Bug 153993 [Viewers] Common Baseclass for Tree/TableEditorImpl
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TableEditorImpl.java
showSelection();
        columnNumber = column;
        activateCellEditor();
    }
    abstract Rectangle getBounds(Item item, int columnNumber);
/**
     * Return the array of CellEditors used in the viewer
     * @return the cell editors
     */
    public CellEditor[] getCellEditors() {
        return cellEditors;
    }
    /**
     * Get the cell modifier
     * @return the cell modifier
     */
    public ICellModifier getCellModifier() {
        return cellModifier;
    }
    abstract int getColumnCount();
	/**
     * Return the properties for the column
     * @return the array of column properties
     */
    public Object[] getColumnProperties() {
        return columnProperties;
    }
    
    abstract Item[] getSelection();