class InstanceManager {

	public void shutdown() {
		synchronized (this.lock) {
			if (this.isShutdown) {
				return;
			}
			this.isShutdown = true;

			for (Instance i : this.registeredHostsById.values()) {
				i.markDead();
			}

			this.registeredHostsById.clear();
			this.registeredHostsByConnection.clear();
			this.deadHosts.clear();
			this.totalNumberOfAliveTaskSlots = 0;
		}
	}

	public  InstanceManager();

}