//ITreeModelSource objTreeModelSource = getTreeModelSource();
ITreeStateModel objStateModel = objTreeModelSource.getTreeModel().getTreeStateModel();
boolean bState = objStateModel.isUniqueKeyExpanded(objValueUID);
if (bState) {
objStateModel.collapse(objValueUID);
fireNodeCollapsed(objValueUID, objTreeModelSource);
} else {
objStateModel.expandPath(objValueUID);
fireNodeExpanded(objValueUID, objTreeModelSource);
}