public HostStateChange(Host target,URI oldClusterURI){
  this.host=target;
  this.oldInitiators=Sets.newHashSet();
  this.newInitiators=Sets.newHashSet();
  this.oldCluster=oldClusterURI;
}

public HostStateChange ( Host target , URI oldClusterURI ) { this . host = target ; this . oldInitiators = Sets . newHashSet ( ) ; this . newInitiators = Sets . newHashSet ( ) ; this . oldCluster = oldClusterURI ; }
create a new host state
