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/StructuredViewer.java
* the update. For example, if the label provider is not affected by changes
	 * to any of these properties, an update may not actually be required.
	 * Specifing <code>properties</code> as <code>null</code> forces a full
	 * update of the element.
	 * </p>
	 * <p>
	 * If the viewer has a sorter which is affected by a change to one of the
	 * properties, the element's position is updated to maintain the sort order.
	 * </p>
	 * <p>
	 * If the viewer has a filter which is affected by a change to one of the
	 * properties, the element may appear or disappear if the change affects
	 * whether or not the element is filtered out.
	 * </p>
	 * 
	 * @param element
	 *            the element
	 * @param properties
	 *            the properties that have changed, or <code>null</code> to
	 *            indicate unknown
	 */
	public void update(Object element, String[] properties) {
		Assert.isNotNull(element);
		Widget item = findItem(element);
		if (item == null)
			return;
		internalUpdate(item, element, properties);
	}
	/**
     * Updates the given element's presentation when one or more of its