// reset activities and compute model name
String modelName = "";
activities.clear();
if (umlResource != null) {
try {
ModelDecorator modelDec = umlResource.getFirstModelDecorator();
modelName = modelDec.getDecoratedElement().getName();
activityQualifiedNamesViewer.setInput(modelDec);
} catch (ResourceException e) {
updateStatus("Unable to retrieve model decorator : " + e.getMessage());
return;
}