@After
 public void releaseCommunity() {
   _subject.crash();
   _subject = null;
   _a = null;
   _b = null;
 }
  protected SovereignParty newSession(SovereignParty party) {
    SovereignParty restarted = _subject.newSession(party);

    if (party == _a) _a = restarted;
    if (party == _b) _b = restarted;

    return restarted;
  }
 protected void connect(SovereignParty a, SovereignParty b) {
   _subject.connect(a, b);
 }
 protected SovereignParty createParty(String name) {
   return _subject.createParty(name);
 }