+ @Override
+ public Set<Variable> perform(ReadGraph graph) throws DatabaseException {
+
+ ITask task = DocumentRequest.PROFILE ? ThreadLogger.task(this) : null;
+
+ StructuralResource2.getInstance(graph);
+ if(variable == null)
+ return Collections.emptySet();
+
+ Collection<Variable> children = graph.syncRequest(new VariableChildren(variable));