var TransactionManager = Java.type("com.change_vision.jude.api.inf.editor.TransactionManager");

var de = astah.getDiagramEditorFactory().getSequenceDiagramEditor();
TransactionManager.beginTransaction();
var diagram = de.createSequenceDiagram(astah.getProject(), "SequenceDiagram");
var lifelineA = de.createLifeline("aaa", 10.0);
var lifelineB = de.createLifeline("bbb", 210.0);
var message = de.createMessage("message", lifelineA, lifelineB, 100.0);
message.getModel().setAsynchronous(true);
TransactionManager.endTransaction();