the package explorer i added 1 type to the workspace boom - tyhe whole thing froze for 2 minutes because the type hierarchy was doing a lot of work that i did not ask for and no busy cursor it makes it quite impossible to work if you have a type hierarchy open anywhere
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/typehierarchy/TypeHierarchyViewPart.java
TypeHierarchyViewer superTypesViewer= new SuperTypeHierarchyViewer(fViewerbook, fHierarchyLifeCycle, this);
		initializeTypesViewer(superTypesViewer, keyListener, IContextMenuConstants.TARGET_ID_SUPERTYPES_VIEW);
		
		TypeHierarchyViewer subTypesViewer= new SubTypeHierarchyViewer(fViewerbook, fHierarchyLifeCycle, this);
		initializeTypesViewer(subTypesViewer, keyListener, IContextMenuConstants.TARGET_ID_SUBTYPES_VIEW);
		
		TypeHierarchyViewer vajViewer= new TraditionalHierarchyViewer(fViewerbook, fHierarchyLifeCycle, this);
		initializeTypesViewer(vajViewer, keyListener, IContextMenuConstants.TARGET_ID_HIERARCHY_VIEW);
		fAllViewers= new TypeHierarchyViewer[3];
		fAllViewers[VIEW_ID_SUPER]= superTypesViewer;
		fAllViewers[VIEW_ID_SUB]= subTypesViewer;
		fAllViewers[VIEW_ID_TYPE]= vajViewer;
		
		int currViewerIndex;
		try {
			currViewerIndex= fDialogSettings.getInt(DIALOGSTORE_HIERARCHYVIEW);
			if (currViewerIndex < 0 || currViewerIndex > 2) {
				currViewerIndex= VIEW_ID_TYPE;
			}
		} catch (NumberFormatException e) {
			currViewerIndex= VIEW_ID_TYPE;
		}
			
		fEmptyTypesViewer= new Label(fViewerbook, SWT.LEFT);
		
		for (int i= 0; i < fAllViewers.length; i++) {
			fAllViewers[i].setInput(fAllViewers[i]);
		}