default void invokeOnColumn(String columnKey, int rowIndex, Consumer<UIColumn> callback) {
        forEachColumn((column) -> {
            if (column.getColumnKey((UIComponent) this, rowIndex).equals(columnKey)) {
                callback.accept(column);
                return false;
            }
            return true;
        });
    }
Return each {@link Row} in a Column Group.
@param context  the {@link FacesContext}
@param cg the {@link ColumnGroup} to get
@param skipUnrendered If unrendered components should be skipped
@param callback The callback, which will be invoked for each row. If it returns false, the algorithm will be cancelled
@return false when the algorithm was cancelled
primefaces/src/main/java/org/primefaces/component/api/ColumnAware.java