@Override
    public void setSelected(final T item,
                            final boolean selected,
                            final SelectionType selectionType,
                            final boolean fireEvents) {
        if (item != null) {
            final boolean currentlySelected = isSelected(item);
            selection.setSelected(item, selected);
            if (currentlySelected != selected) {
                changes.add(item);
                fireSelectionChangeEvent();
                if (fireEvents) {
                    fireChange(selectionType);
                }
            }
        }
    }
Sets the selected state of the specified item.
stroom-core-client-widget/src/main/java/stroom/widget/util/client/MultiSelectionModelImpl.java