Bug 84314 [Viewers] Need to allow mapping elements to multiple widgets/items
One of the projects I am working on is using an essentially graph structured dependancy model and we use TableTreeViewer for browsing (drilling down) through this graph. The nature of the model is such that the same model element can occur in multiple positions (paths) of the three. Current implementation of the TreeViewer and TableTreeViewer do not support such one-to-many mapping of model elements to widgets, leading to loads of unnecessary overhead to enshure that correct items will get updated. Suggestion: Element -> Item mapper should allow returning of more than one item per model element that is associated with this element.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TableViewer.java
/**
	 * Initialize the virtual manager to manage the virtual state
	 * if the table is VIRTUAL. If not use the default no-op
	 * version.
	 * @param style
	 */
	private void initializeVirtualManager(int style) {
		if((style & SWT.VIRTUAL) == 0)
			return;
			
		virtualManager = new VirtualManager();	
	}
	/**
	 * Adds the given elements to this table viewer. If this viewer does not
	 * have a sorter, the elements are added at the end in the order given;
	 * otherwise the elements are inserted at appropriate positions.
	 * <p>
	 * This method should be called (by the content provider) when elements have
	 * been added to the model, in order to cause the viewer to accurately
	 * reflect the model. This method only affects the viewer, not the model.
	 * </p>
	 * 
	 * @param elements
	 *            the elements to add
	 */
	public void add(Object[] elements) {
		assertElementsNotNull(elements);
		Object[] filtered = filter(elements);
		
		for (int i = 0; i < filtered.length; i++) {