@Override
  public void emergencyClose() {
    shuttingDown = true;
    queueConnections.getPrimary().emergencyClose();
    List<Connection> backups = queueConnections.getBackups();
    for (Connection backup : backups) {
      backup.emergencyClose();
    }
  }
Manages Client Queues. Responsible for creating callback connections and satisfying redundancy
requirements.

@since GemFire 5.7
geode-core/src/main/java/org/apache/geode/cache/client/internal/QueueManagerImpl.java