public boolean hasSelection() {
    return getSelectedRowCount() > 0;
  }
Returns the tool tip for the specified row. By default always returns {@code null}. Override in
descending classes.

@param diff the current {@code Diff} object to use for rendering the tool tip data
@param row the row to obtain a tooltip for.
@return the tool tip
java/ui/src/main/java/com/google/security/zynamics/bindiff/gui/tabpanels/projecttabpanel/treenodepanels/tables/AbstractTable.java