Bug 111631 [Viewers] TreeViewer needs more TableViewer API
As the TreeViewer is meant to replace the TableTreeViewer we need to add some of the API that the TableViewer had to it so that it can be used like a table. public void insert(Object element, int position) public void add(Object[] objects) Both need to be added.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
}
    }
    /**
     * Removes the given elements from this viewer.
     * <p>
     * EXPERIMENTAL.  Not to be used except by JDT.
     * This method was added to support JDT's explorations
     * into grouping by working sets, which requires viewers to support multiple 
     * equal elements.  See bug 76482 for more details.  This support will
     * likely be removed in Eclipse 3.2 in favour of proper support for
     * multiple equal elements. 
     * </p>
     * 
     * @param elementsOrPaths
     *           the elements or element paths to remove
     * @since 3.1
     */
    protected void internalRemove(Object[] elementsOrPaths) {
        Object input = getInput();
        
        
        CustomHashtable parentItems = new CustomHashtable(5);
        for (int i = 0; i < elementsOrPaths.length; ++i) {
            Object element = elementsOrPaths[i];
			if (equals(element, input)) {
                setInput(null);
                return;
            }
            Widget[] childItems = internalFindItems(element);
			for (int j = 0; j < childItems.length; j++) {