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
* Returns whether the node corresponding to the given element or tree path is expanded
     * or collapsed.
     * 
     * @param elementOrTreePath
     *           the element
     * @return <code>true</code> if the node is expanded, and <code>false</code>
     *         if collapsed
     */
    public boolean getExpandedState(Object elementOrTreePath) {
        Assert.isNotNull(elementOrTreePath);
        Widget item = internalGetWidgetToSelect(elementOrTreePath);
        if (item instanceof Item)
            return getExpanded((Item) item);
        return false;
    }
    /**
     * Returns the number of child items of the given SWT control.
     * 
     * @param control
     *           the control
     * @return the number of children
     */
    protected abstract int getItemCount(Control control);
    /**
     * Returns the number of child items of the given SWT item.
     * 
     * @param item
     *           the item
     * @return the number of children
     */