GlazedListsDataProvider<Datum> bodyDataProvider = new GlazedListsDataProvider<Datum>(
treeList, columnPropertyAccessor);
final DataLayer bodyDataLayer = new DataLayer(bodyDataProvider);
// Handle update of CheckBoxField objects in column 0
bodyDataLayer.registerCommandHandler(new UpdateDataCommandHandler(
bodyDataLayer) {
@Override
protected boolean doCommand(UpdateDataCommand command) {
int columnPosition = command.getColumnPosition();
int rowPosition = command.getRowPosition();