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/AbstractTreeViewer.java
* @param index
     *           if non-negative, indicates the position to insert the item
     *           into its parent
     * @return the newly-created item
     */
    protected abstract Item newItem(Widget parent, int style, int index);
    /**
     * Removes the given elements from this viewer. The selection is updated if
     * required.
     * <p>
     * This method should be called (by the content provider) when elements
     * have been removed from 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 remove
     */
    public void remove(final Object[] elements) {
        assertElementsNotNull(elements);
        if (elements.length == 0) {
        	return;
        }
        preservingSelection(new Runnable() {
            public void run() {
                internalRemove(elements);
            }
        });
    }