this.signet = signet; this.subject = subject; this.subjectKey = new SubjectKey(subject);
this.subjectKey = new SubjectKey();
  PrivilegedSubjectImpl(Signet signet, Subject subject)  {    this.signet = signet;    this.subject = subject;    this.subjectKey = new SubjectKey(subject);    this.assignmentsReceived = new HashSet();    this.assignmentsGranted = new HashSet();  }